\ Color.—Mottled Gray and Yellowish White So As to Imitate Sand; First Pair
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\ preceding teeth. One or more small, naked, irides cent areas near anterolateral margin at base of teeth. Chelipeds long, slender; merus with five to seven spines in front, and one behind at distal end; carpus with a large internal and a smaller external spine; hand slender, ribbed on all sur faces ; ribs continued on fingers and roughened by sharp-pointed, appressed tubercles; hand with two spines, one at articulation with carpus, an other near distal end of superior rib; fingers nearly straight with incurved tips. Measurements.—Carapace: male, length, 29 FIGURE 145.—Portunus anceps (Saussure). Male in dor mm.; width, 61 mm. sal view, legs of left side not shown, 5 mm. indicated. Color.—Brownish red, transverse ridges on carapace, spines, and margins of chelipeds car Color.—Mottled gray and yellowish white so as mine red; front side of legs brilliantly iridescent to imitate sand; first pair of legs red or yellow; by lantern light, iridescence evident to some ex chelipeds and other legs same color in part (Ver- tent in preserved material. rill, 1908). Hairs on legs colorless (Abramowitz, 1935). Habitat.—The species is fairly common about Habitat.—This form lives on or near sandy the Beaufort, N.C., region and is often taken in shores in tropical waters, but is sometimes carried deeper channels of the harbor. Along with P. northward in the Gulf Stream to the North Caro spinimanus, Hildebrand (1955) reported this spe lina capes; surface to 40 fathoms. cies as common on the shrimping grounds on Type locality.—Cuba. Campeche Bank in the Gulf of Mexico, but rare Known range.—Cape Hatteras, N.C., to Brazil; on the Texas coast. Surface to 48 fathoms, rarely Bermuda. deeper. Remarks.—Rathbun (1930a) recorded ovige- Type locality.—South Carolina and St. Augus rous females from June in Cuba to October in tine, Fla. North Carolina. Known range.—Southern Massachusetts to Portunus gibbesii (Stimpson) Texas; Venezuela; Surinam. Figure 146 Lupa gibbesii Stimpson, 1859, p. 57. Portunus gibbesii: Hay and Shore, 1918, p. 428, pi. 33, fig. 1.— Rathbun, 1930a, p. 49, pis. 16-17 (rev.). Recognition characters.—Carapace approxi mately twice as wide as long, not tumid, thickly covered with small spherical granules, pubescent, and with three or four naked, transverse ridges, two of which arise from lateral spines and run toward gastric region. Eight frontal teeth includ ing two points of each inner orbital, median pair of frontal teeth narrower and slightly more ad vanced than next pair. External orbital tooth not much larger than teeth of anterolateral border, these latter stout, acute, directed forward; last FIGUBE 146.—Portunus gibbesii (Stimpson). Male in tooth, or lateral spine, slender, sharp, curved for dorsal view, legs of left side not shown, 10 mm. ward and about as long as space occupied by three indicated. 164 FISH AND WILDLIFE SERVICE Remarks.—Ovigerous females have been re ported and are otherwise known to occur in the months February to June from North Carolina to Surinam (Holthuis, 1959; Kathbun, 1930a). Gray (1957) computed gill area per unit weight for P. gibbesii as intermediate among a number of swimming crabs studied. Portunus spinimanus Latreille Figure 147 Portunus spinimanus Latreille, 1819, p. 47.—Hay and Shore, 1918, p. 429, pi. 33, fig. 4.—Rathbun, 1930a, p. 62, text-fig. 10, pis. 26-28 (rev.). Recognition characters.—Carapace considera bly less than twice as wide as long, finely granu late and pubescent, with a number of prominent, curved, coarsely granulate, transverse ridges. Eight frontal teeth, including inner orbitals, each notched at summit and presenting two points; FIGURE 147.—Portunus spinimanus Latreille. Male in median pair of teeth slightly narrower and more dorsal view, legs of left side not shown, 20 mm. advanced than next pair, all considerably more indicated. advanced than inner orbitals. Outer orbital teeth obtuse, not much larger than teeth of anterolat often found in company with P. spinimanus. A eral borders, these latter strong, acute, or acumi similar association of these two species was re nate, about equal in size except last; this tooth ported by Hildebrand (1955) for the Campeche about twice as large as others and usually curved Banks in the Gulf of Mexico where they are com forward. mon. On beach under Sargassum; surface to 50 Chelipeds long, pubescent, serratogranulate all fathoms. over; merus with four, occasionally five, strong, Type locality.—American waters, common in curved spines in front and one at distal end; car Brazil. pus with two spines, inner one much stronger, Known range.—New Jersey through Gulf of and with four conspicuous ridges on upper sur Mexico and West Indies to southern Brazil; Ber face ; hand slender, all surfaces with ridges which muda. extend on fingers; a strong spine at carpal articu Remarks.—This species, which somewhat re lation and another near base of dactyl; fingers sembles P. gibbesii, can be readily distinguished nearly straight, tips incurved. from the latter by its narrower, rounder form, and Measurements.