Stenodactylina granulifera ( Secrétan, 1964 )

Devillez, Julien & Charbonnier, Sylvain, 2021, Review of the Late Jurassic erymoid lobsters (Crustacea: Decapoda), Geodiversitas 43 (2), pp. 25-73 : 60-61

Stenodactylina granulifera ( Secrétan, 1964) ( Fig. 16 H-J)

Eryma granulifera Secrétan, 1964: 64 , pl. 1, fig. 1, pl. 3, fig.1. — Förster 1966: 125. — Garassino & Schweigert 2006: 8. — Feldmann & Titus 2006: 64. — Schweitzer et al. 2010: 24.

Eryma madagascariensis Secrétan, 1964: 61 , pl. 3, figs 2-3. — Förster 1966: 116, 125, 162. — Taylor 1979: 36. — Förster & Seyed-Emami 1982: 44. — Garassino & Schweigert 2006: 8. — Feldmann & Titus 2006: 64. — Schweitzer et al. 2010: 24.

Eryma cf. bedelta – Beurlen 1933: 89, fig. 1.

Stenodactylina granulifera – Devillez et al. 2016: 524, table 1.

TYPE MATERIAL. — Holotype MNHN.F.R03975. TYPE LOCALITY. — East of Antsalova , Maintirano region, Tulear province, Madagascar. TYPE AGE. — Kimmeridgian .

DESCRIPTION

Carapace

Sub-cylindrical carapace; fusiform intercalated plate; narrow post-orbital area; wide cephalic region; deep and wide cervical groove, strongly inclined, joined to dorsal margin and to antennal groove; deep and narrow antennal groove; short, shallow gastro-orbital groove, oblique, originating as a slight median inflexion of cervical groove; inferior gastro-orbital lobe slightly inflated; postcervical and branchiocardiac grooves subparallel; deep postcervical groove, strongly inclined and curved forward, joined to dorsal margin and interrupted in hepatic region; deep branchiocardiac groove, slightly curved forward, joined to dorsal margin and to hepatic groove; hepatic groove concavo-convex, joined to cervical groove; ω and χ areas slightly inflated; deep, wide inferior groove, joined to hepatic groove.

Pleon and uropods

Somites with subtriangular pleurites, with a longitudinal bulge on their basis.

Thoracic appendages

Elongated P2-P5 merus.

Ornamentation

Carapace densely covered by small tubercles preceded by depressions, the tubercles are coarser along the intercalated plate; pleonal somites densely covered by small rounded depressions; P2-P5 merus covered by small rounded and widely spaced depressions.

DISCUSSION

This species was described from a carapace firstly assigned to Eryma ( Secrétan 1964) . A second species, E. madagascariensis Secrétan, 1964 , based on a carapace connected to a fragment of pleon was also described ( Fig. 16J ). The review of the decapod crustaceans of Madagascar by Charbonnier et al. (2012a) concluded to the synonymy between Eryma granuliferum and E. madagascariensis because of their very close carapace groove pattern. Later, Devillez et al. (2016) assigned E. granuliferum to Stenodactylina because of the absence of junction between the postcervical and branchiocardiac grooves and the interruption of the postcervical groove in hepatic region. In addition to the carapace groove pattern, the slight inflation of ω and χ areas, and the ornamentation made of small tubercles preceded by depressions support the synonymy between S. granulifera and E. madagascariensis .

Both ω and χ areas are inflated in Stenodactylina granulifera , contrary to S. australis , S. delphinensis , S. deslongchampsi , S. shotoverigiganti n. sp., S. triglypta , and S. walkerae . S. granulifera is one of the species within the genus, with S. walkerae , to exhibit an inflated gastro-orbital lobe. Its thin ornamentation is also distinct from that of S. australis , S. granulifera , S. lagardettei , S. pseudoventrosa , S. shotoverigiganti n. sp., S. triglypta , and S. walkerae .

Figures

FIG. 16. — Stenodactylina insignis (Oppel,1862), Stenodactylina shotoverigiganti n. sp. and Stenodactylina granulifera (Secrétan,1964):A, holotype of S. insignis (Oxfordian, Haute-Saône, France); B, holotype MFN 2236 P1383/2 MB.A.1536 of Eryma anisodactylus Krause,1891 (Kimmeridgian, Holzen,Germany); C, specimen IRSNB without number of S. insignis (Kimmeridgian, La Rochelle, France); D-G, holotype NHMUK 24559 of S. shotoverigiganti n. sp. (Oxfordian, Shotover, United Kingdom):right lateral view (D), left lateral view (E), schema (F), dorsal view (G); H-J, holotype MNHN.F.R03975 of S. granulifera (Kimmeridgian,Antsalova, Madagascar): lateral view (H), schema (J); C, D, holotype MNHN.F.R03974 of Eryma madagascariensis Secrétan, 1964 (Kimmeridgian, Antsalova, Madagascar). Abbreviations:a, branchiocardiac groove;b, antennal groove; b1, hepatic groove; c, postcervical groove; d, gastro-orbital groove; e1e, cervical groove; i, inferior groove;ip, intercalated plate; χ, attachment site of adductor testis muscle;ω, attachment site of mandibular muscle.Photographs:A, L. Cazes;B-E, G,J. Devillez; H, J, C. Lemzaouda. Line drawings: J. Devillez. Scale bars: 1 cm.