Zuzalpheus brooksi ( Coutière, 1909 ) Ríos, Rubén & Duffy, J. Emmett, 2007

Ríos, Rubén & Duffy, J. Emmett, 2007, A review of the sponge‑dwelling snapping shrimp from Carrie Bow Cay, Belize, with description of Zuzalpheus, new genus, and six new species (Crustacea: Decapoda: Alpheidae), Zootaxa 1602 (1), pp. 1-89 : 14-15

Zuzalpheus brooksi ( Coutière, 1909) n. comb.

( Plate 1 )

Synalpheus brooksi Coutière, 1909 : Dardeau 1984: pp 26–38, Figs. 11–14 (and synonymy); Morrison et al. 2004; Mac-

donald et al. 2006; Macdonald and Duffy 2006: Fig. 16 .

Material examined. (1) Syntype ♂ and ♀ ( USNM 24782 ), 3.2 and 3.3 mm (rostrum excluded), respectively, off St. Thomas , Virgin Islands .

(2) 1 ♀ ( VIMS 93 CBC2502), 4.0 mm , 3 ♂ ( VIMS 93 CBC2503, 93CBC2505, 93CBC2506), 3.5–3.7 mm, from larger colony, Twin Cays , Belize, 21 March 1993, in Lissodendoryx colombiensis , 1.5 m .

(3) 1 ♀, 8 ♂ ( VIMS 98 CBC0802-10), Sand Bores , Belize, 4 December 1998, in Hyatella intestinalis , 2 m .

(4) 2 ♂ ( VIMS 05 CBC0220-21), Blue Ground Range , Belize, 9 July 2005, in L. colombiensis , 1– 2m .

(4) 1 ovigerous ♀ ( VIMS 93 P2104), 4.4 mm, 2 ♂ ( VIMS 93 P2105, 93P2106), both 3.4 mm, from larger colony, Cayos Limones , San Blas Islands, Panama, 26 September 1993, in Spheciospongia vesparium , 2 m.

(5) 2 ovigerous ♀ ( VIMS 93 P1407), both 2.3 mm, from larger colony, Tiantupo reef, San Blas Islands, Panama, 22 September 1993, in Agelas clathrodes , 9 m.

Diagnosis. Body form subcylindrical; carapace smooth, with pterygostomian corner very obtusely angular, and posterior margin with cardiac notch distinct. Rostrum clearly narrower than, and about as long as, ocular hoods, distally upturned; margins in dorsal view concave or convex. Orbitorostral process absent. Ocular hoods dorsally convex; in dorsal view, acute, margins convex, separated from rostrum by deep adrostral sinus. Ocular processes absent. Ocellary beak in lateral view rodlike. Stylocerite stocky; mesial margin slightly concave; tip blunt; distinctly shorter than first segment of antennular peduncle; this latter segment without mesio-ventral tooth, and with 2 basal ventral processes. Basicerite without spine on dorso-lateral corner, with longer lateral spine clearly overreaching tip of stylocerite but usually falling slightly short of scaphocerite spine. Scaphocerite with blade absent, acute lateral spine with lateral margin straight, not overreaching antennular peduncle; mesial projection at base of scaphocerite present. Maxilliped 3 with distal circlet of spines on distal segment, and without ventro-distal spine on antepenultimate segment

Major pereopod 1 massive, fingers clearly not longer than half length of palm; fixed finger about as long as dactyl; in ventral view, outer face of fixed finger without distinct protuberance. Palm of chela with distal superior margin produced into tapering acute spine. Merus extensor margin strongly convex, ending in obtuse angle.

Minor pereopod 1 with palm clearly less than two times longer than high; fingers clearly shorter than palm; dactyl with flexor margin straight, blade-like, terminating in two distinct distal teeth, subequal in length, and parallel to dactyl axis; transverse dorsal setal combs on extensor surface of dactyl very conspicuous; fixed finger with flexor margin straight, blade-like, and terminating in two distinct teeth subequal in length. Extensor margin of merus convex, ending in right angle.

Pereopod 2 carpus with five segments; and equal to or shorter than merus.

Pereopod 3 slender; dactyl biunguiculate, with clearly unequal ungues (teeth); proximal tooth wider at base than distal one; merus without movable spines on flexor margin; mesial lamella on coxa present.

Pleura 1 of male with posteroventral corner distinctly produced, hook-like; pleura 2 of male rounded to obtuse. Pleopod 1 of male with few terminal setae on endopod; pleopod 2 of male with marginal setae on exopod originating near midpoint; appendix interna on male pleopods 2–5 present. Telson, space between posterior marginal spines equal to or less than one third width of posterior margin; marginal convex lobe present; posterior corners adjacent to spines rectangular. Anal flaps, perianal setae, and postanal setal brush all absent. Uropods with a single fixed tooth on outer margin of exopod anterior to movable spine.

Color ( Plate 1 ). Non-descript, transparent body, with distal palm and fingers of major chela orange. Ovaries and embryos variable in color, from pale green to gray to pale pink.

