Zuzalpheus chacei ( Duffy, 1998 ) 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 : 16-18

Zuzalpheus chacei ( Duffy, 1998) n. comb.

( Plate 2 )

Synalpheus chacei Duffy, 1998:389 , Figs. 1–5 (and synonymy); Ríos 2003:53, plate II. Material examined. (1) Holotype ♂ (USNM 282773, VIMS 90CBC3602), 2.4 mm, Carrie Bow Cay, Belize, in Agelas dispar , 3 m.

(2) 1 ♀ (?), 2.4 mm ( VIMS 96 CBC1805) , 27 ♂, 1.7–2.4 mm ( VIMS 96 CBC1806), spur and groove of Carrie Bow Cay , Belize, 14 June 1996, in Agelas dispar , 4 m .

(3) 2 ♀ ( VIMS 90 CBC0203, 90CBC0207), 2.5 mm, 2.4 mm , 6 ♂ ( VIMS 90 CBC0206, 90CBC0217, 90CBC0218, 90CBC0219, 90CBC0220, 90CBC0222), 1.6–2.2 mm, from larger colony, outer ridge at Carrie Bow Cay , Belize, 12 December 1990, in Hymeniacidon amphilecta , 16 m .

(4) 1 ♀ ( VIMS 94 CBC7803), 2.2 mm , 13 ♂ ( VIMS 94 CBC7804 – 94CBC7816), 1.5–2.3 mm, Blue Ground Range , W of Carrie Bow Cay, Belize, 28 August 1994, in Hyattella intestinalis , 3 m .

(5) 1 ♀ ( VIMS 96 CBC3702), 2.7 mm , 32 ♂ ( VIMS 96 CBC3706 – 96CBC3735), 2.3–2.7 mm, outer ridge at Carrie Bow Cay , Belize, 17 June 1996, in Lissodendoryx cf. strongylata , ~ 15 m .

Diagnosis. Body subcylindrical; carapace smooth, sparsely setose, with pterygostomian corner very obtusely angular, and posterior margin with cardiac notch distinct. Rostrum triangular, about as long as, but narrower than, ocular hoods, with slightly upturned tip. Orbitorostral process absent, but convex keel present under rostrum base. Ocular hoods dorsally convex; in dorsal view, bluntly triangular, separated from rostrum by deep adrostral sinus. Ocular process broad and shallow. Ocellary beak triangular in lateral view. Stylocerite stocky; mesial margin slightly concave, occasionally convex; tip blunt; barely reaching midpoint of first segment of antennular peduncle; this latter segment without mesio-ventral tooth, and with 2 basal ventral processes. Basicerite with dorso-lateral corner straight to rounded, longer lateral spine surpassing midpoint of 2 nd segment of antennular peduncle. Scaphocerite blade absent, lateral spine acute, with lateral margin slightly concave, overreaching distal margin of 2 nd segment of antennular peduncle; mesial projection at base of scaphocerite present. Maxilliped 3 with distal circlet of spines on distal segment and without ventrodistal spine on antepenultimate segment.

Major pereopod 1 massive, fingers shorter than half length of palm; fixed finger about as long as dactyl; in ventral view, outer face of fixed finger without protuberance. Palm of chela with distal superior margin produced into prominent but short, blunt tubercle; merus with extensor margin strongly convex, ending in obtuse angle.

Minor pereopod 1 with palm less than 2 times longer than high; fingers shorter than palm; dactyl with flexor margin straight, blade-like, terminating in two strong distal teeth, subequal in length, and parallel to dactyl axis; transverse dorsal setal combs on extensor surface of dactyl very conspicuous, uniquely arranged in 2 longitudinal sets separated by a strip lacking setae; fixed finger with flexor margin straight, blade-like, and terminating in two strong teeth subequal in length; extensor margin of merus slightly convex, ending in a right angle.

Pereopod 2 with carpus 5-segmented, about as long as merus.

Pereopod 3 slender; dactyl biunguiculate, with proximal tooth slightly thicker and straighter than distal one; merus without movable spines on flexor margin; mesial lamella on coxa present. Pereopods 4 and 5 normal.

Pleura 1 of male with posteroventral corner acutely produced into wide hook; pleura 2 of male broadly rounded, occasionally with posterior corner obtuse. Remaining pleura increasingly acute, but still obtuse. Pleopod 1 of male with 3 or 4 terminal setae on endopod; pleopod 2 of male with marginal setae on exopod originating near midpoint; appendix interna present on male pleopods 2–5. Telson, space between posterior marginal spines about one-third width of posterior margin; marginal convex lobe present; posterior corners adjacent to spines obtuse. Anal flaps, perianal setae, and postanal setal brush all absent. Uropods with a single fixed tooth on outer margin of exopod anterior to, and distinctly removed from, thicker and longer movable spine, latter adjacent to smaller internal fixed tooth.

