ABSTRACT
Ovigerous females of 10 species of xanthid crabs (Xanthidae MacLeay, 1838), from five subfamilies, namely, Pseudoliomera speciosa (Dana, 1852) (Actaeinae), Chlorodiella cytherea (Dana, 1852), Chl. laevissima (Dana, 1852), Chl. nigra (Forskål, 1775), Cyclodius granulosus (De Man, 1888) (Chlorodiellinae), Danielea noelensis (Ward, 1942) (Euxanthinae), Liomera rugata (H. Milne Edwards, 1834), Lio. tristis (Dana, 1852) (Liomerinae), Lachnopodus subacutus (Stimpson, 1858) and Leptodius sanguineus (H. Milne Edwards, 1834) (Xanthinae), were collected from the Gulf of Aqaba, and the zoea I obtained from them have been described herein. Six species, viz. Chl. cytherea, Chl. laevissima, Cyc. granulosus, Lio. rugata, Lio. tristis and Lep. sanguineus, are described for the first time, and Lac. subacutus and D. noelensis are re-described. Spinulations of dorsal and rostral spines of cephalothorax, length of rostral spine of cephalothorax to protopod of antenna, setations of antennule, ratio of antennal exopod to protopod and setations of exopod of antenna are important characters that distinguish xanthid larvae from their congeners and other closely related species at subfamilial levels.
Subject(s)
Brachyura , Decapoda , Animals , Female , Indian Ocean , LarvaABSTRACT
Portunus pelagicus (Linnaeus, 1758) sensu lato has been recognized as a species complex comprising four species. Of these four species, the larval stages of all except Portunus segnis (Forskål, 1775), have been described. The larvae of P. segnis, hatched from an ovigerous female, caught in the Gulf of Aqaba, were cultured in the laboratory up to the megalopa stage. All the larval stages are described herein for the first time. The number of aesthetascs of the antennules of all the zoeal stages of P. segnis differs from those of the larvae of the other species of the P. pelagicus species complex. In the telson forks of zoea I-IV of P. segnis, there is a pair of ventral spines and two pairs of dorsal spines, whereas in the other P. pelagicus species complex larvae, there is a pair each of ventral and dorsal spines. Another unique feature, in the megalopa of P. segnis, are two endopod hooks in pleonites I-V. Different zoeal and megalopal stages of P. segnis can be distinguished clearly from the other P. pelagicus species complex larvae based on the number of setae and patterns of different appendages.
Subject(s)
Brachyura , Animals , Female , Laboratories , Larva , Saudi ArabiaABSTRACT
The complete larval development of the oziid crab Epixanthus frontalis (H. Milne Edwards, 1834) hatched from ovigerous specimens collected from Saso Island, southern Red Sea, was obtained under laboratory conditions. Four zoeae, one additional zoea and a megalopa were obtained and these are described and illustrated in detail for the first time. Larvae of this species can be differentiated from those of other oziid species based on a combination of characters such as the number of aesthetascs and setae of the antennule, and the coxal and basial setal numbers and patterns of the maxilla and maxillule.
