GeolCarp_Vol66_No2_117

www.geologicacarpathica.com

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

, APRIL 2015, 66, 2, 117—132 doi: 10.1515/geoca-2015-0014

Introduction

Within the activity of the Berriasian Working Group (Interna-
tional Subcommission on Cretaceous Stratigraphy – I.S.C.S.),
macrofossil  sampling  in  the  upper  Tithonian  to  lower
Berriasian  interval  has  promoted  the  collection  of  new  am-
monite  faunas  from  southeast  France.  A  first  account  of  the
most  significant  late  Tithonian  Perisphinctoidea  (Ammo-
nitina) from Le Chouet (Drôme, France) highlighted several
taxonomic  and  biostratigraphic  problems  (Bulot  et  al.
2014).  Regarding  the  family  Himalayitidae  Spath,  1925,
the genus Micracanthoceras Spath, 1925 was discussed and
the  new  genera  Ardesciella  and  Pratumidiscus  were  intro-
duced  for  Mediterranean  himalayitids  that  had  previously
been  attributed  to  Corongoceras  Spath,  1925  or  Riasanites
Spath, 1923.

A new biostratigraphic scheme was proposed for the upper

Tithonian of Le Chouet (Wimbledon et al. 2013; Bulot et al.
2014).  A  Moravisphinctes  fischeri  Subzone  was  introduced
for  the  upper  part  of  the  Micracanthoceras  microcanthum
Zone  that  correlates  with  the  uppermost  part  of  the  calpio-
nellid  Tintinopsella  remanei  and  Crassicolaria  intermedia
Subzones  (Crassicollaria  Zone).  In  the  uppermost  upper
Tithonian, a Protacanthodiscus andreaei Zone ( = D. vulgaris
Zone sensu Sarti, 1988) was defined on the first occurrence
of the genus Protacanthodiscus Spath, 1923. This zone coin-
cides  in  calpionellid  terms  with  the  uppermost  part  of  the

Upper Tithonian Himalayitidae Spath, 1925

(Perisphinctoidea, Ammonitina) from Le Chouet

(Drôme, France): implications for the systematics

CAMILLE FRAU

, LUC G. BULOT

and WILLIAM A.P. WIMBLEDON

9bis Chemin des Poissonniers, 13600 La Ciotat, France; camille_frau@hotmail.fr

Aix-Marseille Université, UMR-CNRS 7330 CEREGE, Centre Saint-Charles, case 67, place Victor Hugo 3, 13331 Marseille cedex 03,

France; bulot@cerege.fr

School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, United Kingdom;

mishenka1@yahoo.co.uk

(Manuscript received November 4, 2014; accepted in revised form March 12, 2015)

Abstract: This contribution focuses on the late Tithonian ammonite faunas belonging to the Family Himalayitidae
Spath  in  the  key-section  of  Le  Chouet  (Drôme,  France).  The  great  majority  of  specimens  from  the  Mediterranean
Tethys,  previously  referred  to  Durangites  Burckhardt,  are  now  interpreted  as  juveniles  and/or  microconchs  of  the
highly variable species Protacanthodiscus andreaei (Kilian). Moreover, comparison between specimens from France,
Spain and Bulgaria formerly assigned to Durangites astillerensis Imlay and the type material of this species, supports
the  introduction  of  Boughdiriella  chouetensis  gen.  nov.  et  sp.  nov.  Further,  the  revision  of  the  type  specimens  of
D. astillerensis and Durangites of the D. vulgaris group shows that the former species deserves a new generic status, for
which Parrasiella gen. nov. is erected. Toucasiella, previously only known from Spain and Tunisia, is also reported for
the  first  time  from  south  east  France.  The  revision  of  the  “Mediterranean  Durangites”  supports  the  rejection  of  a
Durangites spp. Zone as part of the standard zonation for the upper Tithonian, and its replacement by the P. andreaei
Zone ( = D. vulgaris Zone sensu Sarti, 1988).

Key words: Himalayitidae, late Tithonian, Mexico,

ammonite faunas, taxonomy, Mediterranean Tethys.

C. intermedia Subzone and lower part of the C. colomi
Subzone.

However, both papers lack description of the fauna that

supports rejection of the use of a Durangites spp. Zone in the
standard  zonation  of  the  upper  Tithonian  (Geyssant  1997).
Thus,  in  the  present  paper,  special  attention  is  given  to
“Mediterranean  Durangites”, that are either reinterpreted as
juvenile and microconch forms of Protacanthodiscus and/or
Boughdiriella gen. nov. Detailed examination of Durangites
Burckhardt,  1912  supports  the  introduction  of  Parrasiella
gen. nov. for the peculiar Durangites of the D. astillerensis
group  Imlay,  1939.  Finally,  the  first  report  of  Toucasiella
Enay, Boughdiri & Le Hégarat, 1998a in southeastern France
sheds light on the phylogeny of late Tithonian himalayitids.

Geological setting

The reader is referred to the work of Wimbledon et al.

(2013)  and  Bulot  et  al.  (2014)  for  further  details  about
the  lithology,  biostratigraphy  (ammonites,  calpionellids  and
calcareous  nannofossils)  and  magnetostratigraphy  of  the
Le Chouet section. To avoid redundancy, we chose to synthe-
size the data discussed herein on Fig. 1. A map of the Mexi-
can  localities  is  presented  on  Fig. 2  and  their  geological
descriptions  are  to  be  found  in  Burckhart  (1912),  Imlay
(1939), Verma & Westermann (1973) and Olóriz et al. (1999).

119

TAXONOMY OF UPPER TITHONIAN HIMALAYITID AMMONITES FROM LE CHOUET

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

Systematic paleontology

All dimensions of specimens are given in millimetres:

Dmax = larger measurable diameter, D = diameter, Wh = whorl
height, U = umbilical diameter. Ratios such as Wh/D and U/D
are dimensions as a percentage of the diameter at the point of
measurement.  The  suture  terminology  is  that  of  Korn  et  al.
(2003).  The  bed  numbers  for  the  Le  Chouet  section  follow
that  of  Wimbledon  et  al.  (2013)  and  Bulot  et  al.  (2014)  as
shown on Fig. 1.

Acronyms. Unless otherwise mentioned, all specimens are

deposited in the Frau/Bulot collection at the Musée Paléon-
tologique de Provence (MPP) of Aix-Marseille University.
Other specimens studied herein are deposited in the paleon-
tological collections of the Universidad Nacional Autonoma
de Mexico (UNAM), University of Michigan (U.M.) and
University of Lyon-1 (FSL).

Order: Ammonitida Fisher, 1882

Suborder: Ammonitina Fisher, 1882

Superfamily: Perisphinctoidea Steinmann, 1890

Family: Himalayitidae Spath, 1925

Genus: Durangites Burckhardt, 1912

Type species: Durangites vulgaris Burckhardt, 1912, by

subsequent designation of Cantú-Chapa (1968, p. 22).

When introducing his new genus, Burckhardt (1912) did not

designate a type species. The subsequent designation as type
species of Durangites acanthicus Burckhardt, 1912 by Roman
(1938, p. 323) is invalid under article 67.5 of the I.C.Z.N. As
already pointed out by Cantú-Chapa (1968, p. 22) and Verma
& Westermann (1973, p. 253—254), Durangites acanthicus is
a problematic species based on a single, incomplete and
poorly preserved specimen that only shows two of the four

ornamental stages that characterize the genus Durangites as it
was originally defined by Burckhardt (1912, p. 144).

On the contrary, re-examination of the well-preserved type

series of Durangites vulgaris shows that this species exhibits
the four ornamental stages that were given in the original
definition. As a consequence, the designation of D. vulgaris
as type species of Durangites by Cantú-Chapa (1968, p. 22)
should be considered as valid, albeit for the wrong reasons.

The lectotype (UNAM IGM 504) of D. vulgaris Burck-

hardt (1912, pl. 37, figs. 1, 2, 5, 18, refigured herein Fig. 3B)
by subsequent designation of Tavera (1985, p. 158) is unfor-
tunately  lost  (Moreno-Bedmar,  personal  communication,
2014). According to article 72.4 of the I.C.Z.N., the type se-
ries is composed by all the specimens figured by Burckhardt
(1912) on pl. 37, figs. 1—35 and pl. 38, figs. 1—4, as well as
any  other  specimen  mentioned  in  the  text.  For  the  reasons
given above, we designate as neotype the specimen UNAM
IGM 504a of Burckhardt (1912, pl. 37, figs. 3, 4, 6, 9), re-il-
lustrated  herein  (Fig. 3B).  This  designation  is  in  agreement
with article 75.3 of the I.C.Z.N.

Emended diagnosis: Small-sized planulate ammonites

with  a  compressed  shell  and  a  deep  evolute  umbilicus
(0.34 < U/D < 0.45).  Rounded  to  sub-quadrate  whorl  section
with  well-defined  umbilical  wall.  When  preserved,  body
chamber  generally  occupies  almost  half  of  the  last  whorl.
Ornamentation  varies  through  ontogeny  and  three  different
stages can be recognized.

