WILLIAMS: MUD CRAB. PARTITION INTO SIX SPECIES 



Measurements in mm. — A set of measurements for 

 length and width of the carapace of this species is 

 summarized in Tables 1 and 2 and graphically rep- 

 resented in Figure 9. 



Color. — Male somewhat slate blue to dull maroon 

 dorsally, lighter on cardiac and intestinal regions, 

 buff or tannish lines more or less separating regions. 

 Chelipeds with same color as carapace, densest dor- 

 sally but breaking into a reticulate pattern of color 

 made up of discrete dark spots on light background 

 on both inner and outer sides of palm, carpus, and 

 merus, continued nearly to ventral side but spots 

 becoming progressively more widely spaced and 

 lighter ventrally; palm with inner and outer central 

 longitudinal stripe relatively colorless, thin prox- 

 imally but widening distally, a much thinner light line 

 below this on outer side; fingers brown, color con- 

 tinued slightly but variably on palm, tips light. Walk- 

 ing legs tinted dorsally somewhat as carapace but 

 lighter distally (becoming somewhat olive). Eye- 

 stalks with alternate longitudinal stripes of broad gray 

 and narrow dull olive, cornea dark Antennules with 

 dark and lighter slate blue banding, tipped by off- 

 white brush. External maxillipeds with patches of 

 darker and lighter slate blue banded by off-white on 

 merus; ischium with internal burgundy spot near 

 base variable in size. Tips of raised parts on lower 

 side of legs and venter off-white. 



The reticulate pattern on the outer surface of the 

 palm may fade but basically remains after long pre- 

 servation in 70% ethanol. (From specimens at 

 Beaufort, N.C., and preserved in the USNM.) 



terial from Aspinwall (= Colon, Panama) in the type- 

 series of his variety, but it is evident, after 

 examination of that type-series in the YPM, that the 

 Panama material is Panopeus lacustris. The Egmont 

 Key specimen is a well-preserved immature female, 

 cl 8.7 mm, cw 13.0 mm, which lacks one leg, the first 

 walking leg on the left side. 



The general shape of the carapace fits that for P. 

 obesus at this stage of development: smooth dorsally, 

 branchial areas somewhat inflated, arched antero- 

 posteriorly; anterolateral teeth rounded at apices, 

 first two being almost completely coalesced; front 

 not prominent. 



The chelipeds are representative of a large series of 

 the specimens examined, though not fully developed 

 at this size. The right major chela has a well- 

 developed tooth row on the fixed finger with proximal 

 molar area prominent, not broadened, and with cusps 

 somewhat sectorial in nature, forming a row in line 

 with the trend of the finger. The minor chela has a 

 somewhat damaged fixed finger, the distal one- 

 fourth having apparently been broken off but healed; 

 otherwise it is characteristic. 



There is no indication of color or color pattern, 

 except for brownish gray darkening of the fingers on 

 both chelae, with tips of fingers and cusps of teeth 

 lighter, and a definite faded internal basal oval spot 

 on the ischium of the third maxillipeds. 



Other remarks are given in the general discussion 

 below. 



Panopeus simpsoni Rathbun, 

 new rank 



Type-locality. — The type-locality is hereby restricted 

 to Egmont Key (mouth of Tampa Bay), Fla. 



Known range. — The known geographic range of this 

 species, represented by material listed above, is 

 marsh edge, shallow intertidal, and subtidal waters of 

 the Carolinian Province from environs of Beaufort, 

 N.C., to Georgia (and perhaps northeastern Florida), 

 and from Sarasota County, Fla., to Louisiana. D. L. 

 Felder 4 has records of the species from Texas and 

 northeastern Mexico. Reames and Williams (1983) 

 and Sullivan et aL (1983) show that the species is 

 mainly associated with marshlands of the Carolin- 

 ian Province. 



Remarks. — Smith (1869a) included syntypic ma- 



4 Darryl L. Felder, Associate Professor, Department of Biology, 

 University of Southwestern Louisiana, Lafayette, LA 70504, pers. 

 commun. 1981-82. 



Figure 8 



Eupanopeus herbstii. — Rathbun 1900b: 138 (key, 

 part). 



Panopeus herbstii forma simpsoni Rathbun 1930:337, 

 pi. 157, figs. 1-2.— Martin et al. 1984:537-602, 

 figs. 106, lib, 136 ii, 14,18, 23bii, 24,25, 336ii, 34, 

 35,36, 46,47. 



Panopeus herbstii. — Rathbun 1930:340-342 (part, 

 forma typica from Gulf of Mexico and Baha- 

 hamas).— Behre 1950:24 (list).— Williams 1965:196 

 (part).— 1984:412 (part).— Felder 1973:69 (part, 

 key).— Powers 1977:102 (part, notes). 



Panopeus herbstii forma typica. — Behre 1950:24 

 (list). 



Panopeus herbstii forma Stimpson. — Pounds 

 1961:4 (list), pi. IX, fig. 2.— Leary 1964 and 

 1967:44 (list), unnumbered plate and fig., p. 39. 



Panopeus herbstii forma simpsoni. — Heard 1982:50, 

 fig. 55a-c. 



875 



