WILLIAMS and CHILD: COMPABISONS OF SOME BOX CRABS 



ity in ornamentation. However, body proportions of 

 the two species differ, as exemplified by the rela- 

 tionship of interorbital width to maximum span 

 between posterolateral projections of the carapace 

 (Fig. 2A, F, iV = 40, X = 0.519, SD = 0.057). 

 Other differences include shape of the proximo- 

 ventral crest on the extensor face of the cheliped 

 palm, rounded in the former, ending anteriorly in 

 a subrectangular point in the latter, and in shape 

 of the male pleopod 1 (see Figures 1 and 4). Cyclo- 

 zodion tuberatum most closely resembles Calappa 

 angustum, although there are superficial similarities 

 to fossil Calappilia scopuli Quayle and Collins as 

 pointed out below. 



Paracyclois Miers 1886 



Paracyclms Miers 1886:288. Type species, P. milne- 

 edwardsii Miers 1886:288.-Glaessner 1969:R494 

 (part, not Calappilia). 



Diagnosis paraphrased and emended. —Carapace 

 about as long as broad, and moderately convex; 

 front narrow and trilobate; median lobe rounded and 

 much broader than lateral lobes; without lateral 

 epibranchial spine or tooth; anterolateral margins 

 regularly arcuate, broadest span anterior to junc- 

 ture with posterolateral margin; each posterolateral 

 margin bearing strongly spiniferous lobe or wing- 

 like projection, width between principal spines on 

 lobes less than greatest width of carapace (postero- 

 lateral winglike prolongations more fully developed 

 in Calappa); axis of principal spine on winglike pro- 

 jection diverging from midsagittal line at angle of 

 25-40°. Subhepatic regions of carapace concave; 

 channel thus formed communicating with antennary 

 region (and thereby with buccal cavity) by a notch 

 situated between it and inferior wall of orbit. Pos- 

 terior abdominal segments distinct. 



Eyes large, peduncles short, robust, closely en- 

 cased in oval orbits scarcely raised above surround- 

 ing area; interorbital distance at least 0.40 and 

 usually 0.45-0.60 or more of span between tips of 

 principal spines on posterolateral margin. Anten- 

 nules folding obliquely; antennae with quadrate 

 basal article not reaching frontal margin, flagellum 

 very short. Outer maxillipeds with ischium longer 

 than broad, longer than distally truncate merus with 

 its anterointernal angle distinctly notched. Pereo- 

 pods 2-5 with row of spines on flexor surface of 

 ischium-merus. 



Remarks.— Miers (1886, emended) considered 

 Paracyclois to be an apparent connecting link be- 



tween Calappa, Cycloes De Haan 1837, and Platy- 

 mera H. Milne Edwards 1837 in which the merus 

 of the outer maxilliped is distally truncate and bears 

 the next article at its anterointernal angle, which 

 is prolonged in the form of a lobe or tooth; but 

 Paracyclois is distinguished from the first two of 

 the above-mentioned genera by the absence of any 

 lateral spine on the margin of the carapace and the 

 broader basal antennal article, and from Calappa 

 by both the reduced winglike prolongations of the 

 carapace which bear strong spines, and by presence 

 of spines on the flexor margin of the ischium and 

 merus of pereopods 2-5. 



Key to species of Paracyclois 



1. Carapace with 3 obviously projecting lobulate 



spines on posterior margin 



P. milneedwardsii 



Carapace with posterior margin only faintly 

 trilobed P. atlantis 



Paracyclois atlantis Chace 1939 



Figures 2, 5 



Paracyclois atlantis Chace 1939:51.-1940:27, figs. 



11, 12. 



Material studied.— Silver Bay stn.— 3467. 1 a; off 

 Grand Bahama Bank, 27°27'N, 79°00'W, 228-274 

 m; dredge, 25 Oct. 1961.-3510. 2 a; Santaren 

 Channel, 22°55'N, 78°36'W, 273 m; dredge, 7 Nov. 

 1961. -USNM 81986. 1 9; off Punta Alegre, Cuba, 

 22°46.5'N, 79°W, 329 m; Atlantis stn. 3419, 30 Apr. 

 1939.-Oregon stn. 2603. 3 ct, 1 9 (ovig.); Puerto 

 Rico, E San Juan, 18°30'N, 65°55'W, 256-292 m; 

 trawl, 25 Sept. 1959.-5914. 1 o-, 2 9, Leeward Is., 

 W Anguilla I., 18°13'N, 63°19'W, 201 m; dredge, 

 25 Feb. 1966.-6700. 3 o-; S Barbuda I., 17°27'N, 

 62°04'W, 248-285 m; trawl, 19 May 1967.-3636. 

 1 o-; Belize, 17n7'N, 87°59'W, 228 m; trawl, 10 

 June 1962.-4445. 1 juv.; Netherlands Antilles, S 

 Bonaire, 10°50'N, 68°00'W, 183 m; trawl, 10 Oct. 

 1963.-4856. 1 9; Colombia, off Barranquilla Is., 

 11°08'N, 74°23.8'W, 183 m; trawl, 19 May 1964.- 

 Oregon stn. 3585. 1 O"; Panama, Gulf of Mosquitos, 

 09°12'N, 81°30'W, 247-256 m; trawl, 25 May 

 1962.-3587. 1 o-; Panama, Canal Zone, 09°18'N, 

 80°25'W, 137 m; trawl, 29 May 1962.-1983. 1 9; 

 Venezuela off Orinoco R. mouths, 09°53'N, 

 59°53'W, 228 m; trawl, 3 Nov. 1957.-2294. 1 9; 

 Surinam E of Paramaribo, 07°25'N, 54°08'W, 

 192-210 m; trawl, 9 Sept. 1958. 



115 