Primary stage (D < 10 mm) characterized by straight and

fine ribs, simple or bifurcate on the upper third of the flank;
feeble lateral and small ventro-lateral tubercles; deep smooth
ventral sulcus (“stade microcanthus” and “stade Köllikeri”
of Burckhardt).

Secondary stage marked by straight simple and intercala-

tory ribs mostly divided on upper part of the flank; dis-

Fig. 2. Map of the Mexican type localities of Durangites Burck-
hardt, 1912 and Parrasiella gen. nov.

120

FRAU, BULOT and WIMBLEDON

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

appearance of lateral tubercles; development of prominent
radially elongated ventro-lateral tubercles; smooth ventral
furrow (“stade typique” of Burckhardt).

Final stage characterized by mostly divided radiate to rur-

siradiate ribs; progressive disappearance of the ventro-lateral
tubercles and replacement of smooth ventral furrow by a
flattened ventral band with weakened ribs that may curve
adorally (“stade adulte” of Burckhardt).

Suture line simple with bifid external lobe and trifid ad-

ventive lobe; large asymmetrical external saddle with higher
external branch (Fig. 3C and D).

Dimorphism: The existence of dimorphic pairs in Mexi-

can Durangites was suggested by Verma & Westermann
(1973, p. 254). A re-examination of the material illustrated by
Burckhardt (1912) allows us to distinguish two morphotypes.

Fig. 3. Durangites vulgaris Burckhardt, 1912. A – The lost lectotype of D. vulgaris reproduced after Burckhardt (1912, pl. 37, figs. 1, 2, 5);
B – The neotype IGM 504a, MPIG; C – Suture line (

×2) of the lost lectotype reproduced after Burckhardt (1912, pl. 37, fig. 18); D – Su-

ture line (

×2) of the neotype reproduced after Burckhardt (1912, pl. 37, fig. 6). Bar scale is 10 mm.

A first group of small-sized forms (Dmax < 40 mm) match

perfectly the diagnosis of the genus given above. This group
includes: D. vulgaris pro parte, D. acanthicus, D. latesellatus
Burckhardt, 1912, D. incertus Burckhardt, 1912 and D. nodu-
latus Burckhardt, 1912.

The other morphotype encompasses larger forms (Dmax

> 40 mm); it is characterized by distinctive secondary and fi-
nal growth stages marked by higher rib(s) densities, attenuated
tubercles, an individualized ventral band throughout onto-
geny, and by the scaphitoid shape to the outer whorls due to
the fast growth rate of the last whorl. This group includes: D.
vulgaris pro parte, D. humboldti Burckhardt, 1912, D. denses-
triatus Burckardt, 1912 and D. fusicostatus Burckhardt, 1912.
Additionally, D. coghlani (Aguilera in Castillo & Aguilera,
1895) and D. alencasteri Verma & Westermann, 1973 also

121

TAXONOMY OF UPPER TITHONIAN HIMALAYITID AMMONITES FROM LE CHOUET

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

belongs to this group. D. heilprini (Aguilera in Castillo &
Aguilera, 1895) merely corresponds to a juvenile of this
group.

Even if the features that suggest the distinction of the two

morphological  variants  strongly  suggest  intrageneric  sexual
dimorphism,  the  preservation  of  Mexican  specimens  allows
no sign of a differentiated peristome that could support such
an interpretation. Moreover, even though the great majority
of  the  specimens  were  collected  at  Cerro  de  Las  Liebres,
Burckhardt (1912, p. 220—221) clearly stated that the thick-
ness of the “couches à Durangites” of the San Pedro del Gallo
area (Durango State) exceeds 100 metres. It is therefore not
possible  to  assume  that  the  taxa  are  synchronous,  even
though  Imlay  (1939,  p. 15  and  18)  suggested  that  the  speci-
mens collected by Burckhardt originated from a limited num-
ber  of  phosphatic  limestone  concretions.  If  so,  the  Mexican
taxa listed above may only represent typological morphotypes
of a single paleobiological species.

It should be noted that Enay et al. (1998b) proposed sexual

dimorphism between the genera Durangites and Protacan-
thodiscus. This view is not retained herein and will be dis-
cussed below.

Specific content: In our opinion, Durangites should be

strictly restricted in its scope to the species listed above, as
illustrated by Aguilera in Castillo & Aguilera (1895), Burck-
hardt (1912), Verma & Westermann (1973) and Olóriz et al.
(1999).

Durangites zigzagcostatus Cantú-Chapa, 2006 is based on

juvenile specimens with dense ribbing that forms a chevron
across the venter. These specimens most likely belong to the
group of “Kossmatia” victoris (Burckhardt, 1906).

Durangites astillerensis Imlay, 1939, and the species D.

juanensis,  D.  latiumbilicatum  and  D.  galeanense  described
by Cantú-Chapa (1968) should be excluded from Durangites
because they do not show the succession of ontogenetic stages
which we describe above and which will be further discussed
in the description of Parrasiella gen. nov. section of this pa-
per. D. vulgaris and D. cf. D. acanthicus from Cuba illus-
trated by Imlay (1942, pl. 3, figs. 1, 5—7) belong to the same
group. Moreover, they belong to a very specific assemblage
dominated  by  Salinites  Cantú-Chapa,  1968,  a  genus  that
never  occurs  in  the  classical  “Kossmatia”—Durangites—
“Corongoceras”  assemblage  of  San  Pedro  del  Gallo  and
Sierra de Catorce. Durangites rarifurcatus Imlay, 1939 also
seems to be related to Parrasiella gen. nov.

Other records from Cuba (Myczynski, 1989) and California

(Anderson, 1945) are based on material too poorly preserved
for identification.

Outside the New World, Durangites has been reported

from the Mediterranean (Enay et al. 1971; Enay & Geyssant
1975;  Cecca  et  al.  1983;  Tavera  1985),  Bulgaria  (Ivanov  et
al.  2010),  India  (Shome  &  Bardhan  2009),  and  the  Russian
Pacific coast (Sey & Kalacheva 1983). In our opinion none
of these records truly belong to Durangites. The Mediterra-
nean occurrences will be addressed in detail in the Protacan-
thodiscus and Boughdiriella gen. nov. sections of this paper.
Durangites  cf.  heilprini,  Durangites.  sp.  A  and  Durangites
sp.  from  Kutch  (India,  Shome  &  Bardham  2009)  falls  into
the range of variation of Micracanthoceras brightoni Spath,

1931. Finally, preservation of the Durangites sp. ind. from
Primorye (Sey & Kalacheva 1983, pl. 2, fig. 5) does not al-
low identification at the genus level.

Occurrence: Since the work of Enay et al. (1971) and

Enay & Geyssant (1975), Durangites has been considered as
a widespread key genus defining the top of the Tithonian
Stage. This view needs to be completely reconsidered in the
light of the taxonomic opinions presented herein.

As herein understood, Durangites is a strictly Mexican ge-

nus and is a major element of the “Kossmatia”—Durangites—
“Corongoceras”  assemblage  of  Verma  &  Westermann
(1973): an assemblage that was originally considered to be a
late Tithonian fauna, based on the study of the Caja Forma-
tion (Sierra de Catorce). According to the preliminary revi-
sion  of  Olóriz  et  al.  (1999),  Durangites  is  restricted  and
dominant  in  the  upper  part  of  the  Caja  Formation  where  it
co-occurs with less frequent Substeueroceras and rare “Kos-
smatia”.  Calibration  with  calpionellids  at  this  locality  indi-
cates  a  late  early  to  middle  Berriasian  age  for  this  fauna
(Olóriz  et  al.  1999).  A  Substeueroceras-Durangites  assem-
blage was also reported by Adatte et al. (1994a,b, 1996) just
below the  Crassicollaria/Calpionella zones boundary  sensu
Remane et al. (1986). Therefore, the first occurrence of Du-
rangites in the late late Tithonian cannot be ruled out. Never-
theless,  it  should  be  noted  that  the  base  of  the  Calpionella
Zone  is  ill  defined  in  the  sections  studied  (Adatte  et  al.,
1996, p. 679) and that with the exception of a single doubtful
specimen (Durangites sp. in Adatte et al. 1994b, pl. 2, fig. 5)
the fauna is still to be formally documented.

Genus Parrasiella gen. nov.

Type species: Durangites astillerensis Imlay, 1939.
Derivation of name: From Sierra de Parras, a north-

central region of Mexico.

Diagnosis: Small-sized discoidal ammonite with a shal-

low and wide open umbilicus (0.40<U/D<0.47). Sub-rounded
to ovate whorl section, with convex flank. Body chamber
generally occupies almost half of the last whorl. Highly dis-
tinctive ornamentation of bifurcated and parabolic ribs at the
end of the phragmocone. Posterior branches of bifurcate ribs
marked by radially elongated ventro-lateral tubercles that de-
limit a shallow ventral band. Body chamber ornamentation
composed of bifurcate and simple rursiradiate ribs that cross
the venter with a slightly weakening.

