Alpheus hebes Kim and Abele, 1988

Anker, Arthur, Hurt, Carla & Knowlton, Nancy, 2009, Description of cryptic taxa within the Alpheus bouvieri A. Milne-Edwards, 1878 and A. hebes Kim and Abele, 1988 species complexes (Crustacea: Decapoda: Alpheidae), Zootaxa 2153, pp. 1-23 : 10-12

Alpheus hebes Kim and Abele, 1988

Figs. 3 , 5 E

Alpheus hebes Kim and Abele 1988: 62 , fig. 26; Ríos Gonzalez 1989: 118, pl. 22; Ríos 1992: 5; Wicksten and Hendrickx 1992: 5; Hernández-Aguilera and Martinez-Guzman 1992: 4; Vargas and Cortés 1999: 900; McClure and Wicksten 2000: 965, fig. 1; Hickman and Zimmerman 2000: 37; Wicksten and Hendrickx 2003: 64.

[?] Alpheus Bouvieri var. Bastardi (not bouvieri sensu Milne-Edwards 1878 ; not bastardi sensu Coutière 1898 ) Coutière 1898: 133 (part., specimens from Panama).

Material examined. Panama (Pacific coast). 1 male (CL 6.5), USNM 1123864, Las Perlas Islands, small island off Contadora, rocky intertidal, from rock crevices, coll. A. Anker, C. Hurt, E. Gómez, J. Jara and E. Tóth, 31 Mar 2006 [fcn 06-369, specimen dissected]; 1 ovig. female (CL 6.0), MNHN-Na 17184, Las Perlas Islands, Isla del Rey, sta. 2, coll. N. Knowlton et al., 1998.

Diagnosis. Species of Alpheus leviusculus group (Clade L). Frontal margin of carapace with short, subtriangular rostrum; rostral carina not delimited, postrostral area flattened; orbital hoods unarmed, rounded, swollen, markedly but not steeply sloping into shallow orbitorostral grooves. Antennule with second peduncular segment less than twice as long as wide; stylocerite with blunt or subacute tip, not reaching distal margin of first segment. Antenna with basicerite armed with sharp distoventral tooth; scaphocerite with strong distolateral tooth extending only slightly beyond broad blade, not reaching end of antennular peduncle; carpocerite greatly overreaching both scaphocerite and end of antennular peduncle. Third maxilliped not particularly broadened, unarmed. Major cheliped with merus lacking sharp distomesial tooth; chela somewhat compressed, dorsal groove relatively broad and deep, extending mesially as contrasting rounded depression and laterally as well defined, posteriorly extending groove; dorsal shoulder rounded, not overhanging; ventral groove broad and deep, adjacent shoulder rounded, not protruding; adhesive disks small; fingers slightly less than half-length of palm; plunger of dactylus well developed. Minor cheliped sexually dimorphic; palm with very shallow dorsal groove; fingers somewhat broadened and balaeniceps in males, subconical and nonbalaeniceps in females. Second pereiopod with first carpal segment about twice as long as second. Third pereiopod with ischium armed with small ventrolateral spine, merus and carpus unarmed; propodus with row of stout spines, most paired; dactylus stout, simple, conical. Male second pleopod with typical appendices masculina and interna. Uropod with protopod laterally projecting as acute tooth; exopod with distolateral spine bordered laterally by sharp distolateral tooth; transverse suture sinuous, consisting of two rounded lobes and subtriangular tooth adjacent to distolateral spine; both exopod and endopod furnished with row of spinules distally. Telson broad, tapering distally, with two pairs of dorsal spines; posterior margin convex, with two pairs of spines at each posterolateral angle and row of spinules in-between.

Description. See Kim and Abele (1988) and McClure and Wicksten (2000). Complementary figures are provided in Fig. 3 .

Size. Male at CL 6.5 mm and TL 19.3 mm; ovigerous female at CL 6.0 mm and TL 19.0 mm; egg size: 0.5 x 0.65 mm (average from 3 eggs).

Color pattern. Opaque-whitish with broad transverse bands of brown (combination of gray-blue and red chromatophores), two on carapace separated by halfmoon-shaped patch, and one along posterior half of each pleomere; uropods and telson brown except for whitish most proximal part; walking legs semitransparent with red chromatophores; minor chela pale brown; major chela orange-brown mesially, without paler ventroproximal patch and dorsal and ventral grooves; distal half of pollex and dactylus pink, tip whitish; rostrum and rostral carina region brown; antennular peduncles brown; scaphocerite of antenna mostly whitish; antennal and antennular flagella pale yellow ( Fig. 5 E). See also color description in McClure and Wicksten (2000) and color photographs in Hickman and Zimmerman (2000).

Type locality. James Island, Galapagos ( Kim and Abele 1988); type specimens in USNM.

Distribution. Eastern Pacific: Gulf of California; Clarion Island; western Mexico; Costa Rica; Panama; Colombia; Ecuador; Galapagos ( Kim and Abele 1988; McClure and Wicksten 2000).

Ecology. Mid-intertidal, under rocks on sand ( McClure and Wicksten 2000; present study).

Remarks. Alpheus hebes is most closely related to the below described new species (see under A. agilis n. sp.). In the tropical eastern Pacific, A. hebes may be confused with A. javieri n. sp. and A. longinquus , differing from both of them by the shape of the rostrum and post-rostral region, a short, distally blunt or subacute stylocerite, and the presence of a spine on the ischium of the third and fourth pereiopods; in addition, male specimens of A. hebes may be easily distinguished from A. longinquus by the balaeniceps minor chela (see also Kim and Abele 1988).

GenBank access number. FJ937717 (fcn 07-163), FJ937718 (fcn 07-164).

Figures

FIGURE 3. Alpheus hebes Kim and Abele, 1988; male from Las Perlas, Panama (USNM 1123864): A, frontal region, dorsal view; B, stylocerite of antennule, ventrolateral view; C, major chela, lateral view; D, same, mesial view; E, male minor chela, mesial view; F, second pereiopod, lateral view; G, third pereiopod, lateral view; H, appendix masculina and appendix interna of second pleopod; I, uropod, distal region; J, telson, dorsal view. Scale bars: 1 mm.

FIGURE 5. Color patterns of Alpheus bouvieri A. Milne-Edwards, 1878 [western Atlantic] (A); Alpheus bouvieri [eastern Atlantic] (B); Alpheus javieri n. sp. (C, D); Alpheus hebes Kim and Abele, 1988 (E); and Alpheus agilis n. sp. [eastern Atlantic] (F): A, male from Bocas del Toro, Panama; B, female from São Tomé; C, male from Punta Morales, Costa Rica; D, female from Las Perlas, Panama; E, male from Las Perlas, Panama; F, male from São Tomé.