New species of Ilanga (Gastropoda: Trochoidea: Solariellidae) from the Indo-West Pacific Author Vilvens, Claude Author Williams, Suzanne T. text Zootaxa 2020 2020-02-12 4732 2 201 257 journal article 24073 10.11646/zootaxa.4732.2.1 7aff0d3b-eb60-43e7-ace6-caffff8c1d72 1175-5326 3663329 F3FE261C-0865-40A7-AAAA-63791DD836A5 Key 2: Key to Ilanga species of Indo-Pacific area studied in this work 1. subsutural axial pleats visible on second or third whorl........................................................ 2 - no obvious subsutural axial pleats on whorls.............................................................. 13 2 (1). umbilical rim rounded to weakly subangulate............................................................... 3 - umbilical rim angulate................................................................................. 6 3 (2). no axial threads inside umbilicus........................................................................ 4 - axial threads inside umbilicus........................................................................... 5 4 (3). conical shape with nearly flat whorls................................................... I. cosmia - conical to slightly cyrtoconoidal shape, convex whorls.................................. I. corrineae 5 (3) rather depressed spire, 4 Pi, very large umbilicus........................................... I. comes - rather elevated spire, 5 Pi, moderately large umbilicus.................................. I. dongshaensis 6 (2). always axial threads inside the umbilicus.................................................................. 7 - no axial threads always present inside the umbilicus.......................................................... 9 7 (6). ± 3 spiral cords around umbilicus, central base area reticulate............................... I. oxeia - usually one single spiral cord around the umbilicus.......................................................... 8 8 (7). rounded periphery without spiral cords.............................................. I. eurystoma - subangulate periphery, faint spiral cords on periphery.................................... I. harrytaylori 9 (6). depressed, lenticular................................................................................. 10 - at most moderately depressed........................................................................... 11 10 (9). strongly depressed, spiral cords around the umbilicus, up to 19 mm ............................. I. gotoi - a single spiral cord around the umbilicus.......................................... I. euryomphalos 11 (9). rather elevated spire............................................................ I. navakaensis - moderately depressed spire only........................................................................ 12 12 (11).5 Pi....................................................................... I. stephanophora - 4 Pi......................................................................... I.polygramma 13 (1). umbilical rim only weakly subangulate.................................................. I. fulgens - umbilical rim angulate or at least subangulate.............................................................. 14