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Pustulina colossea n. sp. (Fig. 9G, H) TYPE MATERIAL. — Holotype MNHN.F. A57459 (Leroy coll.). TYPE LOCALITY. — Castellane, Alpes-de-Haute-Provence department, Provence-Alpes-Côte d’Azur region, southeastern France. TYPE AGE. — Hauterivian, Early Cretaceous. ETYMOLOGY. — The specific epithet refers to the massive size and appearance of the carapace for a representative of Pustulina. DESCRIPTION Subcylindrical carapace (holotype: CL = c. 50 mm with incomplete branchial region, CH = 29 mm); rostrum not preserved; cephalic region with dorsal line strongly inclined downward; strongly inflated cardiac, hepatic and branchial regions; wide, deep cervical groove, subvertical, slightly sinuous at level of gastro-orbital groove, narrowing above its junction to hepatic groove, joined to dorsal margin and to antennal groove; narrow, shallow antennal groove, strongly curved towards anterior margin; wide, deep gastro-orbital groove, originating as a median inflexion of cervical groove, with two divergent branches delimiting two inflated gastro-orbital lobes; wide postcervical groove, strongly inclined in dorsal branchial region and arcuate before joining hepatic groove, forming a notch in upper hepatic region; deep, concave hepatic groove, joined to cervical groove; inferior groove joined to hepatic groove; shallow, straight cardiac groove, rising from postcervical groove, slightly inclined forward, joined to dorsal margin; carapace entirely covered with rounded tubercles, coarser and more widely spaced forward postcervical groove, thinner and closer in branchial and pterygostomial regions; row of coarse tubercles parallel to intercalated plate; cephalic region with convex antennal row of tubercles and distal antennal spine. DISCUSSION Pustulina colossea n. sp. is assigned to Pustulina based on its typical carapace groove pattern: long gastro-orbital groove with two branches, postcervical groove joined to hepatic groove, concave hepatic groove and cardiac groove. Pustulina colossea n. sp. differs from Pustulina tuberculata and Pustulina spinulata by the cephalic region with dorsal margin strongly inclined downward (straight in the latter), its postcervical groove curved in dorsal branchial region (straight in the latter), its prominent upper gastro-orbital lobe (flat in the latter), and its heterogeneous ornamentation (homogeneous in the latter). The differences between P. colossea n. sp. and Pustulina occitana n. sp. are described in the discussion about P. occitana n. sp. Among Pustulina species, P. colossea n. sp. is the only one showing a curved postcervical groove and a raised upper gastro-orbital lobe. Furthermore, some morphological characters of P. colossea n. sp., in particular the width of cervical and gastro-orbital grooves and the massive appearance of the carapace, are also encountered in Enoploclytia. |