Hosts and ecology. Zuzalpheus brooksi occurs within several species of sponges, usually in dense groups of 10s to 100s, or even 1000s in a single sponge ( Pearse 1932, 1950). These groups often have a paucity of ovigerous females ( Duffy 1996b), and thereby appear intermediate in social structure between the apparently ancestral condition of heterosexual pairs common among alpheids, and the several eusocial species that live in large colonies with a single breeding female ( Duffy et al. 2000). In Belize Z. brooksi is reliably found in the loggerhead sponge Spheciospongia vesparium ( Duffy 1993) and in Lissodendoryx colombiensis , usually in shallow depths (less than 5 m).

Distribution. Western Atlantic: Bahamas ( Coutière 1909; Pearse 1950; Lemaitre 1984); Biscayne Bay, Florida ( Dobkin 1965); Florida Keys ( Coutière 1909; Heard and Perlmutter 1977, Duffy 1993); Dry Tortugas ( Coutière 1910; McClendon 1911; Pearse 1932); Gulf of Mexico ( Coutière 1909; Lyons et al. 1971; Dardeau 1984; Erdmann and Blake 1987); Yucatan peninsula ( Coutière 1909; Chace 1972); Cuba (Martínez Iglesias and García Raso 1999); Puerto Rico ( Rathbun 1901; Coutière 1909); St. Thomas, US Virgin Islands ( Coutière 1909); Leeward Islands, Windward Islands, and Tobago ( Chace 1972); Netherlands Antilles ( Westinga and Hoetjes 1981); Panama ( Duffy 1992, 1993, 1996b); Surinam ( Holthuis 1959); Belize Barrier Reef ( Duffy 1993; this study); Brazil ( Coutière 1909; Coelho and Ramos 1972).

Remarks. Z. brooksi is among the most widely reported species of Zuzalpheus , owing to its wide geographic distribution, and often extremely high densities in conspicuous, shallow-water sponges. Yet the discovery of several related species that are morphologically very similar to this species, including Z. bousfieldi ( Chace 1972) and Z. idios new species, suggests that previous records of Z. brooksi from habitats other than its common host Spheciospongia vesparium should be treated with some caution.

Figures

PLATE 1. Zuzalpheus agelas, male. (VIMS 04CBC4301) from Agelas clathrodes, Long Reef, Belize. Zuzalpheus androsi, female (VIMS 03CBC0901) from Hyattella intestinalis, Carrie Bow Cay, Belize. Zuzalpheus bousfieldi, female (VIMS 03CBC1201) from Hyattella intestinalis, Carrie Bow Cay, Belize. Zuzalpheus bousfieldi, male (VIMS 03CBC1202) from Hyattella intestinalis, Carrie Bow Cay, Belize. Zuzalpheus brevifrons, female (VIMS 03CBC3601) from unidentified sponge, Sand Bores, Belize. Zuzalpheus brooksi, female (VIMS 05FK14) from Spheciospongia vesparium, Key Largo, Florida, USA.

FIGURE 11. Zuzalpheus filidigitus (Armstrong 1949). Male holotype 2.4 mm (AMNH 9572): a, anterior region of carapace and cephalic appendages, lateral view (right scaphocerite missing); b, same, dorsal view. Male 2.3 mm (USNM 1019061): c, left minor first pereopod (setal combs on dactyl omitted), lateral view; d, same, tip of dactyl, ventrolateral view; e, same, tip of fixed finger, lateral view; f, left second pereopod, lateral view; g, same, tip of chela with some setae removed, lateral view; h, left third pereopod, lateral view; i, same, detail of distal portion, lateral view. Scale bar = 1.3 mm for a, b, c, f; 1.0 mm for h; and 0.25 mm for d, e, i, g.

FIGURE 12. Zuzalpheus filidigitus (Armstrong 1949). Male 2.4 mm (USNM 1019061): a, abdomen, lateral view. Incomplete moult (VIMS 01CBC0502): b, first pleopod; c, telson and left uropod, dorsal view; d, distolateral corner of left uropod, dorsal view. Scale bar = 1.6 mm for a; 0.41 mm for b; 1.0 mm for c; and 0.31 mm for d.

FIGURE 13. Zuzalpheus idios, n. sp. Allotype ovigerous female 5.1 mm (USNM 1019048): a, anterior region of carapace and cephalic appendages, dorsal view; b, same, lateral view; c, telson and uropods, dorsal view. Scale bar = 1 mm for a, b; and 0.76 mm for c.

FIGURE 14. Zuzalpheus idios, n. sp. Allotype ovigerous female 5.1 mm (USNM 1019048): a, chela of major first pereopod in lateral view; b, same, anterior region alternate lateral view; c, same, dorsal view; d, same, tip of fixed finger, ventral view. Paratype male 4.7 mm (USNM 1019049): e, minor first pereopod, lateral view; f, distal portion of same, alternate lateral view. Scale bar = 1 mm for a, b, c, d; 1.2 mm for e; and, 0.24 mm for f.

FIGURE 16. Zuzalpheus idios, n. sp. Paratype male 4.7 mm (USNM 1019049): a, third pereopod; b, same, detail of distal portion; c, fourth pereopod; d, same, detail of distal portion; e, fifth pereopod; f, detail of distal portion; g, second pereopod. Scale bar = 1 mm for a, c, e, g; and 0.2 mm for b, d, f.