Hoploparia pusilla Secretan 1964

Hoploparia pusilla Secrétan, 1964 (Fig. 17)

Hoploparia pusilla Secrétan, 1964: 109-112, pl. 10, figs 3, 4. — Aguirre Urreta 1989: 519, 526. — Karasawa & Hayakawa 2000: 141. — Tshudy & Sorhannus 2003: 708, 709. — Garassino et al. 2009: 89. — Schweitzer et al. 2010: 30.

HOLOTYPE. — MNHN.F. R 03904.

PARATYPES. — From the “Coupe de Berere”: 2 specimens (MNHN.F. R 03905, A31657, gisement 166). Menabe region, central Morondava Basin, Tulear Province.

TYPE LOCALITY. — Coupe de Berere (gisement 166), Belo-sur-Thsiribihina, Menabe region, central Morondava Basin, Tulear Province.

TYPE AGE. — Early Campanian.

ADDITIONAL MATERIAL EXAMINED. — 1 specimen (MNHN.F.A33390, Coupe de Berere, gisement 166). Belo-sur-Thsiribihina, Menabe region, central Morondava Basin, Tulear Province.

DIAGNOSIS. — Cephalothorax with deep cervical groove starting at mid-height and joining the antennal groove; deep postcervical groove joining the well-marked hepatic groove; branchiocardiac and inferior grooves absent; gastric region with small spine; antennal region with tuberculate antennal carina; rostrum dorsally flat, flanked by two smooth lateral carinae, one strong, welldeveloped basal spine.

DESCRIPTION

Cephalothorax subcylindrical (CL = c. 19 mm, CH = c. 10 mm); rostrum dorsally flat with smooth margins and flanked by two smooth lateral carinae; one strong, well-developed basal spine; ocular incision shallow, delimited ventrally by the antennal spine; gastric region not delimited by the cervical groove, bearing one small spine located in the centre of the ocular incision; antennal region well demarcated by the cervical and antennal grooves, bearing a single postantennal spine aligned with the tuberculate antennal carina distally prolonged by the antennal spine; deep cervical groove starting at mid-height and joining the antennal groove; postcervical groove deep, slightly inclined, intercepting dorsal margin at an angle of c. 70°, starting in the first posterior ⅓ of the dorsal margin and clearly joining the well-marked hepatic groove; pterygostomial region strongly inflated; posterior margin slightly sinuous with a thin marginal carina; ornament uniformly finely tuberculate.

Abdomen with subrectangular somites; somites 1 and 6 smaller than the others; somites 2-5 of uniform length; terga and pleurae uniformly tuberculate; pleurae with weak depression; telson subrectangular with two pairs of carinae converging distally, ornament similar to that of somites. Pereiopods fragmentary, only one propodus with carinate inner margin.

DISCUSSION

Upon re-examination of the Malagasy material studied by Secrétan (1964), we agree with her generic attribution and with the erection of a new species. As pointed out by Secrétan (1964) and confirmed by our new observations, H. pusilla differs from H. collignoni in having a deep postcervical groove joining an equally deep hepatic one. Moreover, there is a difference in stratigraphic age between the two species.