Color ( Plate 2 ). Translucent with a milky wash on the major chela and body; legs and tail fan transparent; distal edges of both of first pair of chelae with a gold to brownish tinge. Sometimes, several red chromato- phores are apparent on the carapace between the eyes. The eggs are yellowish to creamy opaque.

Hosts and ecology. Like Z. regalis and Z. filidigitus , Z. chacei is eusocial and is consistently found in aggregations of tens of indidivuals, usually with a single reproductive female ( Duffy 1998; Duffy et al. 2000). This species has among the wider host ranges of West Atlantic Zuzalpheus species , inhabiting the internal canals of several species of demosponges; in Belize, we have collected it from Agelas dispar , A. clathrodes , Hyattella intestinalis , Hymeniacidon amphilecta ( de Laubenfels, 1936) , and Lissodendoryx strongylata van Soest 1984 . In Caribbean Panama, it has been collected from Agelas dispar , A. clathrodes , Niphates amorpha Wiedenmayer 1977 , and Lissodendoryx colombiensis Zea and van Soest 1986 (J.E. Duffy, unpublished).

Distribution. Western Atlantic: British Virgin Islands ( Chace 1972); San Blas Islands, Panama (as S. bousfieldi , see J.E. Duffy 1992); Belize Barrier Reef (this study).

Figures

FIGURE 1. Schematic drawings of a Zuzalpheus shrimp showing important structures used in taxonomy: a, ovigerous female, lateral view; b, tail fan with left uropod omitted, dorsal view; c, anterior region of carapace with left antennal (A2) and antennular (A1) peduncles, dorsal view.

FIGURE 2. Zuzalpheus brevifrons (Chace 1972). Male 3.2 mm (VIMS 95CBC3501): lateral view of abdomen. Scale bar = 1mm.

FIGURE 3. Zuzalpheus dardeaui, n. sp. Paratype female 9.1 mm (USNM 1019041): a, anterior region of carapace and cephalic appendages, dorsal view; b, same, lateral view. Paratype male 7.6 mm (USNM 1019040): c, abdomen, lateral view. Paratype ovigerous female 9.2 mm (USNM 1019040): d, abdomen, lateral view. Allotype ovigerous female 9.9 mm (USNM 1019039): e, abdomen, lateral view. Paratype male 8.2 mm (VIMS 01CBC7408): f, detail of 4th–6th abdominal pleurae, lateral view. Scale bar = 1 mm for a, b; 2 mm for c, d; 2.5 mm for e; and 1.2 mm for f.

FIGURE 4. Zuzalpheus dardeaui, n. sp. Paratype male 7.6 mm (USNM 1019040): a, major first pereopod, lateral view; b, same, tip of fixed finger, ventral view; c, same, merus, lateral view; d, minor first pereopod, lateral view; e, distal portion of same, alternate lateral view. Paratype ovigerous female 9.2 mm (USNM 1019040): f, distal portion of chela of major first pereopod, lateral view. Paratype female 9.1 mm (USNM 1019041): g, distal portion of chela of major first pereopod, lateral view; h, telson and uropods, dorsal view. Scale bar = 1 mm for a, c, g; 0.66 mm for b; 0.5 mm for d, f, h; and 0.12 mm for e.

FIGURE 5. Zuzalpheus dardeaui, n. sp. Paratype male 7.6 mm (USNM 1019040): a, left third pereopod; b, same, detail of distal portion; c, left fourth pereopod; d, same, detail of distal portion; e, left fifth pereopod; f, same, detail of distal portion; g, left second pereopod; h, same, detail of distal portion. Scale bar = 1 mm for a, c, e, g; 0.25 mm for b, d, f; and 0.5 mm for h.

PLATE 2. Zuzalpheus carpenteri, female (VIMS 04CBC4202) from Agelas clathrodes, Long Reef, Belize. Zuzalpheus carpenteri, male (VIMS 04CBC4201) from Agelas clathrodes, Long Reef, Belize. Zuzalpheus chacei, female (VIMS 01CBC1101) from Lissodendoryx cf. strongylata, Curlew Reef, Belize. Zuzalpheus dardeaui, female (VIMS 01CBC7407) from Lissodendoryx colombiensis, Twin Cays, Belize. Zuzalpheus dardeaui, male (VIMS 01CBC706) from Lissodendoryx colombiensis, Twin Cays, Belize. Zuzalpheus elizabethae, female (VIMS 03CBC0801) from Lissodendoryx sp., Carrie Bow Cay, Belize.