On Argentodromas bellanella gen. nov. sp. nov. (Crustacea Ostracoda)from a Stream in Northeastern Argentina (South America)

摘要

gen. nov., sp. nov. is here described from streams in the province of Misiones,in northeastern Argentina. The new genus and species belong to the family Notodromadidae.Most species in the family have morphological adaptations to a hyponeustic mode of life:their carapaces have lip-like protrusions of the valve margins near the mouth and a flatplate-like expansion of the ventral part. The new genus can be distinguished from othergenera in the subfamily Notodromadinae based on valve ornamentation (surface of valvescovered with polygonal elevations and many pores with setae), the ventral plate-likeexpansion which is set with 3-4 rows of rounded elevations and bordered with an elevatedouter list, eye tubercles softly pronounced, and soft parts features (male prehensilepalps moderately asymmetrical and both with elongated first segments, posterior seta ofcaudal ramus longer than terminal claws and anterior seta present, hemipenis with roundedouter lobe and small rounded inner lobe). For comparative purposes, valves and carapacesof species in three other Notodromadinae genera ( , , ) are also illustrated andre-diagnosed.