Ischiomysis proincisa sp. nov.; paratypes adult ♀ (BL 4.3 mm, A–D) and adult ♂ (BL 4.5 mm, E–M); A. Right mandible with palpus, caudal; B, C. Masticatory parts of right (B) and left (C) mandibles, caudal; D. Maxillary palp, rostral; E. Thoracic sternites 1–8 with penes, ventral; F. Thoracic endopod 1 with part of coxa, caudal; G. Detail of (F) showing dactylus 1 with claw, setae omitted; H. Secondary detail of (F) showing claw 1; I. Thoracic endopod 2, rostral; J. Detail of (I) showing dactylus 2 with claw, setae omitted; K. Thoracic endopod 4 with basis (sympod), rostral; L, M. Details of (K) showing modified setae of the carpus (L) and the propodus (M).