Planobranchia simplex (Remy, 1960) Schweitzer & Feldmann, 2010

Schweitzer, Carrie E. & Feldmann, Rodney M., 2010, New fossil decapod crustaceans from the Remy Collection, Muséum national d’Histoire naturelle, Paris, Geodiversitas 32 (3), pp. 399-415 : 408

publication ID	https://doi.org/10.5252/g2010n3a3
persistent identifier	https://treatment.plazi.org/id/815F8783-F96A-FFDA-D8E5-FAC7FC5EB2EA
treatment provided by	Felipe (2021-04-14 18:42:41, last updated by Plazi 2023-11-02 06:27:48)
scientific name	Planobranchia simplex
status	comb. nov.

Treatment

Planobranchia simplex View in CoL n. comb. (Remy in Gorodiski & Remy, 1959) ( Fig. 2A View FIG )

Micromaia simplex Remy View in CoL in Gorodiski & Remy, 1959: 317, fig. 2.

TYPE MATERIAL. — Holotype (carapace) by monotypy ( MNHN R03839, coll. Gorodiski). Casts of the type ( KSU D1097 ) are deposited in the Department of Geology , Kent State University.

TYPE LOCALITY. — N’Gueyène, western Senegal, Upper Lutetian ( Gorodiski & Remy 1959).

DISCUSSION

The description by Remy in Gorodiski & Remy (1959: 317) adequately describes the species and will not be repeated here. The genus Planobranchia n. gen. embraces two species that are quite similar to one another and confirm their affinities and their distinction from species of Micromaia as discussed above. Planobranchia simplex n. comb. has a broader, more inflated epibranchial and mesobranchial region than does the type species. Th e cardiac region of the Senegal specimen is narrower, about 21% maximum width, whereas the cardiac region of P.laevis n. comb. ( Fig. 2B View FIG ) is about 27% maximum width. The transverse ridge on the cardiac region of P.simplex n. comb. is more subtle than that of P.laevis n. comb., and the ridge on the latter species extends laterally to intersect the margin of the mesobranchial region. Finally, the metabranchial region on P. simplex n. comb. is irregularly elevated but smooth, whereas that surface on P. laevis n. comb. is also irregularly elevated but is covered with tiny pits or perforations. The frontal regions on both type specimens are broken, so that comparison is not possible.

Both species of Planobranchia n.gen. were collected from Eocene rocks in North and West Africa, on the south margin of the Tethyan seaway.Th e type species was collected near Cairo, Egypt ( Lőrenthey 1909). Species of Micromaia are known primarily from Italy, but also from other localities on the northern margin of the Tethys seaway.

References

GORODISKI A. & REMY J. - M. 1959. - Sur les decapodes eocenes du Senegal occidental. Bulletin de la Societe geologique de France 7 e serie 1 (3): 315 - 319, pl. 19 a.

LORENTHEY E. 1909. - Beitrage zur Tertiaren Dekapodenfauna Sardiniens. Mathematischen und Naturwissenschaftlichen Berichte aus Ungarn 24: 202 - 259, pls 1, 2 (Hungarian version published in 1907).

Figures

FIG. 2. — Fossil Brachyura from Monségur (Gironde, France): A, Planobranchia simplex (Remy, 1960) n. comb., cast of holotype, MNHN R03839,dorsal carapace;B,Planobranchia laevis (Lőrenthey,1909) n. comb.,cast of holotype,IMDASlf.Nr.25520/2005 (dorsal carapace); C, Branchioplax? ballingi Remy in Remy & Tessier, 1954, cast of holotype, MNHN R03793, fragmental dorsal carapace; D, Liocarcinus heintzi n. sp., holotype, R03778, dorsal carapace; E, F, Pleolobites erinaceous Remy, 1960, casts of holotype, MNHN R03782 (E), and MNHN R03781 (F). Scale bars: 1 cm.