WILLIAMS: CRABS OF THE GENUS CALLINECTES 



Metagastric area with length approximately 

 equal to posterior width, anterior width about 2 

 times length. Anterolateral margins moderately 

 arched, teeth exclusive of outer orbital and lateral 

 spine varying from triangular or inflated triangu- 

 lar at inner end of row through acuminate forward 

 trending intermediate teeth to forward curving 

 spiniform tooth at outer end of row, base of first 

 and last tooth narrowest. Surface of carapace 

 coarsely granulate and uneven, nearly smooth 

 around margins and along regional sulci, more 

 granulate over branchial and gastric areas, most 

 closely crowded granules on cardiac, mesobran- 

 chial, and anterior half of mesogastric regions. 

 Epibranchial line prominent and nearly uninter- 

 rupted. 



Propodus and carpus of chelipeds with sharply 

 and rather coarsely granulated ridges, especially 

 on propodus, rarely worn smooth; dactyl of major 

 chela with basal teeth (often a single strong tooth) 

 closing against cuspate molariform complex on 

 propodus, both chelae with sectorial teeth. 



Male abdomen and telson reaching beyond mid- 

 length of thoracic sternite IV; telson much longer 

 than broad, triangular with inflated sides; sixth 

 segment of abdomen narrowest in proximal third. 

 Mature female abdomen and telson reaching no 

 more than midlength of thoracic sternite IV; tel- 

 son elongate triangular with inflated sides, sixth 

 segment longer than fifth. First gonopods of male 

 (Figures 18i, 201) very long, reaching to or beyond 

 suture between thoracic sternites IV and V; sinu- 

 ously curved, overlapping proximally, diverging 

 distally, twisting mesioventrally on axis at mid- 

 length of thoracic sternite V and recurving to ter- 

 mination near midline; armed distally with lat- 

 eral band of retrogressive spinules thinning to 

 absence near tip. Gonopores of female (Figure 22i) 

 asymmetrically and narrowly ovate in outline 

 with apex on long axis directed anteromesad; 

 rounded borders with series of wrinkles conform- 

 ing to contours; aperture of each sloping from sur- 

 face on mesial side under anterolateral border su- 

 perior to a rounded eminence on posterior border. 



Size of carapace in mm. — Largest male: length 

 88, width at base of lateral spines 156, including 

 lateral spines 193. Largest female: length 74, 

 width at base of lateral spines 133, including lat- 

 eral spines 174. Estevez (1972) reported a female 

 with carapace 75 mm long estimated to have a 

 width including lateral spines of 182 mm, and 

 estimated general growth rate per molt to be 15% 



in length, 24% in width. Summary of selected 

 measurements is given in Tables 1 and 2. 



Variation. — This species attains the largest size 

 in the genus, but old individuals apparently do not 

 show teeth or spines worn to an extent comparable 

 with other species. Anterolateral teeth vary indi- 

 vidually in degree of laterally progressive upturn- 

 ing in the row. Submesial frontal teeth vary con- 

 siderably in length as well as acuity, but none are 

 really sharp pointed. Chelae in seemingly old in- 

 dividuals retain basal teeth with well defined 

 molariform structure on the major hand; sectorial 

 tooth development seems more prominent on both 

 right and left chelae than in other species. 

 Females have granules more prominent and 

 closely crowded on the carapace than males. Male 

 first gonopods cross over each other at the tips in 

 some individuals. 



Distribution. — Cabo de San Lucas, Baja 

 California, to extreme northern Peru; extrater- 

 ritorial, Juan Fernandez (Figure 27). 



Habitat. — Ranging from shore to 27-m depths, 

 C. toxotes has been characterized as a mangrove 

 swamp crab (Estevez, 1972). It occurs from 

 freshwater streams to open bays, and a number of 

 collections come from lagoons or river mouths. 



Stomachs of 521 specimens contained bivalves, 

 gastropods, inorganic debris, crustaceans, fishes, 

 and polychaetes in order of precedence (Estevez, 

 1972). 



Spawning. — Material available for study in- 

 cludes only three ovigerous females: January, 

 Panama; August, Acapulco, Mexico; a third un- 

 dated specimen from Cabo San Lucas, Baja 

 California, in MCZ was collected by John Xantus, 

 perhaps with the type material. 



Only one-third of the specimens of C. toxotes 

 in museum collections are sexually mature, and 

 among these males outnumber females 2:1. The 

 small number of ovigerous females should there- 

 fore not cause surprise. 



Economic importance. — The species is used as 

 food and sold at the market of Buenaventura, Co- 

 lombia. Crabs there are brought from Malaga Bay 

 and others, many (mostly immature) being caught 

 by shrimpers along the coast (Mario Estevez, 

 pers. commun.). Collections from Estados de 

 Sinaloa and Nayarit, Mexico; Tumaco, Colombia; 



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