Zuzalpheus paraneptunus ( 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 : 55-57

Zuzalpheus paraneptunus ( Coutière, 1909) n. comb.

( Plate 4 )

Synalpheus paraneptunus, Coutière 1909:86–89 , Fig. 52; Dardeau 1984:92–98, Figs. 47–50 (and synonymy).

Material examined. (1) 1 ovigerous ♀ ( VIMS 01 CBC5504), 3.1 mm, 1 ♂ ( VIMS 01 CBC5505), 2.9 mm, The Pinnacles (Sand Bores) SW of Carrie Bow Cay, Belize, 2 May 2001, in Xestospongia proxima , 2 m.

(2) 1 ovigerous ♀ ( VIMS 01 CBC0504), 4.6 mm, 1 ♂ ( VIMS 01 CBC0503), 4.5 mm, outer ridge at Curlew Cay, 27 April 2001, in Xestospongia proxima , 15–18 m.

(3) 1 ovigerous ♀ ( VIMS 03 CBC5801), 3.4 mm, 1 ♂ ( VIMS 03 CBC5802), 2.8 mm, The Pinnacles (Sand Bores) SW of Carrie Bow Cay, Belize, 28 April 2003, in Pachypellina podatypa , 2 m.

(4) 1 ♀ ( VIMS 94 CBC9201), 2.4 mm , 1 ♂ ( VIMS 94 CBC9203), 2.4 mm, fore-reef slope at Carrie Bow Cay , Belize, 30 August 1994, in Oceanapia sp. , 18 m .

(5) 1 ♀ ( VIMS 96 CBC2001), 3.3 mm , 1 ♂ ( VIMS 96 CBC2002), 3.2 mm, outer ridge at Carrie Bow Cay , Belize, 13 June 1996, in Oceanapia sp. , 17 m .

(6) 1 ovigerous ♀ (98CBC5003), 3.3 mm, 1 ♂ ( VIMS 98 CBC5004), 2.7 mm, outer ridge at Carrie Bow Cay , Belize, 8 December 1998, in Xestospongia cf. subtriangularis , 17 m.

(7) 1 ovigerous ♀ ( VIMS 99 CBC5302), 3.8 mm, 1 ♂ ( VIMS 99 CBC5304), 3.2 mm, outer ridge at Carrie Bow Cay , Belize, 9 December 1999, in unidentified soft white sponge, 17 m.

Diagnosis. Body subcylindrical; carapace smooth, sparsely setose, with pterygostomian corner very obtusely angular, and posterior margin with cardiac notch distinct.. Rostrum clearly narrower than ocular hoods, about as long as ocular hoods, and distally upturned; margins in dorsal view, concave or convex. Orbitorostral process absent. Ocular hoods dorsally convex; in dorsal view, acute, margins concave or convex, separated from rostrum by deep adrostral sinus. Ocular processes present, but not elongated. Ocellary beak in lateral view rodlike. Stylocerite slender; mesial margin slightly concave; tip acute; clearly exceeding distal margin of 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, and with longer ventrolateral spine clearly overreaching tip of stylocerite. Scaphocerite with blade reduced, and with robust, acute lateral spine with lateral margin slightly concave, clearly 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 less than half length of palm; fixed finger reduced, much shorter than dactyl; in ventral view, outer face of fixed finger with an obtuse basal protuberance. Palm of chela with distal superior margin produced into tapering acute spine. Merus, extensor margin strongly convex, with distal angular projection.

Minor pereopod 1 with palm clearly less than two times longer than high; fingers clearly shorter than palm; dactyl with flexor surface excavate, with two distal teeth, subequal in length and oriented perpendicular to long axis of dactyl; transverse dorsal setal combs on extensor surface of dactyl present but reduced to irregular field rather than thick brush; fixed finger with flexor surface excavate, and 2 distinct teeth subequal in length. Extensor margin of merus convex, with distal angular projection.

