Leucothoe ubouhu, 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 : 25-30

Leucothoe ubouhu n.sp.

Figures 15–18 ; 22a–b

Holotype. Male holotype “A,” 9.03 mm, YPM 38656: JDT Bel 03/12A— 6Dec03; Co Cat Cay, Pelican Cays, Belize; N 16º39.527’ x W 88º12.032’; patch reef, in the sponge Spongia officinalis subsp. o bliqua, 1–15m; J.D. Thomas and K.N. Klebba, collectors.

Paratypes. Female paratype “B,” 7.78 mm, YPM 38657: JDT Bel 03/12A— 16Dec03; Co Cat Cay, Pelican Cays, Belize; N 16º39.527’ x W 88º12.032’; patch reef, in the sponge Spongia officinalis subsp. o bliqua, 1–15m; J.D. Thomas and K.N. Klebba, collectors.

Other material examined. YPM 38658: 20June78; Loggerhead Key, Florida, U.S.A.; French Wreck; N 24º 37.957 x W 82º56.012’; host unknown, 3–15m; J.D. Thomas, collector.

Diagnosis. Head: anterior margin angular, anteroventral margin with slight concavity. Gnathopod 1: basis, anterior margin with 7 short setae, propodus, posteromedial margin with three short submarginal setae, dactyl elongate. Gnathopod 2: propodus, mediofacial setal row reaching 0.66 of propodus, secondary mediofacial row with four setae, medial surface of palm with row of seven submarginal setae. Mandible: palp article 2 with 16–17 setae.

Description of male holotype “A”. Ratios of antennae 1 and 2, 0.38 and 0.29 X body length; relative lengths of antennae 1 and 2, 1.00:0.78, flagella 14 and 7-segmented. Anterior margin of head angular, anteroventral margin with slight concavity; mid-ventral keel, anterior margin vertical, slightly exceeding anterior margin of head, ventral margin broadly rounded. Coxae 1–4, width ratios 1.00:1.28:0.96:1.52; coxae 5–6 bilobed; coxa 7 reduced, ovate.

Upper lip asymmetrically lobate, anterior margin setose. Mandibles, lacking molar; palp 3-articulate, ratio of articles 1–3, 1.00:3.30:1.20; article 2 with 10 anterior, two posterior, and four apical setae; article 3 with two apical setae; incisors strongly toothed. Left mandible, lacinia mobilis large, strongly toothed; 11 raker spines. Right mandible, lacinia mobilis a small flake; 14 raker spines. Lower lip, inner lobes fused; outer lobes with wide gape, anterior margin intermittently setose. Maxilla 1, palp 2-articulate with four apical setae; outer plate with seven spines and four basal setae. Maxilla 2, inner plate with 10 medial marginal and 10–11 facial setae; outer plate with four apical and 11 lateral setae. Maxilliped, inner and outer plates reduced; inner plates fused, apical lobes each with three stout spine-setae, apicomedial margin with projection; outer plate with four apicolateral setae; palp 3-articulate; palp article 1 apical and apicolateral margins with approximately 14 serrate setae; article 4 anteromedial margin with dense covering of short pubescent setae.

Gnathopod 1, coxa anteroventral margin produced with two small serrations, ventral margin straight, posteroventral margin rounded; basis slightly expanded, anterior margin with seven short setae, posterior margin setae lacking; carpal lobe, thin, geniculate, LW 7.33, anterior margin grooved with widely spaced short setae, each margin bordered by six-seven rows of denticles, lateral margin with three short setae; propodus, posterior margin serrate, lateral margin with eight long and 12–13 short setae; dactyl long, smooth, recurved, reaching 0.51 of propodus. Gnathopod 2, coxa elongate, LW 0.88, anterior, ventral, and posterior margins smooth, posteroventral corner lacking serrations; basis linear, anterior margin with six short setae, posterior margin bare; carpal lobe distal margin slightly expanded and oblique, strongly serrate with approximately 10 serrations, with short apical setae, reaching 0.52 of propodus, medial margin setose; propodus, palm linear with three strong projections near insertion of dactyl, medial margin with seven submarginal setae, primary mediofacial setal row reaching 0.66 of propodus, secondary mediofacial row with four setae; dactyl long, recurved, reaching 0.52 of propodus.

Pereopod 3, coxa reduced, tongue-shaped, LW 1.18, anterior margin straight, ventral margin convex, posterior margin rounded. Pereopod 4, coxa anterior margin rounded, ventral margin convex, tapering posteriorly, posterior margin excavate. Pereopods 5–7, coxa 5–6 bilobed; coxa 7 small, ventrally convex; pereopods 5–7 bases, LW 1.26:1.24:1.22, posterior margin of pereopod 5 smooth, posterior margins of pereopods 6–7 minutely serrate.

Epimera 1–3, ventral setae 0:4:0, respectively; epimera 3, posteroventral margin broadly rounded. Uropods 1–3, relative lengths 1.00:0.71:0.92; relative lengths of peduncles 1–3, 1.00:0.60:1.16. Uropods 1–3, medial margins of outer rami lacking setae. Uropod 1, peduncle 0.92 X rami length, with three medial and six lateral marginal setae; outer ramus 0.96 X inner ramus; inner ramus with eight medial and nine lateral marginal setae; outer ramus with 11 lateral marginal setae. Uropod 2 shortened, peduncle 0.96 X rami, with one medial apical seta and two lateral marginal setae; outer ramus 0.81 X inner ramus length, inner ramus with six medial and five lateral marginal setae; outer ramus with six lateral marginal setae. Uropod 3, peduncle 1.40 X rami length, with one apicomedial and nine lateral marginal setae; outer ramus reaching 0.97 of inner ramus; inner ramus with three medial and five lateral marginal setae; outer ramus with five lateral marginal setae. Telson LW 2.59, apical margin tridentate with two apical setae.

Description of female paratype “B”. Similar to male in all aspects except the following: Gnathopod 1, basis, posterior margin with slight proximal inflation, posterodistal margin with 10 long setae, anterior margin with nine; gnathopod 2, carpus, distally oblique, with six to eight apical setae; basis, anterior margin with 11 scattered long and short setae, anteroventral corner with tuft of four short setae, posterodistal margin with three setae.

Etymology. Gari’funa term for “island.”

Relationship. Leucothoe ubouhu most closely resembles Leucothoe barana in the angular margin of the head. The oblique margin of the carpus on gnathopod 2 and the extremely long dactyl of gnathopod 1 of L. ubouhu resembles Leucothoe saron . Females of L. ubouhu are distinct among Western Atlantic species in having a tuft of numerous long posterodistal setae on basis of gnathopod 1.

Ecology. In Belize, L. ubouhu was found in the sponges Cliona [ Anthosigmella ] varians , Hyrtios sp., Lissodendoryx isodictyalis , Mycale laxissima , and Spongia officinalis subsp. o bliqua. The host is unknown in Florida.

Distribution. Western Atlantic, Belize to Florida, 2–15 meters.

Figures

FIGURE 15. Leucothoe ubouhu n. sp. male holotype “ A, ” 9.03 mm; female paratype “ B, ” 7.78 mm.

FIGURE 16. Leucothoe ubouhu n. sp. male holotype “ A, ” 9.03 mm; female paratype “ B, ” 7.78 mm.

FIGURE 17. Leucothoe ubouhu n. sp. male holotype “ A, ” 9.03 mm; female paratype “ B, ” 7.78 mm.

FIGURE 18. Leucothoe ubouhu n. sp. male holotype “ A, ” 9.03 mm.