Abstract
Sulaplax gen. nov. and Guaplax gen. nov. are established for two new species of cave-dwelling false spider crabs (Hymenosomatidae) from Muna Island, Sulawesi Tenggara, and Kalimantan Timur, Indonesia, respectively. Sulaplax ensifer spec. nov. and Guaplax denticulata spec. nov. are distinguished from each other by carapace, rostral, pereopodal, abdominal and male gonopodal characters. Sulaplax and Guaplax share with Cancrocaeca Ng, 1991, another troglobitic hymenosomatid, cave-adapted characters like reduced eyes, pale coloration and slender ambulatory legs. However, the gonopods, abdomens and egg-brooding features of Sulaplax and Guaplax are closer to those of the epigeal Neorhynchoplax Sakai, 1938, whereas those of Cancrocaeca are closer to those of the epigeal Limnopilos Chuang & Ng, 1991, and Hymenicoides Kemp, 1917. It appears that the hypogeal lifestyles of Sulaplax-Guaplax and Cancrocaeca species have resulted in many convergent characters.References
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