Pereopod 2 carpus with five segments (rarely four); and equal or shorter than merus.

Pereopod 3 stout; dactyl biunguiculate, with clearly unequal teeth; and extensor tooth wider at base than flexor; merus without movable spines on flexor margin; mesial lamella on coxa present.

Pleura 1 of male with posterior corner weakly produced, or rounded; second pleura of male rounded to obtuse. Pleopod 1 of male with few terminal setae on endopod; second pleopod of male with marginal setae on exopod originating near midpoint; appendix interna on second to fifth male pleopods, present. Telson, space between distal spines more than one third of distal margin; marginal convex lobe present; posterior corners adjacent to spines acute; projections not longer than wide. Anal flaps, perianal setae, and postanal setal brush absent. Uropods with usually two or more more fixed teeth on outer margin of exopod.

Color ( Plate 4 ). Transparent, distal palm and fingers of major chela usually tinged dark brown, varying from dull orange to blue-black; ovaries and eggs bright grass green to bright yellow.

Hosts and ecology. In Belize this species is not very common, but we have collected it from a variety of hosts including Hyattella intestinalis , Oceanapia sp. , Pachypellina podatypa , Xestospongia cf. proxima , at depths ranging from 1– 20 m. Usually, one or a few heterosexual pairs are found in an individual sponge, sometimes with a few juveniles also present. According to Coutière (1909, p. 87), “the eggs give rise to zoëae”.

Distribution. Western Atlantic: Florida Keys, USA (J.E. Duffy, unpublished); Bahamas ( Lemaitre 1984); Cuba (Martínez Iglesias and García Raso 1999); Jamaica ( Coutière, 1909); Puerto Rico ( Schmitt 1935); Gulf of Mexico ( Dardeau 1984); Yucatan peninsula, Leeward Islands, Windward Islands ( Chace 1972); Belize Barrier Reef (this study); Bonaire ( Schmitt 1936); San Blas Islands, Panama ( Duffy 1992); Colombia ( Coutière, 1909).

Remarks. Zuzalpheus paraneptunus is a morphologically distinctive species that is difficult to confuse with any other West Atlantic species. The excavate, spoon-shaped fingers of the minor first chela, together with the sparse field of setae on the dactyl thereof, are unique in this region. Indeed, the reduction of the setal brush on the minor chela dactyl, which is diagnostic for Zuzalpheus , has suggested to several authors that the “gambarelloides group” (herein elevated to genus level as Zuzalpheus ) may not be homogeneous ( Coutière, 1909, Dardeau 1984). Morrison et al. (2004) found strong support for a sister-taxon relationship between Z. paraneptunus and the new species Z. kensleyi (called S. “intermediate” in that publication), described herein, suggesting that Z. paraneptunus is indeed closely related to the other species of Zuzalpheus . Nonetheless, as suggested by Dardeau (1984), the membership and geographic distribution of the new genus will remain somewhat uncertain until a careful phylogenetic comparison can be made with some of the Indo-Pacific species in the Coutièrei (previously Biunguiculatus) group, which share some morphological characteristics with Z. paraneptunus ( Banner and Banner 1975) .

Figures

PLATE 4. Zuzalpheus pandionis, female (VIMS 03CBC1701) from Lissodendoryx sp., Carrie Bow Cay, Belize. Zuzalpheus paraneptunus, female (VIMS 01CBC0704) from Oceanapia sp., Curlew Reef, Belize. Zuzalpheus pectiniger, female (VIMS 05FK1501) from Spheciospongia vesparium, Key Largo, Florida, USA. Zuzalpheus pectiniger, male (VIMS 05FK1502) from Spheciospongia vesparium, Key Largo, Florida, USA. Zuzalpheus regalis, female (VIMS 01CBC02) from Xestospongia cf. subtriangularis, Curlew Reef, Belize. Zuzalpheus ruetzleri, female (VIMS 01CBC6301) from Hymeniacidon caerulea, Sand Bores, Belize.