Specific content: Beside the type species, Parrasiella

gen. nov. comprises Durangites rarifurcatus Imlay, 1939;
Durangites galeanense Cantú-Chapa, 1968; Durangites la-
tiumbilicatum Cantú-Chapa, 1968 and Durangites juanensis
Cantú-Chapa, 1968.

Remarks: The type species of Parrasiella gen. nov. has

previously been included in the genus Durangites following
the work of Imlay (1939, 1942) and Cantú-Chapa (1968). As
herein  understood,  the  genus  Parrasiella  differs  by  its  evo-
lute  coiling,  shallow  umbilicus,  rounded  whorl  section
throughout  ontogeny  and  the  regular  disposition  of  ventro-
lateral  tubercles  on  the  phragmocone.  In  the  literature,  the
type species of Parrasiella gen. nov. has been reported from
the  western  Tethys  (Boughdiri  1994;  Enay  et  al.  1998b;

123

TAXONOMY OF UPPER TITHONIAN HIMALAYITID AMMONITES FROM LE CHOUET

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

Ivanov et al. 2010). In our view, none of the specimens illus-
trated are actually of the Mexican species: these will be dis-
cussed in the Boughdiriella gen. nov. section of this paper.

Occurrence: According to Imlay (1939, p. 5), Parrasiella

astillerensis co-occurs with Salinites grossicostatum (Imlay,
1939), Salinites ecarinatum (Imlay, 1939), and misidentified
Durangites cf. acanthicus. At locality K2, Imlay (1939) re-
ported Durangites rarifurcatus in association with Salinites.
In Mexico, D. galeanense, D. latiumbilicatum and D. juanen-
sis were also described in association with S. grossicostatum
by Cantú-Chapa (1968).

The age of the Salinites Cantú-Chapa, 1968 and Parrasiella

gen.  nov.  assemblage  is  unclear  and  the  two  genera  are  not
members  of  the  classical  “Kossmatia”—Durangites—“Coron-
goceras”  assemblage  of  San  Pedro  del  Gallo  and  Sierra  de
Catorce (Mexico).

In Cuba, Myczynski (1999) reports Salinites at the base of

the upper part of the La Zarza member above the “Vinalesi-
tes—Protancyloceras”  assemblage,  and  from  the  El  Ameri-
cano  member.  According  to  Myczynski  &  Pszczółkowski
(1994)  and  Myczynski  (1999),  both  units  are  of  late  Titho-
nian age based on the presence of tintinnoids. However, this
age has been much debated (see Cobiella-Reguera & Olóriz
2009,  with  references).  According  to  the  last-cited  authors,
the  upper  part  of  the  El  Americano  member  belongs  to  the
upper  Crassicollaria and/or Calpionella  zones,  and  that  in-
dicates a late late Tithonian to early middle Berriasian age.

Parrasiella astillerensis (Imlay, 1939)

Fig. 4J

1939 Durangites astillerensis n. sp. – Imlay, p. 46, pl. 10, figs. 10—12

Types: by original designation, According to Imlay (1939,

p. 46), the holotype is the specimen U.M. 17707. It is herein
re-illustrated (Fig. 4J). Imlay (1939) designated as paratype
another specimen (U.M. 20008).

Type locality: Both specimens originate from locality 34

of Imlay (1939) in the Sierra de Parras (Coahuila, north-cen-
tral Mexico) from the La Casita formation.

Remarks: The type specimen of Parrasiella astillerensis

bears long lateral necked lappets. It should be noted that the
other species are only known from a few specimens with no
aperture visible. In our view, P. latiumbilicatum and P. juan-
ensis  described  by  Cantú-Chapa  (1968)  are  closely  related
to, if not synonyms of, Parrasiella astillerensis. It should be
noted that the ornamentation of the early whorls of P. astille-
rensis matches well that seen in P. rarifurcatus and P. galea-
nense. Both taxa are characterized by a larger adult size, but
their  apertures  are  unknown.  Pending  new  studies  on  the
Mexican  faunas,  these  species  could  represent  the  macro-
conch of P. astillerensis.

Occurrence: Parrasiella astillerensis occurs in north-

central Mexico and western Cuba. As discussed above the
precise age of P. astillerensis is disputed.

Genus Boughdiriella gen. nov.

Type species: Boughdiriella chouetensis gen. et sp. nov.

Derivation of name: Dedicated to Mabrouk Boughdiri,

Head of the Geological Sciences Department of Bizerte Uni-
versity (Tunisia), for his contribution to the systematics of
late Tithonian ammonites.

Diagnosis: Small-sized dimorphic ammonites with a dis-

coidal and evolute shell. Sub-circular whorl section in inner
whorls; compressed sub-oval whorl section in adult. Shallow
and moderately open umbilicus. Umbilical wall slightly con-
vex. Ornamentation of inner whorls (up to D ~ 10 mm) com-
posed by rigid, straight, simple ribs. From D ~ 15 mm to the
end of the body chamber, ribs flexuous, prominent and bifur-
cated on the upper third of the flanks. Scarce trifurcate, and
intercalated ribs. Venter marked by a shallow furrow. The
suture line is unknown.

Remarks: Understanding of the “Mediterranean Duran-

gites” has been based on a limited number of specimens il-
lustrated  by  Cecca  et  al.  (1983),  Tavera  (1985),  Boughdiri
(1994), Enay et al. (1998b), and Ivanov et al. (2010), speci-
mens  that  were  referred  to  D.  vulgaris  and/or  Parrasiella
astillerensis. Detailed examination of the important material
collected at Le Chouet shows that the similarities to Duran-
gites  and  Parrasiella  gen.  nov.  are  only  superficial.  Both
genera differ in their marked tuberculated stage on the ventral
area, distinctive whorl sections and steep umbilical margin.

Occurrence: P. andreaei Zone (base of the calpionellid

C. colomi Subzone), late Tithonian. Boughdiriella gen. nov.
is  known  from  Spain  (Tavera,  1985),  South  East  France
(Boughdiri 1994; Enay et al. 1998b – this paper) and Bul-
garia  (Ivanov  et  al.  2010).  Potential  occurrence  in  Tunisia
(Boughdiri et al. 1999), Turkey (Enay et al. 1971), Italy (Sarti,
1995)  and  Morocco  (Benzaggagh  &  Atrops  1997,  p. 158)
needs to be illustrated.

Boughdiriella chouetensis nov. sp.

Fig. 4A—I

1985 Durangites acanthicus Burckhardt – Tavera, p. 156, pl. 18, fig. 11
1994 Durangites (Durangites) n. sp. 5 – Boughdiri, p. 123—128, pl. 1,

figs. 24, 28—32

1994 Durangites (Durangites) astillerensis Imlay – Boughdiri, pl. 1,

figs. 20—23

1998b Durangites (Durangites) gr. astillerensis Imlay – Enay et al.,

fig. 2, n° 17

1998b Durangites (Durangites) astillerensis Imlay – Enay et al., fig. 2,

n° 12

1998b Durangites (Durangites) aff. astillerensis Imlay – Enay et al.,

fig. 2, n° 1—3

1998b Durangites (Durangites) vulgaris Burckhardt – Enay et al., fig. 2,

n° 4

1998 Durangites (Durangites) sp. – Enay et al., fig. 2, n° 5
2010 Durangites (Durangites) aff. astillerensis Imlay – Ivanov et al.,

pl. 3, fig. 5

Type: The holotype is the specimen MPP-CHT.21/65

herein illustrated on Fig. 2A.

Paratypes: MPP-CHT.18/12, MPP-CHT.21/17, MPP-

CHT.21/18, MPP-CHT.21/23, MPP-CHT.19/29, MPP-
CHT.21/28, MPP-CHT.21/29, MPP-CHT.21/33.

Derivation of name: After Le Chouet.
Type locality: Le Chouet, near Les Près (Drôme, France).
Diagnosis: Small-sized dimorphic ammonites with a dis-

coidal and evolute shell. Sub-circular whorl section in inner

124

FRAU, BULOT and WIMBLEDON

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

whorls; compressed sub-oval whorl section in adult. Shallow
and moderately open umbilicus. Umbilical wall slightly con-
vex. Ornamentation of inner whorls (up to D ~10 mm) com-
posed by rigid, straight, simple ribs. From D ~15 mm to the
end of the body chamber, ribs flexuous, prominent and bifur-
cated on the upper third of the flanks. Scarce trifurcate, and
intercalated ribs. Venter marked by a shallow furrow. The
suture line is unknown.

Measurements: See Table 1.
Remarks: Although there is no significant ornamental

and/or size difference between micro- and macroconchs,
sexual dimorphism is recognizable. Microconchs are charac-
terized by short lateral lappets (Fig. 4A,B,D and E) while
macroconchs show a collared aperture (Fig. 4F,G and H).