—Carapace: female, length, 55 by the entire lack of iridescent patches on the mm.; width, 88 mm. carapace mentioned for P. gibbesii. Variations.—Large males have relatively Ovigerous females are known from January to longer, thinner chelipeds and longer walking legs July in Florida (Wass, 1955, in part); March in than large females. Campeche; April in Isle of Pines; May, August, Color.—Pubescence yellowish or reddish brown, and September in Surinam (Holthuis, 1959); and ridges of carapace, spines of chelipeds, fingers July in St. Thomas, V.I. (Eathbun, 1930a). Le- and tips of legs reddish brown; anterolateral bour (1950) found an ovigerous female among teeth reddish at base, white at tips; merus, carpus, Sargassum in Bermuda in May, and from the and hand of chelipeds with white blotches. eggs reared larvae which she illustrated. Habitat.—This species is common in the waters Gray (1957) computed gill area per unit weight off Beaufort Inlet, N.C., and is sometimes found for P. spinimanus as intermediate among a num in deeper channels of the harbor. P. gibbesii is ber of swimming crabs studied. MARINE DECAPOD CRUSTACEANS OF THE CAROLINAS 165 763-049 0^65 12 \ Portunus ordwayi (Stimpson) gray; pale orange beneath, deeper orange on Figure 148 chelipeds and legs; chelae deep red brown above, Achclous ordwayi Stlmi)son, 1860a, p. 224. fingers with two cross bands of light orange red. Portunus ordwayi: Hay and Shore, 1918. p. 431, pi. 33, fig. 6. Rathbun, 1930a, p. 71, pi. 33 (rev.). Blue coloration also apparent near red and dark pigments; hairs on appendages deep red (Abram- owitz, 1935). Habitat.—This is another of the tropical swim ming crabs which move northward with warm water currents; surface to 58 fathoms, rarely deeper. Type localities.—Key Biscayne and Tortugas, Fla.; St. Thomas, [V.I.]. Knoion range.—Vineyard Sound, Mass.; North Carolina through Gulf of Mexico, Caribbean Sea, and West Indies to State of Bahia, Brazil; Ber muda. Remarks.—Rathbun (1930a) listed an ovige nous female in March from Florida. Portunus depressifrons (Stimpson) Figure 149 Amphitrite depressifrons Stimpson, 1859, p. 58. FIGURE 148.—Portunus ordwayi (Stimpson). Male in Portunus depressifrons: Hay and Shore, 1918, p. 430, pi. 33, dorsal view, legs not shown except for right eheliped, 10 fig. 7.—Rathbun, 1930a, p. 84, pi. 41 (rev.). mm. indicated. Recognition characters.—Carapace approxi mately 1.6 times as wide as long, uneven, pubes Recognition characters.—Carapace approxi cent, and with indistinct transverse ridges. Six mately 1.5 times as wide as long, uneven, eleva frontal teeth, including inner orbitals much larger tions granulate and depressions pubescent, with a number of conspicuous, curving, transverse than others, tips of all teeth about on a line. Ex ridges. Six frontal teeth including acuminate in ternal orbital tooth strong, tip rounded; antero ner orbitals; true frontal teeth about equal in lateral teeth acute, turned forward, lateral tooth size, triangular, acute, middle pair advanced be scarcely longer than one in front, teeth and inter yond others. Outer orbital tooth large; antero vals between them fringed with hairs. lateral teeth diminishing slightly in size from first Chelipeds trigonal, serratogranulate and pubes to seventh, inclusive, eighth about as long as space cent ; merus with five spines in front and a distal occupied by two preceding teeth, tips of all acute one behind; carpus with two spines, outer much and turned forward. smaller than inner one; hand short and com Chelipeds of moderate length; merus with four pressed, upper margin raised into a crest termi or five strong spines in front, a single distal one nating distally in a stout spine, a smaller spine at behind; carpus ribbed and with strong internal carpal articulation; fingers flattened, dactyl with and much smaller external spine; hand ribbed on border of hairs on superior margin. Walking legs all surfaces except flat, highly iridescent, superior unusually long and slender, first pair with articles surface; superointernal ridge raised into a crest fringed with hairs. Swimming legs shorter than terminating distally in a sharp spine. Margins of in most species of genus. carapace and chelipeds more or less fringed with Measurements.—Carapace: male, length, 26 silky hairs. mm.; width, 41 mm. Measurements.—Carapace: male, length, 26 Color.—Carapace in life irregularly mottled mm.; width, 42 mm. with light and dark gray, closely imitating colors Color.—Carapace and legs reddish brown due of sand; chelipeds and posterior legs similar, to fine mottling with red, yellowish brown, and though paler; first pair of walking legs bright 166 FISH AND WILDLIFE SERVICE Portunus spinicarpus (Stimpson) Figure 150 Achclous spinicarpus Stimpson, 1871a, p. 148. Portunus spinicarpus: Hay and Shore, 1918, p. 429, pi. 33, fig. 3.—Rathbun, 1930a, p. 92, pi. 45. Recognition characters.—Carapace slightly more than twice as wide as long, sculptured, with a number of naked, rather coarsely granulate, arching, transverse ridges separated by finely granulate and pubescent surfaces.