Resumen de First Description of the First Crabs of Thalamita Chaptalii (Audouin, 1826) (Crustacea: Brachyura: Portunidae) from the Saudi Arabian Red Sea

Indra Effendy, Anand A. J. Kumar, M. M. El-Sherbiny

• Twenty-six Thalamita chaptalii first crabs were obtained from plankton-caught megalops from the Obhur Creek, Central Red Sea, Saudi Arabia. The first crabs, identified as T. chaptalii using 16S ribosomal RNA gene sequencing, are morphologically described. Setal patterns of T. chaptalii are compared with those of T. crenata and T. danae. Scanning electron microscope (SEM) image of a minute appendage like the cutting edge of mandibles is also given. Morphological features previously unreported in Portunidae first crabs – posteriorly serrated long setae of the epipods of the first and second maxilliped and the outer margin of the ischium of third maxilliped lined by serrated and simple setae – are also studied with SEM images