Compared to Durangites vulgaris, Boughdiriella choueten-

sis gen. et sp. nov. is easily distinguished by its compressed
sub-rectangular whorl section and the absence of a short
stage with tubercles on the venter.

Specimens of B. chouetensis illustrated in the literature have

generally been assigned to Parrasiella astillerensis. That spe-
cies differs in its open umbilicus, sub-oval whorl section, and
a phragmocone end that has a prominent and long tubercu-
lated section on its venter. The phragmocone – body cham-
ber transition is marked by ‘pinched’ ventro-lateral tubercles.

Hegaratia busnardoi Patrulius & Avram, 1976 shows

some superficial similarities to B. chouetensis, but it can be
easily distinguished by its higher U/D ratio, coarse bifurcate
ribs and lateral constrictions.

Berriasella (Picteticeras) jauberti (Mazenot, 1939) shows

morphological similarities with B. chouetensis, but differs in
its larger adult size (60 to 85 mm), evolute coiling, sub-rectan-
gular whorl section throughout ontogeny and higher rib density.

Occurrence: As for the genus. At Le Chouet, B. choue-

tensis occurs at the top (e.g. beds 82 to 85) of the P. andreaei
Zone (base of the calpionellid C. colomi Subzone), late Ti-
thonian.

Genus Protacanthodiscus Spath, 1923

Type species: Hoplites andreaei Kilian, 1889; by origi-

nal designation.

Emended diagnosis: Middle to large-sized (Dmax

< 165 mm)  dimorphic  ammonites  with  an  open  (0.40 < U/
D < 0.50) and relatively deep umbilicus in the adult stage. Sub-
circular whorl section, with convex flanks on juveniles, which
become  progressively  sub-rectangular  to  sub-hexagonal  on
adults. Ornamentation mainly composed of bifurcate, and tri-
furcate  ribs  with  a  tubercle  at  the  furcation  point.  Some  ribs
can be looped. On the body chamber, bifurcate ribs are ended
on the ventral shoulder by a latero-ventral tubercle on the first,
or occasionally the second, branch. Ventral area marked by a
more or less flattened ventral band, depending on the shape of
the whorl section. Suture line is simple with large trifid lateral
lobe, which is as deep as the external lobe.

Dimorphism: Roman (1936, p. 22) gave the first diagno-

sis  of  Protacanthodiscus,  subsequently  emended  by  Tavera
(1985, p. 197). In the opinion of the latter author, Protacan-
thodiscus  is  a  dimorphic  genus.  In  his  unpublished  thesis,
Boughdiri  (1994)  reconsidered  the  systematic  content  of

Protacanthodiscus and included it as a subgenus of Durangi-
tes accommodating macroconch forms. Subsequently, Bough-
diri (personal communication, 2011) suggested that the
“Mediterranean Durangites” figured by Tavera (1985) could
be: “inner whorls and/or juveniles of other species that
would belong to other closely allied genera” (english transla-
tion). The present study supports this opinion (see synonymy
list of Protacanthodiscus andreaei). Moreover, the compara-
tively expanded succession at Le Chouet shows that the first
occurrence of Protacanthodiscus occurs at a lower level than
that of Boughdiriella gen. nov., that was until now regarded
as a “Mediterranean Durangites”.

The hypothesis of sexual dimorphism between true Duran-

gites and Protacanthodiscus is also to be ruled out in Mexico,
where no Protacanthodiscus stricto sensu have been collected
in association with Durangites (see Verma & Westermann
1973). Contrary to the opinion of Boughdiri (1994) and Enay
et al. (1998b), we consider that Acanthodiscus euthymiformis
Burckhardt, 1912 and Acanthodiscus transatlanticus Burck-
hardt, 1912 cannot be included in Protacanthodiscus.

Remarks: Spath (1923, p. 305) introduced the genus

Protacanthodiscus (based on Hoplites andreaei Kilian, 1889)
without  diagnosis  and  specific  content.  When  creating  the
family  Himalayitidae  (Spath,  1925,  p. 144),  Spath  included
Hoplites incompositus Retowski, 1893 in  Protacanthodiscus.
This species has since been transferred to the Neocomitidae
(Bogdanova  et  al.  1984;  Khimchiashvili  1989);  and  the  de-
scription  and  the  original  figure  leave  no  doubt  that  the
H. incompositus is a neocomitid species.

Tavera (1985), considered that Hoplites heterocosmus

Canavari, 1899 and Hoplites bonarellii Canavari, 1899 belong
to  Protacanthodiscus,  and  he  described  four  news  species
from  the  Betic  Cordilleras:  Protacanthodiscus  coronatus
Tavera, 1985; P. darwini Tavera, 1985;  P. nodosus Tavera,
1985; and P. berriasensis Tavera, 1985.

The expanded conception of Protacanthodiscus of Bough-

diri (1994) was only partly accepted by Enay et al. (1998a,b)
and Boughdiri et al. (1999). Despite the introduction of
Kilianites by Enay et al. (1998c) (type species: P. canavarii
Enay, Boughdiri & Le Hégarat, 1998c) and Hegaratites
Boughdiri, Enay & Le Hégarat, 1999 (type species: Hegara-

Table 1: Measurements of Boughdiriella chouetensis gen. and sp.
nov. U/D and Wh/D ratios are dimensions as a percentage of the dia-
meter at the point of measurement.

Specimen D

U/D

Wh/D

CHT 19–26

0.39

0.32

CHT 19–16

29 11 12 0.41

0.38

CHT 19–19

/ 12 18 / /

CHT 19–26

0.39

0.32

CHT 19–29

36 11 15 0.42

0.31

CHT 18–12

8.5

9.5

0.37

0.33

CHT 21–22

30 10 13 0.43

0.33

CHT 21–23

/ 12 18 / /

CHT 21–24

38 12 17 0.45

0.32

CHT 21–64

/ 11 / / /

CHT 21–83

0.40

0.35

CHT 21–93

29 11 13 0.45

0.38

CHT 21–94

18.5

0.43

0.32

125

TAXONOMY OF UPPER TITHONIAN HIMALAYITID AMMONITES FROM LE CHOUET

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

tites rheouisensis Boughdiri, Enay & Le Hégarat, 1999); the
exact content of Protacanthodiscus remained unclear for
those authors.

Based on the material at our disposal, we consider that P.

andreaei  shows  a  large  morphological  intraspecific  variab-
ility that encompass the typological species P. coronatus, P.
darwini  and  P.  nodosus.  Further,  examination  of  Neoperi-
sphinctes falloti Tavera (non Kilian, 1889); Durangites sin-
gularis Tavera, 1985; Durangites sutneroides Tavera, 1985;
D.  gigantis  Tavera,  1985  and  Durangites  apertus  Tavera,
1985, suggest that these species also fall in the range of vari-
ation of Protacanthodiscus andreaei.

Contrary to the opinions of Boughdiri (1994) and Enay et

al.  (1998b),  we  consider  that  Hoplites  macphersoni  Kilian,
1889  and  H.  malladae  Kilian,  1889  are  in  need  of  a  proper
revision and cannot be included in  Protacanthodiscus.  This
is also the case for Hoplites heterocosmus and H. bonarellii,
originally described by Canavari (1899).

Occurrence of Protacanthodiscus in the New World is

based on material described by Steuer (1897), Anderson (1945),
Leanza (1945, 1968), Rivera (1951), Cantú-Chapa (1967) and
Imlay & Jones (1970). As already suggested by Klein (2005),
the taxonomy of those forms is doubtful. Examination of the
type material of Hoplites quadripartitus Steuer, 1897, Prota-
canthodiscus pacificum Rivera, 1951 and P. puenteingaensis
Rivera, 1951 has convinced us that these species are homeo-
morphic with true Protacanthodiscus and that they deserve a
generic status in their own right. This systematic problem will
be addressed elsewhere, as part of the revision of the fauna
from the Puente Inga formation (Lima Coast, Peru).

Specific content: Protacanthodiscus andreaei (and its

synonyms:  Hoplites  (Acanthodiscus)  andreaei  Kilian  var.
punica Pervinquière, 1907; Protacanthodiscus coronatus, P.
darwini,  P. nodosus,  Durangites singularis,  D.  sutneroides,
D.  gigantis,  and  D.  apertus),  P.  savornini  (Roman,  1936),
Protacanthodiscus berriasensis and “Corongoceras” hexago-
nus Tavera, 1985.

Occurrence: At Le Chouet, Protacanthodiscus is re-

stricted to the uppermost Tithonian (top of the calpionellid
C. intermedia Subzone and lower part of the C. colomi Sub-
zone). In Spain, occurrence of P. berriasensis in the E. cula-
rensis horizon (base of the B. jacobi Zone) suggests that the
genus occurs as a rarity in the middle part of the C. colomi
Subzone. To our knowledge, the genus is reported from SE
France, Italy, Spain, Bulgaria, Morocco, Tunisia and Algeria.

