Key to genera of Euchromadorinae 1 Spicules jointed···························································· Rhips – Spicules not jointed···························································· 2 2 Amphideal fovea with thickened walls looking like a double contour···································································· 3 – Amphideal fovea without thickened walls······················ 4 3 Gubernaculum without lateral pieces · Adeuchromadora – Gubernaculum with lateral pieces ················ Actinonema 4 Pharynx with posterior terminal bulb····························· 5 – Pharynx without posterior terminal bulb······················· 7 5 Gubernaculum without lateral pieces ············ Trochamus – Gubernaculum with lateral pieces ··································· 6 6 Precloacal cuticular elevation present ····· Portmacquaria – Precloacal cuticular elevation absent············ Steineridora 7 Gubernaculum without lateral pieces ········· Endeolophos – Gubernaculum with lateral pieces ··································· 8 8 Buccal cavity with rows of denticles ········· Euchromadora – Buccal cavity without denticles ········································ 9 9 Precloacal cuticular elevation present ··· Parapinnanema – Precloacal cuticular elevation absent····························· 10 10 Amphideal fovea oval ······································ Crestanema – Amphideal fovea either transverse slit-like or indistinct ··········································································· Graphonema

Published as part of Shimada, Daisuke, Tsujimoto, Megumu & Watanabe, Kentaro, 2019, A New Free-living Marine Nematode Species of the Genus Graphonema (Nematoda: Chromadorida: Chromadoridae) from Antarctica, pp. 61-67 in Species Diversity 24 (1) on page 62, DOI: 10.12782/specdiv.24.61, http://zenodo.org/record/4585216