Shazella Collins & Williams, 2005

Guinot, Danièle, Vega, Francisco J. & Van Bakel, Barry W. M., 2008, Cenomanocarcinidae n. fam., a new Cretaceous podotreme family (Crustacea, Decapoda, Brachyura, Raninoidia), with comments on related families, Geodiversitas 30 (4), pp. 681-719 : 681-719

Genus Shazella Collins & Williams, 2005

Shazella Collins & Williams, 2005: 33 , fig. 1.

TYPE SPECIES. — Shazella abbotsensis Collins & Williams, 2005 , Turonian of southern England.

Remarks

Shazella , included in the Necrocarcinidae by Collins & Williams (2005), does not belong to the Cenomanocarcinidae n. fam. because the carapace is devoid of the characteristic tuberculate ridges and is traversed by a deep cervical groove. Collins & Williams (2005: 34) concluded that Shazella differed from all other Necrocarcinidae by “the virtual absence of anterolateral spines, the marked constriction behind the orbitofrontal margin and the absence of median and lateral dorsal ridges”. Shazella is very close to Paranecrocarcinus , and better-preserved material is needed to verify the status and relationship of these two genera.

REMARKS ON ORITHOPSIS TRICARINATA ( BELL, 1863) AND ON THE FAMILY ORITHOPSIDAE SCHWEITZER, FELDMANN, FAM, HESSIN, HETRICK, NYBORG & ROSS, 2003

The type species of Orithopsis Carter, 1872 is not N. tricarinatus as indicated by Förster (1968: 177, 179; see also 1970: 141) but O. bonneyi Carter, 1872 by monotypy (see Glaessner 1969: R492, R627). However, as N. tricarinatus is the senior synonym of O. bonneyi (a hypothesis already put forward by Woodward 1877), the correct combination for the taxon is O. tricarinata (see Förster 1970: 141; Larghi & Garassino 2000: 54; Collins 2002: 85). Because a generic name that ends in a Greek word transliterated into Latin, i.e. ending in - opsis, is feminine ( ICZN 1999: Art. 30.1.2), the gender Orithopsis (derived from Orithyia from Greek mythology + the suffix - opsis) is feminine, hence O. tricarinata .

Schweitzer & Feldmann (2000: 246, fig.1) includ- ed Orithopsis in the Necrocarcinidae while Schweitzer et al. (2003a: 33, 39) excluded N. tricarinatus from Necrocarcinus listed in their table 3 and established the family Orithopsidae with Orithopsis as type genus. According to Schweitzer et al. (2003a) the

family Orithopsidae contains six genera: Orithopsis ,

Guinot D. et al.

Goniochele Bell, 1858 , Cherpiocarcinus Marangon & De Angeli, 1997 , Silvacarcinus Collins & Smith, 1993 , Marycarcinus Schweitzer, Feldmann, Fam, Hessin, Hetrick, Nyborg & Ross, 2003 , and Paradoxicarcinus Schweitzer, Feldmann, Fam, Hessin, Hetrick, Nyborg & Ross, 2003 . Like Glaessner (1969: R492, fig. 304.3), who referred Orithopsis to the Dorippidae, Schweitzer et al. (2003a) associated the Orithopsidae with the Dorippoidea, next to the Necrocarcinidae and Dorippidae .

In the diagnosis of the family Orithopsidae by Schweitzer et al. (2003a: 39), as well as in the congruent summary by Števčić (2005: 120), there is no mention of the venter or legs. Schweitzer et al. (2003a: 39, see also p. 32) indicate that Glaessner (1969) was “apparently based upon […] presence of female sternal gonopores”, but such a statement by Glaessner (1969) was likely only by inference to assignment to the Dorippoidea. As far as we know, with the exception of that of Silvacarcinus laurae Collins & Smith, 1993 , an orithopsid vulva has never been described nor figured. We have examined the original material of this species but no vulvae were found, so the eubrachyuran condition is not ascertained. It has also proved that the isolated sternum ( Collins & Smith 1993: pl. 2, fig. 3) is different from the sternum associated with the carapace of the male holotype of S. laurae ( Collins & Smith 1993: pl. 2, fig. 2) and does not belong to S. laurae . Preliminary data demonstrate that Silvacarcinus should be excluded from the Orithopsidae .