Protacanthodiscus andreaei (Kilian, 1889)

Figs. 5A—L, 6A—E and 7A—C

1889 Hoplites Andreaei – Kilian, p. 670, pl. 32, fig. la,b
1889 Hoplites (Acanthodiscus) Andreaei Kilian var. Punica – Pervin-

quière, p. 38, pl. 2, fig. l2a,b

pars 1939 Berriasella Andreaei (Kilian) – Mazenot, p. 96, pl. 12,

fig. la,b, non fig. 4a,b

non 1960 Berriasella (Protacanthodiscus) aff. andreaei (Kilian) – Colli-

gnon, pl. CLXV, fig. 665

non 1960 Berriasella (Protacanthodiscus) aff. andreaei var. variabilis

Collignon, pl. CLXV, figs. 666, 667

?1960 Protacanthodiscus andreaei (Kilian) – Christ, p. 125, pl. 9, fig. 5
1979 Protacanthodiscus andreaei (Kilian) – Sapunov, p. 1985, pl. LVII,

fig. 6

1983 Durangites acanthicus Burckhardt – Cecca et al., p. 128, pl. 5,

fig. 1a,b

1985 Protacanthodiscus andreaei (Kilian) – Tavera, p. 198, pl. 26,

figs. 5a,b, 6, text-fig. 15H

1985 Protacanthodiscus sp. 1 gr. andreaei (Kilian) – Tavera, p. 199,

pl. 26, figs. 1a,b, 2, text-fig. 15E,I, text-fig. 12H

1985 Protacanthodiscus berriasensis n. sp. – Tavera, p. 206, pl. 26,

fig. 1a,b, pl. 28, fig. 1a,b, text-fig. 15D

1985 Protacanthodiscus coronatus n. sp. – Tavera, p. 200, pl. 27,

fig. 1a,b, text-fig. 15A

1985 Protacanthodiscus darwini n. sp. – Tavera, p. 203, pl. 26, figs. 3, 4,

text-fig. 15B

1985 Protacanthodiscus nodusus n. sp. – Tavera, p. 202, pl. 27, fig. 2,

text-fig. 15C

1985 Durangites singularis n. sp. – Tavera, p. 168, pl. 17, figs. 6—9, text-

fig. 12E

pars 1985 Durangites sutneroides n. sp. –Tavera, p. 168, pl. 18, figs. 1, 2,

3, 5, non fig. 4a,b

1985 Durangites heilprini (Aguilera) – Tavera, p. 164, pl. 18, figs. 6, 7,

text-fig. 12G

1985 Durangites gigantis n. sp. – Tavera, p. 162, pl. 18, figs. 8, 9, text-

fig. 12A,B

1985 Durangites acanthicus Burckhardt – Tavera, p. 156, pl. 18,

figs. 10a,b, 11, text-fig. 12C

1985 Durangites vulgaris Burckhardt – Tavera, p. 157, pl. 18, figs. 12,

13a,b, text-fig. 12I

1985 Durangites apertus n. sp. – Tavera, p. 161, pl. 18, figs. 14, 15a,b,

text-fig. 12F

1985 Durangites cf. astillerensis Imlay – Tavera, p. 166, pl. 18, fig. 16,

text-fig. 12D

1985 Neoperisphinctes falloti (Kilian) – Tavera, p. 132, pl. 16, fig. 10a,b
1994 Protacanthodiscus (Protacanthodiscus) andreaei (Kilian) – Bough-

diri, p. 147, pl. 3, figs. 1a,c, 3a,b, pl. 4, fig. 2

1994 Protacanthodiscus (Protacanthodiscus) n. sp. A – Boughdiri,

p. 208, pl. 3, fig. 5

1994 Protacanthodiscus (Protacanthodiscus) n. sp. 3 – Boughdiri,

p. 168, pl. 3, fig. 7

1994 Protacanthodiscus (Protacanthodiscus) n. sp. 4 – Boughdiri,

p. 170, pl. 2, fig. 17

1994 Protacanthodiscus (Protacanthodiscus) n. sp. 7 – Boughdiri,

p. 176, pl. 3, fig. 2

1994 Protacanthodiscus (Protacanthodiscus) n. sp. 11 – Boughdiri,

p. 186, pl. 3, fig. 6

1994 Protacanthodiscus (Protacanthodiscus) n. sp. 12 – Boughdiri,

p. 188, pl. 4, fig. 1

1994 Protacanthodiscus (Protacanthodiscus) coronatus (Tavera) –

Boughdiri, p. 151, pl. 4, figs. 6, 7

1994 Durangites (Durangites) humboldti (Burckhardt) – Boughdiri,

p. 99, pl. 1, figs. 33a,b, 34

1994 Durangites (Durangites) juanense (Cantú-Chapa) – Boughdiri,

p. 106, pl. 1, fig. 34

1998b Durangites (Protacanthodiscus) andreaei (Kilian) – Enay et al.,

figs. 2, n° 16a,b ( = Kilian, 1889, pl. 32, fig. la,b)

1998b Durangites (Durangites ) juanensis Cantú-Chapa – Enay et al.,

figs. 2, n° 6, 7 ( = Boughdiri, 1994, pl. 1, fig. 35)

1998b Durangites (Durangites) humboldti Burckhardt – Enay et al.,

figs. 2, n° 8—10a,b

1998b Durangites (Protacanthodiscus) sp. – Enay et al., figs. 2, n° 11
1998b Durangites (Protacanthodiscus) apertus (Tavera) – Enay et al.,

figs. 2, n° 13—14

2010 Protacanthodiscus cf. andreaei (Kilian) – Ivanov et al., pl. 3, fig. 3
2010 Durangites aff. fusicostatus Burckhardt – Ivanov et al., pl. 3,

fig. 1a,b

2010   Durangites cf. vulgaris Burckhardt – Ivanov et al., pl. 3, fig. 2a,b
2010   Durangites singularis Tavera – Ivanov et al., pl. 3, fig. 4
2010   Protacanthodiscus apertus (Tavera) – Benzaggagh et al., fig. 5i
2010   Durangites humboldti Burckhardt – Benzaggagh et al., fig. 5n
non 2013 Protacanthodiscus coronatus (Tavera) – Szives & Fözy, p. 301,

pl. 1, figs. 2, 4 ( = Himalayitidae gen. nov. et sp. nov.)

non 2013 Protacanthodiscus andreaei (Kilian) – Szives & Fözy, p. 300,

pl. 5, fig. 4a,b, pl. 6, fig. 5a,b, pl. 8, fig. 10a,b ( = Himalayitidae gen.
nov. et sp. nov.)

non 2013 Protacanthodiscus andreaei (Kilian) – Fözy & Scherzinger,

p. 257 ( = Himalayitidae gen. nov. et sp. nov.)

127

TAXONOMY OF UPPER TITHONIAN HIMALAYITID AMMONITES FROM LE CHOUET

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

Table 2: Measurements of Protacanthodiscus andreaei (Kilian).
U = umbilical diameter, Wh = whorl height, D = diameter. U/D and
Wh/D ratios are dimensions as a percentage of the diameter at the
point of measurement.

Holotype: The specimen illustrated by Kilian (1889, p. 670,

pl. 32, fig. la,b) from the De Verneuil collection (FSL.13056).
It was re-illustrated by Enay et al. (1998b, figs. 2—16a,b).

Material:

Measurements: See Table 2.
Description: A detailed examination of the material at

our disposal reveals marked sexual dimorphism. Microconchs
(Dmax < 50 mm) exhibit three ontogenetic stages:

On inner whorls (D<15 mm), the ornamentation is com-

posed of straight, rigid, prosiradiate ribs marked by small
punctiform shoulders at the furcation point;

To D ~ 30 mm, ornamentation is irregular, composed of

rigid bifurcate ribs. The furcation point is higher on the
flank. The umbilical wall and margin are more abrupt. The
whorls section is sub-circular;

On the adult stage (D > 30 mm), ornamentation is charac-

terized  by  marked  irregular  ribbing.  Most  of  the  ribs  bifur-
cate  on  the  mid  flank  with  more  or  less  strong  lateral
tubercles at the furcation point. Generally, on bifurcate ribs,
the adoral branch is ended by a pinched ventro-lateral tuber-
cle on the axis of the coiling. At that stage, ribs can also be
simple, trifurcate, intercalated or looped. Several specimens
possess  regular  prosiradiate  and  flexuous  bifurcate  ribs  on
the body chamber. At the mouth of the shell, the whorl sec-
tion is more or less sub-oval to sub-rectangular.

