CYCLOGRAPSVS INTEGER H. MILNE EDWARDS, 1837 



(BRACHYURA, GRAPSIDAE): THE COMPLETE LARVAL DEVELOPMENT 



IN THE LABORATORY, WITH NOTES ON LARVAE OF 



THE GENUS CYCLOGRAPSUS 



Robert H. Gore and Liberta E. Scotto 1 



ABSTRACT 



r T 



The complete larval development of Cyclograpsus integer, a small sesarmine grapsid crab, is de- 

 scribed and illustrated from larvae reared in the laboratory. Cyclograpsus integer attains five, and 

 often six, zoeal stages plus one megalopal stage. Temperature affects both duration of larval devel- 

 opment and number of larval stages. At 25°C, the megalopal stage was attained in 26-27 days from 

 fifth stage zoeae and 31-32 days from sixth stage zoeae, while metamorphosis at 20°C occurred in 

 53-55 days from sixth stage zoeae. The zoeal and megalopal stages of C. integer are compared to all 

 known cultured species of the genus and morphological differences are noted. Cyclograpsus integer 

 zoeae may be distinguished from both other species in the genus and other species in the family by its 



antennal morphology, being the only species with the type A antenna(i.e.,theexopodite about equal 

 in length to the protopodite). Megalopae of this species may be distinguished from other species in 

 the genus by the formation of the frontal region and the terminal setation of the telson. Other poten- 

 tially useful zoeal morphological characters are discussed regarding both the taxonomicand phylo- 

 genetic position of C. integer. 



The sesarmine genus Cyclograpsus is cosmopoli- 

 tan, containing at least 16 species, 13 of which 

 occur in the Indo-West Pacific region (Griffin 

 1968). Cyclograpsus integer, one of four species in 

 the genus occurring in the New World and the 

 only one known from the western Atlantic, is 

 quite widespread with records from western and 

 eastern Africa, and localities in the Indo-West, 

 eastern central, and northern west Pacific Ocean 

 (Monod 1956; Griffin 1968; Manning and Hol- 

 thuis 1981). Although Rathbun (1918) listed the 

 Peruvian and South American species Cyclo- 

 grapsus cinereus Dana, 1851 as being the eastern 

 Pacific analog to C. integer, Griffin (1968) noted 

 that Cyclograpsus escondidensis Rathbun, 1933, 

 an eastern Pacific species known only from Cen- 

 tral America, was closer to C. integer than to any 

 other member of the genus. In the same study, 

 Griffin described Cyclograpsus sanctaecrucis, a 

 new species from Santa Cruz Island in the south- 

 western Pacific Ocean, stating that "Except in 

 the presence of a lateral notch on the carapace, 

 [this] species most closely resembles C. integer." 

 Thus, Cyclograpsus integer appears similar to at 



'Smithsonian Institution, Fort Pierce Bureau, Ft. Pierce, 

 FL 33450. 



Manuscript accepted January 1982. 

 FISHERY BULLETIN: VOL. 80, NO. 3. 1982. 



least two other species in the genus from the 

 Pacific Ocean. 



The larvae of members of the genus are not 

 well known, and the complete larval develop- 

 ment has been determined for only two New 

 World species at present. Costlow and Fagetti 

 (1967) described and illustrated the complete de- 

 velopment of C. cinereus from Chile, and in a sub- 

 sequent paper Fagetti and Campodonico (1971) 

 recorded the development of a species from Juan 

 Fernandez Islands which they identified as 

 Cyclograpsus punctatus H. Milne Edwards, 

 1837. Griffin, however (1968), suggested that 

 specimens of Cyclograpsus from those islands 

 are actually referable to Cyclograpsus lavauxi 

 H. Milne Edwards, 1837, stating that C. puncta- 

 tus is restricted to South Africa. To add to this 

 confusion, Wear (1970) described and illustrated 

 the first zoeal stages of two New Zealand species, 

 Cyclograpsus insularum Campbell and Griffin, 

 1966, and C. lavauxi. But a comparison of his 

 illustrations of the latter species with the first 

 zoeal stage figured by Fagetti and Campodonico 

 shows substantial differences in the number and 

 position of chromatophores, appendage pro- 

 cesses, and segmentation of the maxillule, sug- 

 gesting that notable variation occurs between 

 eastern and western Pacific populations of C. 



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