B 



Figure 209. — Large chela of male, view of inner side ; A, 

 Uca minax (Le Conte) ; B, Uca pugnax (Smith) ; C, 

 Uca pugilator (Bose) ; 20 mm. indicated. 



directions, finely granulate, except somewhat 

 coarsely so near anterolateral angles; a shallow 7 

 H-shaped depression near center of carapace, and 

 a horizontal depression behind orbit. Lateral 

 margins nearly vertical ; anterolateral angles 

 slightly produced, continued backward and in- 

 ward as a low, well-defined ridge, and above orbits 

 as a low revolute ridge. Front greater than one- 

 third frontoorbital width, broadly convex. Orbits 

 large, open, eyebrow 5 times as wide as deep, lower 

 margin dentate; eyestalks long, slender. Anten- 

 nules and antennae small, flagellum of antennules 

 hardly visible. Merits of second maxilliped with 

 never more than 10 exceedingly slender spoon- 

 shaped hairs. 



Chelipeds in male very unequal, in female equal 

 and of small size. Large chela with upper surface 

 of merus sparingly granulate, inner edge denticu- 

 late, outer edge granulate; carpus tuberculate. 

 Upper and outer face of large hand in male with 

 tubercules diminishing to granules on lower face, 

 ridged al>ove; inner surface with an oblique row 

 of granules from lower margin to carpal cavity, 

 a short curved row leading down from ridge on 

 upper margin, area between ridges tuberculate 



and with a tuberculate ridge running along im- 

 movable finger from tip to internal distal border 

 of palm. Fingers strong, with wide gape, cutting 

 edges tuberculate; immovable finger with a few- 

 larger teeth at irregular intervals, truncate at tip ; 

 dactyl longer and curving downward past tip of 

 opposed finger. Walking legs strong, sparsely 

 hairy, meri slightly wrinkled. 



Measurements. — Carapace : male, length, 25 

 mm. ; width, 38 mm. 



Color. — Chestnut brown, becoming gray in 

 front; chelipeds with red spots at articulations; 

 hands ivory white ; legs olive or grayish brown. 



Habitat.— This species occurs in marshes at 

 some distance from water of high salinity. It is 

 usually found on muddy substrates where flood- 

 ing with fresh water occurs (Teal, 1958), or on a 

 mud and sand substrate (Gray, 1942). In North 

 Carolina, the species is found in Spartina marsh, 

 often far from banks of ditches, and in the area 

 immediately preceding the Salicornia-Disticlilis 

 zone (Vernberg, 1959). It has also been observed 

 at the edge of low woodlands (Teal, 1959). The 

 crabs live in burrows which they dig to various 

 depths, but the maximum is about 2 feet. The 

 openings are often considerably above high-tide 

 level, and the bottoms reach to ground-water level. 

 The burrows are only wide enough to accommo- 

 date the occupant. Usually only one crab lives in 

 a burrow, though at times two females may oc- 

 cupy a single burrow, and burrows of females 

 sometimes communicate with burrow's of males, 

 the connection being made by the female (Gray, 

 1942). Young crabs are sometimes found in the 

 burrows of females, never in those of males. 



Type locality. — Beesleys Point, N.J. 



Known range. — Buzzards Bay (Wareham), 

 Mass., to Matagorda Bay, Tex.; Colombia; Do- 

 minican Eepublic. 



Remarks. — This species has been the subject of 

 a number of ecological and physiological studies, 

 undoubtedly because of its wide distribution and 

 accessibility. It is the largest of the three species 

 of fiddler crabs occurring on the east coast of the 

 United States, though it is not so abundant as 

 the other two species and its habitat is somewhat 

 more restricted. 



Spawning occurs in the Carol inas and as far 

 north as mid-Chesapeake Bay in summer. In 

 Chesapeake Bay, ovigerous females are most 



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FISH AND WILDLIFE SERVICE 