Macroconchs (Dmax up to 165 mm) also show three onto-

genetic stages:

The juvenile stage is similar to that of the microconchs;
The intermediate stage can reach D ~ 50 mm. Compared to

the microconchs, this stage is marked by dense and flexuous
ribs. The furcation point is lower on the flank;

At the adult stage, two marked morphotypes can be distin-

guished. (1) A slender group characterized by a dense ribbing
and a sub-rectangular whorl section, higher than wide. The ribs
are mainly bifurcated and the tubercles are feeble or absent. The
ventral band is attenuated and the ribs can cross the venter with
a shallow weakening. (2) A robust group characterized by larger
size, an irregular and coarse ribbing pattern and a marked sub-
hexagonal whorl section with a flattened ventral area. Trifurcate
ribs are common, with massive tubercles at the furcation point.

Occurrence: Beds 79 to 85, P. andreaei Zone (top of

calpionellid C. intermedia Subzone and lower part of the C.
colomi  Subzone),  upper  Tithonian.  As  outlined  by  Tavera
(1985), the appearance and increase in abundance of the spe-
cies  is  gradual.  P.  andreaei  is  reported  from  South  East
Spain  and  France,  Italy,  Bulgaria,  Tunisia  and  Morocco.
Since  D.  vulgaris  Tavera  non  Burckhardt  is  herein  consid-
ered as a microconch of P. andreaei, the D. vulgaris Zone of
Sarti (1988) is a junior subjective synonym of the P. andreaei
Zone introduced by Wimbledon et al. (2013).

Protacanthodiscus hexagonus (Tavera, 1985)

Fig. 7D

1985 “Corongoceras” hexagonus Tavera, p. 195, pl. 28, figs. 3a,b, 4a,b,

text-fig. 17H

2010 Protacanthodiscus hexagonus Tavera – Benzaggagh et al., p. 309,

figs. 5, l-m

Type: The holotype is specimen T.Co.3.1. from the Tavera

collection, deposited in the collections of the University of
Granada.

Material: MPP-CHT.21/7.
Description: The single specimen shows the first onto-

genetic stage of the type-species of Protacanthodiscus. By
comparison to P. andreaei, the intermediate stage is very re-
duced and the morphology that characterizes the adult stage
of the robust macroconch occurs at a diameter similar to that
seen in small adult microconchs. Trifurcations and lateral
and ventral tubercles are prominent. The whorl section is al-
most sub-hexagonal.

Remarks: Tavera (1985) separated a group of “Corongo-

ceras”, based on “C.” hexagonus, seen as the phyletic link
between Corongoceras sensu lato ( = Ardesciella Bulot et al.
2014) and Protacanthodiscus. This view is not supported by

Specimen D

U/D

Wh/D

CHT 15–04

/ 17.5 / / /

CHT 15–06

40 17 15 0.38

0.43

CHT 15–21

40 15 16 0.40

0.38

CHT 18–01

CHT 18–20

/ 15 / / /

CHT 19–07

8.5

0.35

CHT 19–12

0.37

0.32

CHT 19–13

36 14.5

15 0.42

0.40

CHT 19–14

31 12 / / 0.39

CHT 19–15

37 13 18 0.49

0.35

CHT 19–24

38 12.5

13 0.34

0.33

CHT 19–25

55 21 24 0.44

0.38

CHT 19–31

0.45

0.32

CHT 19–34

28.5 10.5 10 0.35 0.37

CHT 19–35

62 22 26 0.42

0.35

CHT 21–05

/ 20 / / /

CHT 21–07

32 11 12 0.38

0.34

CHT 21–16

/ / / / /

CHT 21–19

0.44

0.38

CHT 21–20

8.5

0.36

0.39

CHT 21–25

8.5

0.35

0.33

CHT 21–26

0.38

CHT 21–27

36 12 15 0.42

0.33

CHT 21–32

/ 14 15.5 / /

CHT 21–35

29.5 10.5 10 0.34 0.36

CHT 21–37

/ / / / /

CHT 21–38

37 23 22 0.59

0.62

CHT 21–39

/ / / / /

CHT 21–40

/ / / / /

CHT 21–41

70 28 28 0.40

0.40

CHT 21–57

12.5

0.37

0.38

CHT 21–62

41 14 17 0.41

0.34

129

TAXONOMY OF UPPER TITHONIAN HIMALAYITID AMMONITES FROM LE CHOUET

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

Fig. 7. Lateral (A), ventral (B) views, and whorl section at about D = 131 mm (C) of complete macroconch of Protacanthodiscus andreaei
(Kilian) from the late Tithonian (P. andreaei Zone) of Le Chouet: MPP-CHT.21/95 (bed 85). D – Protacanthodiscus hexagonus (Tavera)
from the P. andreaei Zone (bed 85) of Le Chouet: MPP-CHT.21/7. Toucasiella gerardi Enay et al., from the P. andreaei Zone of Le Chouet:
E – MPP-CHT.15/9 [m] (bed 79), F – MPP-CHT.15t/14 [m] (bed 79). Bar scale is 10 mm.

Genus Toucasiella Enay, Boughdiri & Le Hégarat, 1998a

Type species: Toucasiella gerardi Enay, Boughdiri, Le

Hégarat, 1998b; by original designation.

Toucasiella gerardi Enay, Boughdiri & Le Hégarat, 1998a

Fig. 7E—F

1994 Durangites (Durangites) mazenoti (Mazenot, 1939) non (Breistroffer,

1937) – Boughdiri, pl. 1, figs. 7, 8a,b, 11, 12

1998a Toucasiella gerardi n. sp. Enay et al., p. 471, figs. 1—21

Holotype: the unnumbered specimen illustrated by Enay

et al. (1998a, fig. 4) from Cabra (Spain).

Material: MPP-CHT.15t/14 and MPP-CHT.15/9.
Description: The specimen MPP-CHT.15/9 is an incom-

plete body-chamber of a typical microconch form. It shows
the extreme adult ornamental pattern of T. gerardi, with
strong and spaced simple ribs, ended by externo-lateral and
ventro-lateral tubercles (compare with fig. 18a—b in Enay et
al. 1998a). At the end of the body chamber, the whorl section
is sub-rectangular, the ventral furrow is weak and it is
crossed by the ribs.

130

FRAU, BULOT and WIMBLEDON

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

The specimen MPP-CHT.15t/14 perfectly matches the

morphological and ornamental pattern of the adult macro-
conch of T. gerardi, in its middling size, compressed section,
single and bifurcate ribs with lateral tubercles at the furca-
tion points (compare with fig. 8 in Enay et al. 1998a).

Remarks: According to Enay et al. (1998a), Toucasiella

gerardi is based on small-sized himalayitids from the M. mi-
crocanthum  Zone  (Chitinoidella  Zone)  of  south  east  Spain
and  central  Tunisia.  Our  specimens  originate  from  a  higher
level  at  the  base  of  the  P.  andreaei  Zone  (Crassicollaria
Zone, top of the C. intermedia Subzone).

However, it should be noted that Boughdiri et al. (1999,

p. 107) reported Toucasiella gerardi from bed RHS-4 in the
Sidi  Khalif  Formation  (Tunisia).  Due  to  the  dolomitization
of the lower part of that formation, there is no consensus on
the  calpionellid  biostratigraphic  scheme  at  the  base  of  the
upper  Tithonian  (see  Boughdiri  et  al.  1999,  fig. 2).  Thus,
there is no counter-argument to consider an expansion of the
C.  intermedia  Subzone  in  the  Sidi  Khalif  Formation.  This
hypothesis  is  more  consistent  with  the  calpionellids  data  at
Le Chouet (Wimbledon et al. 2013; Bulot et al. 2014).

Occurrence: Bed 79, P. andreaei Zone (top of the C. in-

termedia Subzone), upper Tithonian. Beside the well-docu-
mented occurrences in SE Spain and Tunisia, this is the first
report of the species in SE France.

Conclusion

Due to morphological convergence and misdated strati-

graphic occurrences, the taxonomy of himalayitid genera is
still at a very preliminary stage. The overlooked late Titho-
nian endemism of the family at the genus level is much higher
than was previously assumed in the literature. This is reflected
by our introduction of Parrasiella gen. nov. for Mexican and
Cuban species hitherto considered to be true Durangites. Evi-
dence suggests that the latter genus only occurs in the lower
to lower middle Berriasian of Mexico. As a consequence, the
use of Durangites as a marker for the late Tithonian should
be abandoned.

Also, none of the records of the genus in the Mediterranean

Tethys belong to Durangites: the great majority of these re-
ports refer to inner whorls and/or juveniles of Protacanthodis-
cus or to Boughdiriella chouetensis gen. et sp. nov. The record
of the himalayitids is very homogenous across the regions of
the Mediterranean and it is dominated by the highly variable
species Protacanthodiscus andreaei. As a result, the geo-
graphical and stratigraphical pattern of the species is very use-
ful in defining a zone at the top of the upper Tithonian.

