Alpheus cylindricus Kingsley 1878

Alpheus cylindricus Kingsley, 1878

Alpheus cylindricus Kingsley, 1878a:196; 1878c:58; 1883:120.—Lockington, 1878:478.—Coutière, 1899:29, figs. 44, 278.—Zimmer, 1913:394.—Crosnier and Forest, 1965b:606; 1966:257, figs. 16a–h.—Hendrix, 1971:71.—Coelho and Ramos, 1972:149.—Chace, 1972:65.—Pequeqnat and Ray, 1974:246, fig. 49d.—Christoffersen, 1979:310.—Wicksten, 1983:43.

Alpheus vanderbilti Boone, 1930b:163, fig. 5A–C, pl. 58.

Crangon cylindricus.—Schmitt, 1924c:74; 1939:24.—Chace, 1937:121.—Pearse, 1950:150.

MATERIAL EXAMINED.—Mexico: San Gabriel Bay, Espiritu Santo Island, Baja California (sta 634-37: 1 , 1 ovig, sta 638-37: 2 , 1 , 3 ovig); Isabel Island, Sinaloa (sta 124-33: 1 , 1 ovig).

Costa Rica: Puerto Culebra (sta 256-34: 1 , sta 258-34: 1 ); Parker Bay (sta 473-35: 1 ).

Panama: Pinas Bay (sta 436-35: 1 ovig, sta 437-35: 1 , 1 , sta 444-35: 5 , 2 ovig); Bahia Honda (sta 861-38: 2 ); Secas Isle (sta 446a-35: 1 ).

Colombia: Port Utria (sta 232-34: 2 , sta 234-34: 2 , sta 239-34: 1 ovig, sta 413-35: 1 ovig, “sta 414 or 419-35”: 5 , 1 , sta 419-35: 1 , 1 , 1 ovig); Cupica Bay (sta 427-35: 1 ovig); Gorgona Island (sta 411-35: 1 , 1 ovig).

MEASUREMENTS.—Males, cl 6.1–9.5 mm; females, cl 4.8–7.6 mm; ovigerous females, cl 5.6–9.3 mm.

DESCRIPTION.—Rostrum (Figure 19a,b) blunt, shallowly triangular, slightly produced anteriorly and directing downward at tip.

Ocular hood not inflated dorsally, with anterior margin sinuous.

First antennular segment bearing deep, hook-like carina extending from ventral inner margin; ventral part of carina very acute (Figure 19c). Second segment very long about 3.2 times as long as broad, 1.9 times as long as visible part of first segment and 2.4 times as long as third segment. Stylocerite short, blunt at tip and slightly overreaching middle of first segment.

Scaphocerite about 3.1 times as long as broad. Lateral margin concave at middle. Distal spine reaching to distal of third antennular segment. Inner blade vestigial, reaching to distal ⅕ of second antennular segment. Cleft between inner blade and distal spine invisible, arising from distal of scaphocerite.

Carpocerite reaching to distal end of antennular peduncle. Basicerite with no distinct lateral spine.

Third maxilliped (Figure 19d) reaching to distal end of carpocerite beyond distal half of ultimate segment. Ultimate segment about 1.3 times as long as penultimate, tapering distally, bearing scattered setae on superior and inferior margins as well as on distal margin; tufts of setae on inner face very dense. Penultimate segment rather elongate, about 3 times as long as broad, bearing seta-like movable spines along distal of inferior margin and superior distal margin; inferior margin bearing scattered long setae. Antepenultimate segment bearing seta-like movable spines along distal of inferior margin and scattered long setae on entire inferior margin. Exopod reaching to proximal of penultimate segment. Precoxa with one arthrobranch near distal end but with no supplementary arthrobranch.

Major first pereopod (Figure 19e,f) overreaching distal end of carpocerite by length of chela. Major chela about 3.0 times as long as broad with fingers occupying distal . Movable finger opening and closing in obliquely horizontal plane, elongated cylindrical in shape and bulbous at tip; middle part of finger fitting into concavity near immovable finger. Immovable finger very small. Palm swollen laterally with superior and inferior margins rounded, lacking transverse grooves. Outer face of palm with two longitudinal grooves; groove above inferior crest extending posteriorly just before half length of palm; groove below inferior crest extending posteriorly to half of superior groove and anteriorly to middle of immovable finger. Inferior crest ending in bluntly acute tooth flanking dactylar articulation. Inner face of palm with short, broad superior longitudinal groove behind dactylar articulation. Merus about 1.9 times as long as broad; inferior inner margin smooth, with no spine at distal end.

Minor chela of first pereopods (Figure 19g,h) about 3.9 times as long as broad with fingers occupying distal ; fingers much narrower than palm, strongly deflexed inward and slightly directed downward. Palm swollen laterally and lacking sculpturing. Chela bearing scattered long setae on inferior margin. Merus about 2.1 times as long as broad; inferior inner margin smooth and superior margin very convex.

Second pereopod (Figure 19i) reaching distal end of carpocerite beyond part of first carpal segment. Fingers of chela about 1.9 times as long as palm. First segment of carpus 1.7 times as long as second; second segment 3 times as long as third; third segment subequal to fourth; fifth segment shorter than second, 2 times as long as fourth.

Dactylus of third pereopod (Figure 19j) very small, biunguiculate, strongly deflexed downward, about ⅕ length of propodus. Propodus slightly shorter than carpus, bearing 7 movable spines on inferior margin and pair at distal end; distalmost spine reaching to distal of dactylus. Carpus with tooth-like process on superior distal margin. Merus broad at middle, about 3.2 times as long as broad and 1.5 times as long as carpus. Ischium with no movable spine.

Fourth pereopod almost same as third pereopod. Ischium with no movable spine.

Fifth pereopod much narrower than third pereopod. Ischium with no movable spine.

Pleura (Figure 19k) of first four abdominal somites broadly rounded; pleuron of fifth somite broadly rectangular. Abdominal sternites with no spine at midline. Appendix masculina clearly longer than Appendix interna.

Telson (Figure 19l) regularly tapering posteriorly, about 1.5 times as long as broad at anterior end, armed with two pairs of rather stout dorsal spines and with slight longitudinal median depression on dorsal surface. Posterior margin straight to produced at middle, armed with pair of stout spines at each lateral end; inner spine very strong, about 1.5 times as long as outer one.

Uropodal endopod bearing fairly strong spines along distolateral margin and with inner depression at anterior half invisible. Uropodal exopod with transverse suture forming two straight lobes; lateral margin terminating in sharp immovable tooth flanking movable spine; spine reaching to distal margin of uropodal exopod; immovable tooth inside of movable spine acute.

HABITAT.—Shore to 37 m; sand, rock, and coral clumps.

COLOR IN LIFE.—Carapace spotted on sides, whitish; whole animal pale white on middorsum, sides and head to hind end vermillion, pale; chelae suffused ochraceous-rufous (color note by W.L. Schmitt, unpublished; Wicksten, 1983:44).

TYPE-LOCALITY.—Archipelago de la Perlas, Gulf of Panama. DISTRIBUTION.—Eastern Atlantic from Islands of Principe, São Tome and Annobon Islands; western Atlantic from Bimini, Bahamas, Bermudas, and Florida through Barbados to Bahia, Brazil; Flower Garden Reefs off Texas; eastern Pacific from Gulf of California, Colombia, Gulf of Panama and Galapagos Islands. Now reported from Costa Rica.