Necrocarcinus tricarinatus Bell, 1863 ( Bell 1863: 21, pl. 4, figs 9-11; see Beurlen 1958: fig.1b), regard- ed as a species of Orithopsis by Förster (1968: 177, 179), considered for a long time to be a Necrocarcinus ( Carter 1898: 28, 29; Glaessner 1969: R627, addenda:fig.304.3; Wright & Collins 1972: 66, pl.12, figs 3-6, pl. 13, figs 1-3; Bishop & Williams 1991: 458; Feldmann et al. 1993: 37; Fraaye 1994: 264, fig. 1; Fraaije 2002: 916; Collins & Jakobsen 1995: 39; Collins 2002: 85; Ilyin 2005: 201, pl. 9, fig. 5), was excluded from Necrocarcinus (see Woodward 1877) and again placed in Orithopsis by Larghi & Garassino (2000: 54).

Orithopsis tricarinata , a large-sized and thin-shelled species, is known principally by the photograph

published by Wright & Collins (1972: pl. 12, fig. 3, as Necrocarcinus tricarinatus ) which shows the carapace of the holotype of O. bonneyi from the upper Greensand (upper Albian) of Lyme Regis. Additional photographs in Wright & Collins (1972: pl. 12, figs 4-6, pl. 13, figs 1-3) illustrate other specimens. It should be noted that the diagrammatic figure of Orithopsis by Schweitzer & Feldmann (2000: 246, fig. 1) is not accurate enough, whereas a new “line drawing of Orithopsis Carter, 1872 ” ( Schweitzer et al. 2003a: fig. 13.5) does not represent Carter’s drawing (1872: pl. 13, fig. 1) of O. bonneyi nor that by Lőrenthey (1929: fig. 20a) but approximates the photograph of Wright & Collins (1972: pl. 12, fig. 3). Wright & Collins (1972) are specific in their caption: “unretouched photograph of specimen further prepared since the original illustration”.This explains why Carter (1872: pl. 13, fig. 1) incorrectly represented a front armed with four strong, unequal spines instead of the long, projected and bifid rostrum bordered by oblique spines characteristic of Orithopsis tricarinata . It is the same “prepared” specimen, i.e. the holotype of O. bonneyi , which is illustrated here ( Fig. 9E ).

Anyway, Orithopsis tricarinata has remained an insufficiently known species and, moreover, lacks preserved ventral structures, except for the trituberculate (?male) abdominal segments described by Wright & Collins (1972: 68). The long, slightly bifid and sulcate rostrum, the anterolateral margin and the front armed with numerous sharp spines, the medially interrupted cervical groove do not match the Cenomanocarcinidae n. fam. nor Necrocarcinidae emend. We have examined a specimen from the Cambridge Greensand (KBIN collections) which has a partially preserved sternum ( Fig. 9F ). Anterior sternites show as a small plate, separated by a distinct groove from sternite 4; sternite 4 is long; sternite 5 is incompletely preserved; the rather long and deep sterno-abdominal cavity reaches the level of sternite 3. A non-eubrachyuran condition is suspected.

The monotypical Orithopsis is known to range from the upper Aptian to Cenomanian andTuronian in many countries, from England, Spain, Bohemia ( Larghi & Garassino 2000: 54; Ilyin 2005).

The differences between Orithopsis and Necro-

carcinus are:carapace polygonal and flattened (versus rounded or ovate and vaulted in Necrocarcinus ), dorsal carapace ornament of tubercles and grooves weakly developed (better developed in Necrocarcinus ), rostral and orbital spines markedly developed (weak in Necrocarcinus ). The numerous differences between Orithopsis and Cenomanocarcinus concern principally the frontal, orbital and anterolateral borders (the epibranchial spine is much more developed in Cenomanocarcinus ); the posterolateral border, unarmed in Orithopsis (with tubercles or two marked teeth in Cenomanocarcinus ); the dorsal surface not ridged and showing a deep cervical groove in Orithopsis (tricarinate and with a faint cervical groove in Cenomanocarcinus ).

By including in the same family Orithopsis and Cherpiocarcinus (type species C. rostratus Marangon & De Angeli, 1997: 100 , fig. 2, pl. 1; see also De Angeli & Marangon 2003: 101, fig.1.1), from the Oligocene of northwest Italy, Schweitzer et al. (2003a: 39, 40) recognised their affinities. The numerous, aligned frontal spines of C. rostratus appear different, and relationships of Cherpiocarcinus with the Dorippoidea are problematic.

Necrocarcinus angelicus Fraaije, 2002 ( Fraaije 2002: 914, figs 1.1, 2), upper Maastrichtian of the Netherlands, was noted by Fraaije (2002: 916) to be closely related to O. tricarinata , and it might be transferred to Orithopsis as O. angelica .