Acknowledgments: This work is a contribution of the

Berriasian Working Group (BWG) of the International Sub-
commission on Cretaceous Stratigraphy (I.S.C.S.). Emmanuel
Robert (University of Lyon I), Istvan Fözy (Hungarian Natu-
ral History Museum), Josep Anton Moreno Bedmar (Univer-
sidad Nacional Autónoma de Mexico), Manuel Aldana
(INGEMMET, Lima, Peru) and Joachim Reitner (University
of Göttingen) are gratefully acknowledged for providing
missing references and access to type material. Valuable dis-

cussions  with  Mabrouk  Boughdiri  (University  of  Bizerte)
greatly  improved  this  paper.  Warm  thanks  are  due  to  the
Jean-Pierre  Lopez  and  Martine  Broin  families  (Le  Chouet
and Les Près, France) for their hospitality and friendship dur-
ing  our  fieldwork  seasons,  to  Cyprien  Lanteaume  (Aix-
Marseille  Université)  and  Emile  Hourqueig  (Toulouse)  for
continuous  support  to  one  of  us  (C.F.).  Comments  by  two
anonymous  reviewers  contributed  to  improvement  of  the
original manuscript.

References

Adatte T., Stinnesbeck W. & Remane J. 1994a: The Jurassic-Creta-

ceous boundary in Northeastern Mexico. Confrontation and
correlations by microfacies, clay mineral mineralogy, calpio-
nellids and ammonites. Géobios 17, 37—56.

Adatte T., Stinnesbeck W., Hubberten H. & Remane J. 1994b: Cor-

relaciones multiestratigráficas en el límite Jurásico—Cretácico
en el Noreste de México. Bol. Soc. Geol. México 51, 23—51.

Adatte T., Stinnesbeck W., Remane J. & Hubberten H. 1996: Paleo-

oceanographic change at the Jurassic—Cretaceous boundary in
the western Tethys, northeastern Mexico. Cretaceous Research
17, 671—689.

Anderson F.M. 1945: Knoxville Series in the California Mesozoic.

Geol. Soc. Amer. Bull. 56, 910—1014.

Benzaggagh M. & Atrops F. 1997: Stratigraphie et associations de

faune d’ammonites des zones du Kimméridgien, Tithonien et
Berriasien basal dans le Prérif interne (Rif, Maroc). Newslett.
Stratigr. 35, 127—163.

Benzaggagh M., Cecca F. & Rouget I. 2010: Biostratigraphy distri-

bution of ammonites and calpionellids in the Tithonian of the
internal Prerif (Msila area, Morocco). Paläont. Z. 84, 301—315.

Bogdanova T.N., Lobacheva S.V., Prozorovskii V.A. & Favorskaya

T.A. 1984: The Berriasian stage in the Eastern Crimea and the
Jurassic—Cretaceous Boundary. In: Menner V.V. (Ed.): The Ju-
rassic and Cretaceous boundary stages. Trans. Geol. Geophys.,
Siberian Branch of the Academy of Sciences of USSR 644,
28—36.

Boughdiri M. 1994: Les genres d’ammonites Durangites et Prota-

canthodiscus (Tithonien supérieur) dans la Téthys occidentale
(SE Espagne, SE France, Algérie et Tunisie). Stratigraphie,
Paléontologie et Biogéographie. Thèse, Univ. Claude Bernard
Lyon I, 1—268.

Boughdiri M., Enay R., Le Hégarat G. & Memmi L. 1999: Hegara-

tites nov. gen. (Ammonitina): Himalayitidae nouveau du Ti-
thonien supérieur da la coupe du Jebel Rhéouis (Axe nord—sud,
Tunisie centrale). Précisions stratigraphiques, approche phylé-
tique et signification biogéographique. Rev. Paléobiologie 18,
105—121.

Breistroffer M. 1937: Sur un remarquable gisement à fossiles pyri-

teux du Tithonique supérieur de Tunisie. C.R. Soc. Géol.
France, 18—20.

Bulot L.G., Frau C. & Wimbledon W.A.P. 2014: New and poorly

known Perisphinctoidea (Ammonitina) from the Upper Titho-
nian of Le Chouet (Les Près, Drôme, SE France). Volumina
Jurassica 12, 113—128.

Burckhardt C. 1912: Faunes jurassiques et crétaciques de San Pedro

del Gallo. Bol. Inst. Geol. México 29, 1—137.

Canavari M. 1899: Hopliti Titoniani dell Appennino centrale. Atti

Soc. Toscana Sci. Natur. 17, 95—103.

Cantú-Chapa A. 1967: El límite Jurásico—Cretácico en Mazatepec,

Puebla. Inst. Mex. Petrol., Technologia Explor., Sec. Geol.,
Monogr. 1, 3—24.

131

TAXONOMY OF UPPER TITHONIAN HIMALAYITID AMMONITES FROM LE CHOUET

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

Cantú-Chapa A. 1968: Sobre una asociacion Proniceras—Duran-

gites—“Hildoglochiceras” del Noreste de Mexico. Inst. Mex.
Petrol. 2, 19—26.

Cantú-Chapa A. 2006: New Upper Tithonian (Jurassic) Ammonites

of the Chinameca Formation in Southern Veracruz, Eastern
Mexico. J. Paleontology 80, 294—308.

Castillo A. del & Aguilera J.G. 1895: Fauna fósil de la Sierra de Ca-

torce, San Luis Potosi. Bol. Inst. Geol. México 1, 1—55.

Cecca F., Cresta S. & Santantonio M. 1983: Alcune ammoniti pro-

venienti dalla “Maiolica” dell’Appennino Centrale (Umbria,
Marche e Sabina). Boll. Serv. Geol. Ital. 103, 133—162.

Christ H.A. 1960: Beiträge zur Stratigraphie and Paläontologie des

Malm von Westsizilien. Schweiz. Paläeont. Abh. 77, 1—44.

Cobiella-Reguera J.L. & Olóriz F. 2009: Oxfordian—Berriasian

stratigraphy of the North American paleomargin in western
Cuba: Constraints for the geological history of the proto-Carib-
bean and the early Gulf of Mexico. In: Bartolini C. & Roman
Ramos J.R. (Eds.): Petroleum systems in the southern Gulf of
Mexico. AAPG Memoir 90, 421—451.

Collignon M. 1960: Atlas des fossiles caractéristiques de Madagas-

car. Fascicule VI (Tithonique). Serv. Géol. Madagascar,
Tananarive, 134—175.

Davis R.A., Landman N.H., Dommergues J.-L., Marchand D. &

Bucher H. 1996: Mature modifications and sexual dimorphism in
ammonoids. In: Landman N.H., Tanabe K. & Davis R.A. (Eds.):
Ammonoid Paleobiology. Topics in Geobiology 13, 463—539.

Enay R. & Geyssant J.R. 1975: Faunes tithoniques des chaînes bé-

tiques (Espagne méridionale). Mém. Bur. Rech. Géol. Min. 86,
39—55.

Enay R., Boughdiri M. & Le Hégarat G. 1998a: Toucasiella gen.

nov., Himalayitidae (Ammonitina) nouveau du Tithonien
supérieur: origine des Durangites. C.R. Acad. Sci. Paris, Sér.
2a, Sciences de la Terre et des Planètes 327, 471—477.

Enay R., Boughdiri M. & Le Hégarat G. 1998b: Durangites, Prota-

canthodiscus  (Ammonitina)  et  formes  voisines  du  Tithonien
supérieur—Berriasien  dans  la  Téthys  méditerranéenne  (SE
France,  Espagne,  Algérie  et  Tunisie).  C.R.  Acad.  Sci.  Paris,
Sér. 2a, Sciences de la Terre et des Planètes 327, 425—430.

Enay R., Boughdiri M. & Le Hégarat G. 1998c: Kilianites gen.

nov., Himalayitidae (Ammonitina) nouveau du Berriasian de la
région de Cabra (province de Cordoba, SE Espagne): descen-
dance de Protacanthodiscus. C.R. Acad. Sci. Paris, Sér. 2a,
Sciences de la terre et des planètes 327, 549—554.

Enay R., Martin C., Monod O. & Thieuloy J.-P. 1971: Jurassique

supérieur à Ammonites (Kimméridgien—Tithonique) dans
l’autochtone du Taurus de Beysehir, Turquie meridionale. Ann.
Inst. Geol. Publ. Hung. 54, 397—422.

Fischer P. 1882: Manuel de Conchyliologie et de Paléontologique

conchyliologique ou Histoire naturelle des Mollusques vivants
et fossiles: Fascicule IV. Masson, Paris, 305—416.

Fözy I. & Scherzinger A. 2013: Systematic descriptions of Titho-

nian  ammonites  of  the  Gerecse  Mountains.  In:  Fözy  I.  (Ed.):
Late  Jurassic—Early  Cretaceous  fauna,  biostratigraphy,  facies
and  deformation  history  of  the  carbonate  formations  in  the
Gerecse and Pilis mountains (Transdanubian Range, Hungary).
GeoLitera, Szeged, 207—292.

