A new species of Carinosquilla (Crustacea, Stomatopoda, Squillidae) from the Seychelles with a cladistic analysis of the genus Author Ahyong, Shane T. Marine Biodiversity and Biosecurity, National Institute of Water and Atmospheric Research, Private Bag 14901, Kilbirnie, Wellington (New Zealand) s. ahyong @ crustacea. net text Zoosystema 2006 28 2 307 314 journal article 10.5281/zenodo.5403198 1638-9387 5403198 RELATIONSHIPS IN CARINOSQUILLA Analysis of the dataset resulted in five most parsimonious trees (length 50, consistency index 0.73, retention index 0.83). The strict consensus is shown in Figure 2 . Jackknife proportions indicate a robust topology. Monophyly of Carinosquilla is strongly supported with a 100% jackknife proportion. Carinosquilla falls broadly into four groups. The first group comprises C. carita and C. multicarinata , and is the sister to all other species of the genus. It is united by the presence of transverse carinae on TS5 and long, straight, carinae flanking the posterior bifurcation of the carapace that reach the posterior margin of the carapace. The second group includes C. lirata , differing from other species of Carinosquilla in having a crenulate instead of spinose inner margin on the uropodal protopod. Manning (1995) placed C. lirata in a monotypic genus Keijia , chiefly on the basis of the suppression of the mandibular palp in contrast to the species of Carinosquilla known at the time. The position of C. lirata , nested within other species of the genus, corroborates Ahyong’s (2001) synonymy of Keijia with Carinosquilla . The third and fourth groups are united by having carinate eyestalks, numerous supplementary carinae on the sternum of AS 6 and tricarinate submedian carinae on AS 6. The third group comprising C. carinata , C. spinosa and C. redacta is united principally by the possession of bifurcate ocular scales. The fourth group comprises C. australiensis , C. balicasag , C. mclaughlinae n. sp. and C. thailandensis and is united by the presence of carinae on the proximal portion of the antennal scales and tricarinate submedian carinae on AS 5. The geographical ranges of many species overlap, but within the aforementioned groups, species have discrete or near discrete ranges. In group 1, C. multicarinata ranges from Japan to the Southern India , whereas C. carita has an adjacent but discrete range along the coast of northern Australia ( Ahyong 2001 ). The single species of group 2 ranges from the South China Sea to Madras, India ( Shanbogue 1986 ). In group 3, C. redacta is known only from northern Australia , C. carinata occurs in the South China Sea from Vietnam to the Gulf of Thailand , south to Indonesia , and C. spinosa ranges from the western Indian Ocean to the Andaman Sea.In group4, C. mclaughlinae n. sp. is known only from the western Indian Ocean, C. balicasag is known only from Balicasag Island ( Philippines ) and C. thailandensis ranges from the Gulf of Thailand to northern Australia , where it overlaps with C. australiensis (see Ahyong 2001 ).