Paradoxicarcinus Schweitzer, Feldmann, Fam, Hessin, Hetrick, Nyborg & Ross, 2003 (type species: P. nimonoides Schweitzer, Feldmann, Fam, Hessin, Hetrick, Nyborg & Ross, 2003: 43 , fig. 14) was included in the Orithopsidae by Schweitzer et al. (2003a: 39, 42). Paradoxicarcinus nimonoides , from the Santonian of Vancouver Island, British Columbia, Canada, is armed with orbital and anterolateral spines. The holotype figured by Schweitzer et al. (2003a: fig. 14.3) shows a fully preserved spiniform ornament of the frontal and anterolateral margins, including a long epibranchial spine (“incredible preservation” according to the authors). These spines are thicker than those shown in the reconstruction (2003a: fig. 14.2); in the paratype (2003a: fig. 14.1) all spines are broken. The broad orbits of P. nimonoides recall the enormous ones of “ N.” siouxensis (see under this name) which species

differs by having three tuberculate longitudinal ridges

Cenomanocarcinidae n. fam. ( Crustacea, Decapoda ) from Cretaceous

on dorsal carapace and lacking the deep cervical groove present in Paradoxicarcinus .

In P. nimonoides the development of regions on the dorsal carapace delimited by marked grooves and the absence of strong longitudinal branchial and epibranchial ridges are distinct from cenomanocarcinids. The carapace shape, the long rostral and orbital spines, the broader front, the type of dorsal ornamentation are not necrocarcinid features either. The dorsal surface is somewhat similar to that of “ Necrocarcinus ” renfroae which has an incomplete carapace without any spines ( Fig. 8B, D ) (see un- der this name).

Contrary to Orithopsis which is known solely from carapaces and a fragmentary anterior sternum, Goniochele (type species: G. angulata Bell, 1858 ) is documented by both male and female abdomens of G. angulata ( Bell 1858: 27, pl. 4, figs 8, 9; Carter 1898: 23, pl. 1, fig. 6) and the thoracic sterna of G. angulata and G. madseni Collins & Jakobsen, 2004 ( Carter 1898: 23; Collins & Jakobsen 2004: pl. 3, figs 2a, 4a). The dorsal position of both P4 and P 5 in G. angulata is evident from the disposition of their coxae in a figure in Bell (1858: pl. 4, fig. 5), which could ultimately support the attribution of Goniochele to the Dorippoidea. Known by several certain fossil records, the dorippoids are among the most primitive heterotreme crabs, and the morphology of Recent members attests to a long evolutionary history (Guinot, Tavares & Castro in study).

Figures

FIG. 9.— A, “Necrocarcinus” senonensis Schlüter in von der Marck & Schlüter 1868,middle Danian,Denmark,Fakse quarry,reconstructed photograph of the carapace (Collins & Jakobsen 1995: pl. 10, fig. 11), with two strong lateral spines; B, D, Camarocarcinus quinquetuberculatus Collins & Wienberg Rasmussen,1992, holotype, probably male (cast, MGUH 21609;courtesy of S. L. Jakobsen), dorsal and ventral views; C, Cretacoranina cf. dichrous (Stenzel, 1945) (Palaeocorystidae), middle Cenomanian, Karai Formation, between Odiyam and Kunnam,Tamil Nadu, India,leg.A.S.Gale, 1999 (OUM KY.2861), thoracic sternum, see individualised sternite 3, lateral expansions of sternite 4,and deep sutures 4/5; E, F, Orithopsis tricarinata (Bell,1863);E, upper Albian,Upper Greensand,England,Cowstones,holotype of O. bonneyi Carter, 1872, “unretouched photograph of specimen prepared since the original illustration” (Wright & Collins 1972: pl. 12, fig.3) (SM B58557);F, upper Albian,Cambridge Greensand (KBIN,Van Straelen Collection,unnumbered),thoracic sternum,with preserved

FIG. 8. — A-D, “Necrocarcinus” renfroae Stenzel, 1945, Early Cretaceous, upper Albian, Texas, Pawpaw Formation; A, B, paratype (BEG-21094-A3), frontal and dorsal views; C, D, holotype (BEG-21093-A3), frontal and dorsal views; E, F, Necrocarcinus labeschii (Deslongchamps, 1835), Albian, Calais, Escalles, northwest France (B. van Bakel Colln), left chela and carapace. Scale