Denticupachydomella Yuan, 2009

Tarnac, Anaëlle, Forel, Marie-Béatrice, Nestell, Galina, Nestell, Merlynd & Crasquin, Sylvie, 2021, Middle Permian ostracods (Crustacea) from the Guadalupe Mountains, West Texas, USA, European Journal of Taxonomy 770, pp. 1-60 : 44-45

Genus Denticupachydomella Yuan in Yuan et al., 2009

Type species

Denticupachydomella spinosa Yuan in Yuan et al., 2009 by original designation.

Original diagnosis

“A new Pachydomellidae genus with left valve having straight dorsal border, two horny dorsal spines erecting at the anterior cardinal angle, one stronger spine at the posterior cardinal angle, three denticles along dorsal border, one posteroventral spine and pustulous lateral surface.” (from Yuan et al. 2009: 392–393).

Emended diagnosis

A new genus with a relatively massive postero-ventral spine, spines of various morphology and strength developed along the dorsal margin of the left valve and surface pustulose.

Assigned species

The following species are herein re-assigned to the genus Denticupachydomella :

Microcheilinella? multinodosa Forel in Crasquin et al., 2010 from the Changhsingian, Late Permian of the Meishan section, Zhejiang Province, China ( Crasquin et al. 2010);

Microcheilinella sp. D in Zazzali (2016: 208–209, pl. 14f–g, unpublished material, PhD thesis), Late Capitanian, Middle Permian, Penglaitan section, Guangxi, South China ( Fig. 11R–S ).

Remarks

The thorough comparison of ornate Microcheilinellidae revealed that all the above-mentioned species share postero-ventral spines on both valves and spines/nodules/pustules along the dorsal margin and over the lateral surface. Conversely, the two horny dorsal spines and the three denticles along the dorsal border originally described by Yuan et al. (2009) as of generic significance to the newly erected genus Denticupachydomella rather appear as variations of the morphology and strength of the spines, thus being of specific significance. The diagnosis of Denticupachydomella Yuan in Yuan et al., 2009 is here emended to clarify this issue of generic versus specific characters.

Figures

Fig. 11 (next page). SEM micrographs of ostracods from the Middle Permian (Roadian, Quarry section, samples GM1, GM2 and GM4; Capitanian, MKCS1 section, samples 4 (GM5) and 2 (GM6)) of the Guadalupe Mountains (West Texas, USA), except R and S from the late Capitanian, Middle Permian, Penglaitan section, Guangxi, South China (Zazzali 2016, unpublished PhD thesis). All specimens from A–Q are temporarily housed in the collections of the Muséum national d’histoire naturelle, Paris, France (MNHN), specimens R and S are housed in the collections of the Sorbonne University, Paris, France. A–B. Ceratobairdia cf. ventrocostata Wang, 1978. A. External view of a left valve, sample 4 (GM5) (MNHN.F.F63454). B. External view of a left valve, sample 2 (GM6) (MNHN.F.F63455). – C–G. Ceratobairdia pratti Forel sp. nov. C. Holotype, right lateral view of a carapace, sample GM1 (MNHN.F.F63456). D. Paratype, external view of a left valve, sample GM1 (MNHN.F.F63457). E. External view of a left valve, sample GM1 (MNHN.F.F63458). F. External view of a left valve, sample GM1 (MNHN.F.F63459). G. External view of a left valve, sample GM1 (MNHN.F.F63460). – H–I. Petasobairdia campbelli Chitnarin in Chitnarin et al., 2017. H. External view of a left valve, sample GM2 (MNHN.F.F63461). I. External view of a left valve, sample GM4 (MNHN.F.F63462). – J. Petasobairdia cf. bicornuta Chen in Chen & Shi, 1982, right lateral view of a carapace, sample 4 (GM5) (MNHN.F.F63463). – K. Petasobairdia? sp., external view of a right valve, sample 4 (GM5) (MNHN.F.F63464). – L. Microcheilinella postspinosa Chen, 1958, right lateral view of a carapace, sample 2 (GM6) (MNHN.F.F63465). – M. Microcheilinella sp. 15 in Zazzali et al. (2015), right lateral view of a carapace, sample 4 (GM5) (MNHN.F.F63466). – N–O. Microcheilinella sp. N. Right lateral view of a carapace, sample 2 (GM6) (MNHN.F.F63467). O. Right lateral view of a carapace, sample 4 (GM5) (MNHN.F.F63468). – P–Q. Denticupachydomella bellcanyonensis Forel sp. nov. P. Holotype, right lateral view of a carapace, sample 4 (GM5) (MNHN.F.F63469). Q. Paratype, external left of a right valve, sample 2 (GM6) (MNHN.F.F63470). – R–S. Microcheilinella sp. D in Zazzali (2016). R. Dorsal view of a carapace (P6M 3778). S. Right lateral view of a carapace (P6M 3779). Scale bars: 100 µm.