Geyssant J.R. 1997: Tithonien. In: Cariou E. & Hantzpergue P.

(Eds): Biostratigraphie du Jurassique ouest européen et médi-
terranéen: zonations parallèles et distribution des invertébrés et
microfossiles. Elf Aquitaine édition, Pau, 97—102.

Hoedemaeker P.J. & Bulot L.G. 1990: Preliminary ammonite zona-

tion for the Lower Cretaceous of the Mediterranean region.
Géol. Alp. 66, 123—127.

Imlay R.W. 1939: Upper Jurassic ammonites from Mexico. Geol.

Soc. Amer. Bull. 50, 1—78.

Imlay R.W. 1942: Late Jurassic fossils from Cuba and their eco-

nomic significance. Geol. Soc. Amer. Bull. 53, 1417—1478.

Imlay R.W. & Jones D.L. 1970: Ammonites from the Buchia zones

in northwestern California and southwestern Oregon. Geol.
Surv. Profess. Pap. 647-B, B1—B59.

Ivanov M., Stoykova K. & Idakieva V. 2010: New biostratigraphic

data on the Upper Tithonian and Lower Berriasian in the
Krayshte area (Southwestern Bulgaria). Ann. Univ. Sofia “St.
Kliment Ohridski”, Livre 1, Géol. 102, 21—42.

Khimshiashvili N.G. 1989: The Berriasellidae of Abkhazia. The

Tithonian fauna of mount Lakorizi-Tau (basin of Bzibi river).
Metsniereba, Tbilisi, 1—87 (in Russian).

Kilian W. 1889: Etudes paléontologiques sur les terrains secon-

daires et tertiaires de l’Andalousie. Mém. Acad. Sci. Inst.
France 30, 580—733.

Klein J. 2005: Lower Cretaceous Ammonites I. Perisphinctaceae 1.

Himalayitidae, Olcostephanidae, Holcodiscidae, Neocomitidae,
Oosterellidae. In: Riegraf W. (Ed.): Fossilium catalogus I: Ani-
malia, pars 139. Backhuys Publishers, Leiden, 1—484.

Korn D., Ebbighausen V., Bockwinkel J. & Klug C. 2003: The

A-mode sutural ontogeny in prolecanitid Ammonoids. Palae-
ontology 46, 1123—1132.

Le Hégarat G. 1973: Le Berriasien du sud—est de la France. Doc.

Lab. Géol. Fac. Sci. Lyon 43, 1—576.

Leanza A.F. 1945: Amonites del Jurásico superior y del Cretácico in-

ferior de la Sierra Azul, en la parte meridional de la provincia de
Mendoza. Anal. Mus. La Plata, NS Paleont. 1, 1—99.

Leanza A.F. 1968: Anotaciones sobre los fósiles Jurásico—Cretáci-

cos de Patagonia austral (colección Feruglio) conservados en
la Universidad de Bologna. Acta Geol. Lilloana 9, 121—179.

Mazenot G. 1939: Les Palaeophoplitidae tithoniques et berriasiens

du sud est de la France. Mém. Soc. Géol. France (Nouvelle
Sér.) 18, Mémoire 41, 1—303.

Myczynski R. 1989: Ammonite biostratigraphy of the Tithonian of

western Cuba. Ann. Soc. Geol. Pol. 5, 43—125.

Myczynski R. 1999: Some ammonite genera from the Tithonian of

western Cuba and their palaeobiogeographic importance. Stud.
Geol. Pol. 114, 91—112.

Myczynski R. & Pszczółkowski A. 1994: Tithonian stratigraphy

and microfacies in the Sierra del Rosario, western Cuba. Stud.
Geol. Pol. 105, 7—38.

Olóriz F., Villaseñor A.B., Gonzalez-Arreola C. & Westermann

G.E.G. 1999: Ammonite biostratigraphy and correlations in the
Upper Jurassic lowermost and correlations in the Upper Juras-
sic lowermost Mexico (Sierra de Catorce, San Luis Potosí). In:
Olóriz F. & Rodriguez-Tovar F.J. (Eds.): Advancing research
on living and fossil Cephalopods. Kluwer Academic/Plenum
Publishers, New York, 463—492.

Patrulius D. & Avram E. 1976: Les céphalopodes des Couches de

Carhaga (Tithonique supérieur—Barrémien inférieur). Mém.
Inst. Géol. Géophys. 24, 153—201.

Pervinquière L. 1907: Étude de paléontologie tunisienne. I. Cépha-

lopodes des terrains secondaires. Direction générale des
Travaux publics. Carte géologique de la Tunisie. De Rudeval,
Paris, 1—438.

Retowski O. 1893: Die tithonischen Ablagerungen von Theodosia.

Bull. Soc. Natur. Moscou 7, 206—301.

Rivera R. 1951: La fauna de los estratos de Puente Inga, Lima. Bol.

Soc. Geol. Peru 22, 5—53.

Roman F. 1936: Le Tithonique du massif du Djurdjura (province

d’Alger). Matériaux pour la Carte Géologique de l’Algérie,
Paléontologie 7, 1—43.

Roman F. 1938: Les ammonites jurassiques et crétacées. Essai de

genera. Masson, Paris, 1—554.

Sapunov I.G. 1979: Les fossiles de Bulgarie. III. 3. Jurassique

supérieur, Ammonoidea. Ed. Acad. Bulgar. Sci., 1—263.

Sarti C. 1988: Biostratigraphic subdivision for the Upper Jurassic of

132

FRAU, BULOT and WIMBLEDON

GEOL

EOL

EOLOGICA CARPA

OGICA CARPA

OGICA CARPATHICA

THICA

THICA, 2015, 66, 2, 117—132

Venetian Alps (Northern Italy) on the base of ammonites. 2

International Symposium on Jurassic Stratigraphy, Lisboa,
459—476.

Sarti C. 1995: Ptychophylloceras bisulcatum (Ammonoidea): nuova

specie di Phylloceratidae nel Titoniano del “Trento Plateau”
(Alpi meridionali, Italia). Mem. Sci. Geol. Univ. Padova 47,
245—251.

Sey I.I. & Kalacheva E.D. 1983: On invasions of Tethyan ammo-

nites in Boreal Late Jurassic basins of the East of USSR. In:
Zakharov V.A. & Nalnyaeva T.I. (Eds.): Mesozoic of the Soviet
Arctic. Trudy Inst. Geol. Geofiz. 555, 61—72.

Shome S. & Bardhan S. 2009: A new Late Tithonian ammonite as-

semblage from Kutch, Western India. J. Palaeont. Soc. India
54, 1—18.

Spath L.F. 1923: Appendix: On ammonites from New Zealand. In:

Trechmann C.T. (Ed.): The Jurassic rocks of New Zealand.
Quart. J. Geol. Soc. London 79, 286—308.

Spath L.F. 1925: Ammonites and aptychi. The collection of fossils

and rocks from Somaliland. Monographs Geological Depart-
ment of the Hunterian Museum 1, 111—164.

Spath L.F. 1931: Revision of the Jurassic cephalopod fauna of

Kachh (Cutch). Part IV. Palaeontologia Indica 9, 1—945.

Steinmann G. 1890: Cephalopoda. In: Steinmann G. & Döderlein L.

(Eds.): Elemente der Paläontologie. Engelmann, Leipzig,
344—475.

Steuer A. 1897: Argentinische Jura-Ablagerungen. Ein Beitrag zur

Kenntnis der Geologie und Paläontologie der argentinischen
Anden. Palaeont. Abh. 7 (N.F. 3), 129—222.

Szives O. & Fözy I. 2013: Systematic descriptions of Early Creta-

ceous ammonites of the carbonate formations of the Gerecse
Mountains, Hungary. In: Fözy I. (Ed.): Late Jurassic—Early Cre-
taceous fauna, biostratigraphy, facies and deformation history of
the carbonate formations in the Gerecse and Pilis mountains
(Transdanubian Range, Hungary). GeoLitera, Szeged, 293—342.

Tavera Benitez J.M. 1985: Les ammonites del Tithonico superior—

Berriasense de la Zona Subbetica (Cordilleras Beticas). Tesis
Doctoral. Universidad de Granada, 1—381.

Verma H.M. & Westermann G.E.G. 1973: The Tithonian (Jurassic)

ammonite fauna and stratigraphy of Sierra Catorce, San Luis
Potosí, México. Bull. Amer. Paleont. 63, 108—137.

Wimbledon W.A.P., Reháková D., Pszczółkowski A., Cassellato

C.E., Halásová E., Frau C., Bulot L.G., Grabowski J., Sobieñ
K., Pruner P., Schnabl P., Čížková K. & Tchoumatchenco P.
2013: A preliminary account of the bio- and magnetostrati-
graphy of the upper Tithonian—lower Berriasian interval at Le
Chouet, Drôme (SE France). Geol. Carpathica 64, 437—460.