Leucothoe garifunae, Thomas, James Darwin & Klebba, Kristine N., 2007

Thomas, James Darwin & Klebba, Kristine N., 2007, New species and host associations of commensal leucothoid amphipods from coral reefs in Florida and Belize (Crustacea: Amphipoda), Zootaxa 1494, pp. 1-44 : 15-16

Leucothoe garifunae n.sp.

Figures 8–10 ; 14a–b

Holotype. Male “A,” 5.17 mm, YPM 38646: JDT Bel—03/08A, 10Dec03; Spruce Cay, south of Wee Wee Cay, Belize; N 16º44.119’ x W 88º08.544’; patch reef, in the sponge Iotrochota birotulata , 3m; J.D. Thomas and K.N. Klebba, collectors.

Paratypes. Female “B,” 5.94 mm, YPM 38647: JDT Bel 03/08A— 10Dec03; Spruce Cay, south of Wee Wee Key, Belize; N 16º44.119’ x W 88º08.544’; patch reef, in the sponge Iotrochota birotulata , 3m; J.D. Thomas and K.N. Klebba, collectors.

Other material examined. YPM 38648: 20May98; Boynton Beach, Florida, U.S. A; N 26º29.029’ W 80º04.002’; inlet, in Holopsamma helwigii , 1–4m; Martin Thiel, collector.

Diagnosis. Head: anterior margin with angular projection. Mid-ventral keel: steep, projecting beyond head margin. Gnathopod 2: anterior margin of basis with 30–40 long setae; propodus, primary mediofacial setal row reaching 0.87 of propodus, inner margin of palm with linear row of numerous short submarginal setae. Telson: apically rounded.

Description of male holotype “A”. Ratios of antennae 1 and 2, 0.31 and 0.28 X body length; relative lengths of antennae 1 and 2, 1.00:0.90, flagella 18 and 8-segmented. Mid-anterior margin of head with angular projection; mid-ventral keel pronounced, anterior margin oblique, antero-ventral margin sharp, ventral margin convex. Coxae 1–4, width ratios 1.00:1.22:1.00:1.65; coxae 5–6 bilobed; coxa 7 reduced, ovate.

Upper lip asymmetrically lobate, non-lobate margin setose. Mandibles lacking molar; palp 3-articulate, ratio of articles 1–3, 1.00:2.90:2.00; article 2 with 15 posterior setae; article 3 with two apical setae; incisors weakly dentate. Left mandible, lacinia mobilis large, toothed; 11 raker spines. Right mandible, lacinia mobilis a small flake; 11 raker spines. Lower lip, inner lobes fused; outer lobes with moderate gape, anterior margins continually setose. Maxilla 1, palp 2-articulate with four apical setae, outer plate with eight spines. Maxilla 2, inner plate with five stout medial setae, apical margin with numerous small setae and 11 short facial setae; outer plate with three long stout apicomedial setae, remaining apical and lateral margins with row of facial setae. Maxilliped, inner and outer plates reduced; inner plate fused, apical lobes with three apical and several long setae; outer plate with few marginal setae; palp 3-articulate, palp article 1 apical and apicolateral margins with several setae; article 4 anteromedial margin with dense covering of short pubescent setae.

Gnathopod 1, coxa anteroventral corner produced with 2 small notches, ventral margin smooth, posteroventral margin quadrate; basis linear, anterior margin with nine widely spaced short setae, posterior margin lacking setae; carpal lobe, LW 4.86, anterior margin with thin groove, lined with numerous bristle-like setae, mid-posterior margin with three short setae; propodus, posterior margin finely dentate, lateral margin with five stout setae, medial margin with numerous alternating short and medium length setae; dactyl long, reaching 0.41 of propodus. Gnathopod 2, coxa sub-rectangular, LW 1.05, anterior margin straight, ventral margin slightly produced, quadrate, with numerous short submarginal setae, posterior margin straight, remainder of coxa with numerous short scattered facial setae (not illustrated); basis linear, anterior margin with 35–40 long setae, posterior margin lacking setae; carpal lobe, distal margin transverse with four large serrations, reaching 0.61 of propodus, medial margin setose, followed by a brush of baleen-like, flattened setae; propodus, palm obliquely convex with two small medial projections near insertion of dactyl, medial posterior margin with 30– 40 short submarginal setae with secondary tufts of three and four setae respectively, primary mediofacial setal row reaching 0.87 of propodus, secondary mediofacial row lacking; dactyl strong, recurved, reaching 0.70 of propodus.

Pereopod 3, coxa narrow, LW 1.41, anterior margin straight, smooth, ventral margin convex, posterior margin rounded, smooth; pereopod 4, coxa anterior margin straight, ventral margin rounded, posterior margin tapered. Pereopods 5–7 coxae 5–6 bilobed; coxa 7 small, ventrally convex; pereopods 5–7 bases of normal proportions, LW 1.23:1.24:1.22, posterior margins smooth.

Epimera 1–3, lacking ventral setae; epimera 3, posteroventral margin broadly truncate. Uropods 1–3, relative lengths 1.00:0.75:0.91; relative lengths of peduncles 1–3, 1.00:0.78:1.35. Uropod 1, peduncle 1.14 X rami length, with zero medial and four lateral marginal setae; outer ramus 0.73 X inner ramus; inner ramus with zero medial and six lateral marginal setae; outer ramus with five medial and six lateral marginal setae. Uropod 2 shortened, peduncle 0.71 X rami length, with single distomedial spine; outer ramus 0.68 X inner ramus; inner ramus with four medial and five lateral marginal setae; outer ramus with zero marginal and one midapical seta. Uropod 3, peduncle subequal to rami in length, with zero medial and six lateral marginal setae; outer ramus subequal to inner ramus; inner ramus with three medial and four lateral marginal setae; outer ramus with three medial and five lateral marginal setae. Telson, LW 2.60, apical margin evenly rounded with two apical setae.

Description of female paratype “B”. Similar to male in all aspects except gnathopod 2, carpal lobe lacking thick, blunt apical seta: propodus, medial margin of palm with 12 longer setae versus 30+ shorter setae in males.

Etymology. Named in honor of the Gari’funa culture of Central America.

Relationship. Leucothoe garifunae resembles Leucothoe barana in the angle of the head and the prominent mid-ventral keel. However, L. garifunae is readily distinguished by differences in gnathopod 2, including the setose anterior margin of the basis, the long wiry setal tufts on the medial carpal surface, and the more numerous row of postero-marginal setae on the propodus. L. garifunae also differs from L. barana in having smooth posterior margins on pereopods 5–7 and in the rounded versus tridentate condition of the telson.

Ecology. Inhabits the interior canals of the sponges Iotrochota birotulata , Pseudoceratina crassa , and Leucetta imperbis in Belize, and Holopsamma helwigii in Florida.

Distribution. Western Atlantic, Belize to Florida, 1–4 meters.

Figures

FIGURE 8. Leucothoe garifunae n. sp. male holotype “ A, ” 5.17 mm.

FIGURE 9. Leucothoe garifunae n. sp. male holotype “ A, ” 5.17 mm; female paratype “ B, ” 5.94 mm.

FIGURE 10. Leucothoe garifunae n. sp. male holotype “ A, ” 5.17 mm.