Facetotecta, Grygier, 1985

Kolbasov, Gregory A., Grygier, Mark J., Ivanenko, Viatcheslav N. & Vagelli, Alejandro A., 2007, A New Species Of The Y-Larva Genus Hansenocaris Itô, 1985 (Crustacea: Thecostraca: Facetotecta) From Indonesia, With A Review Of Y-Cyprids And A Key To All Their Described Species, Raffles Bulletin of Zoology 55 (2), pp. 343-353 : 351-352

Key to the species of Facetotecta described from the cypris y stage

1. Abdomen two-segmented ................................ H. tentaculata

– Abdomen four-segmented .................................................... 2

2. Anterior end of head shield strongly produced, antennular hook absent .................................................................................... 3

– Anterior end of head shield round or slightly produced, antennular hook present ....................................................... 4

3. Anterior end of head shield sharp, six telsonic spines ........... ............................................................................ H. acutifrons

– Anterior end of head shield blunt, five telsonic spines .......... ................................................................................ H. rostrata

4. Head shield elongate, its posterior ends reaching abdomen, anterior end lacking papilliform protrusions ....................... 5

– Head shield short, its posterior ends not reaching abdomen, anterior end with ventral papilliform protrusions ................... ............................................................................. H. papillata

5. Antennular aesthetasc constricted at mid-length, posterior ends of head shield reaching telson ..................................... H. itoi

– Antennulary aesthetasc not constricted at mid-length, posterior ends of head shield not reaching telson .............................. 6

6. Entire surface of head shield covered by cuticular ridges, three telsonic spines ....................................................... H. pacifica

– Cuticular ridges absent in dorsal part of head shield, five telsonic spines ................................................................... H. furcifera