Identification key for the Brazilian species and subspecies of the family Ilyocryptidae (Crustacea, Branchiopoda, Anomopoda) Author Sousa, Francisco Diogo Rocha Author Elmoor-Loureiro, Lourdes Maria Abdu text Papéis Avulsos de Zoologia 2019 2019-05-15 59 1 8 journal article 6037 10.11606/1807-0205/2019.59.23 9209b35f-437f-4238-b4a6-c4d00a2aa10b 1807-0205 4613798 Ilyocryptus spinifer Herrick, 1882 Body sub-ovoid or triangular shaped, dorsal keel well developed, molting incomplete; setae on the posterior margin of valves with inflated base and armed with a long and sharp spine, setulae present; posteriormost setae on the valves armed with setulae. Head triangular shaped, fornices prominent and with a projection in the region of mandibular articulation; spine on the second segment of endopodite of antenna longer than midlength of the third segment. Postabdomen large, preanal part shorter than postanal; marginal denticles of preanal part with regular morphology, relatively long; 16-14 marginal spines of similar length; 3-5 long lateral setae about 4-5 times longer than marginal spines; a long “gap” between proximalmost lateral seta and anal margin; basal spines on the postabdominal claw of different length. Comments: This is a cosmopolitan species. It is the most commonly found Ilyocryptidae taxon in Brazilian continental waters ( Fig. 3G ). The morphological variation exhibited by this species was described by Elmoor-Loureiro (1997) , Kotov & Williams (2000) , Kotov & Dumont (2000) , and Kotov & Štifter, 2006 .