Argentodromas, Díaz & Martens, 2018

Díaz, Analia & Martens, Koen, 2018, Psammoecus simonis Grouvelle 1892, Zoological Studies 57 (10), pp. 1-13 : 2-4

Argentodromas gen. nov. Díaz and Martens

urn:lsid:zoobank.org:pub:F251BB95-49E2-4000-A3D6-D18DB76B3ECF

Etymology: The first part of the genus name, “ Argento ”, refers to the country Argentina, the second part refers to the genus Notodromas to which the new genus is closely related.

Type species: Argentodromas bellanella gen. nov., sp. nov. (designated here).

Diagnosis: Surface of carapace covered with polygonal elevations and many pores with setae. Large part of ventral surface set with 3-4 rows of rounded elevations and bordered with an elevated outer list. Eye tubercles weakly developed. Prehensile palps moderately asymmetrical and both with first segments elongated. Posterior seta of CR longer than terminal claws, anterior seta present. Hemipenis with elongated and rounded outer lobe and pronounced subrectangular lateral lobe.

Differential diagnosis within Notodromadinae : Argentodromas gen. nov. is closely related to Newnhamia , but differs in the shape and structure of the carapace. In Newnhamia the carapace is oval in shape in anterior view and the surface of valves is covered with polygonal elevations and rounded or pointed tubercles. The largest part of the ventral plate-like surface is set with 2-3 rows of rounded elevations and bordered by an elevated outer list. Newnhamia also has clearly pronounced eye tubercles and has a completely different structure of hemipenis (with rounded ms in the new genus). Argentodromas gen. nov. differs from Kennethia , the second Australian genus, because of the lack of the large dorsal expansion on the LV and of the very pronounced external ornamentation in both valves in the latter genus. Argentodromas gen. nov. differs from Notodromas (of which Gurayacypris is most likely a synonym) mainly in the ornamentation of the carapace (almost smooth in Notodromas ) and the eye tubercles that are less well-developed in the new genus, as well as in the more strongly asymmetrical prehensile palps and the different hemipenis shape in Notodromas (large main body and only one hook-like expansion - see Meisch 2000, Fig. 99L). Finally, Argentodromas gen. nov. differs from Centrocypris in the morphology of carapace and limbs, especially in the valve ornamentation (at least the type species of Centrocypris has a ventral row of strong spines along the ventral margin in both valves - see Martens et al. 2008, Fig. 1 ).

Figures

Fig. 1. Map showing the position of the sampled stream in the Misiones province, Argentina.