Family Melitidae Bousfield, 1973

Dulichiella beluu sp. nov. (Figs. 18, 19)

Type material. Holotype male (OUMNH.ZC. 2002-24 -160), 4.0 mm, Beluu Lukes Reef, eastern side, from coralline algae encrusted with filamentous sponge, - 6 m depth; 07°17.530'N, 134°30.870'E; leg. S. De Grave & C. Burras, 20 May 2002. Paratypes. 9 males, 7 females (OUMNH.ZC. 2002-24 -161), same data as holotype .

Additional material. 1 female 5.7 mm, Beluu Lukes Reef, eastern side, from Spondylus sp. (Mollusca: Spondylidae), - 10 m depth; 07°17.530'N, 134°30.870'E; leg. S. De Grave & C. Burras, 20 May 2002; 9 male, 13 female, 1 juv. Siaes Corner, from Chondrilla sp. (Porifera: Chondrillidae), - 30 m deep; 07°18.756'N, 134°13.515'E; leg. S. De Grave & C. Burras, 22 May 2002; 1 female, Beluu Lukes Reef, reef slope, from Pericharax heteroraphus Polejaéff, 1884 (Porifera: Leucettidae), - 15m depth; 07°17.530'N, 134°30.870'E; leg. S. De Grave & C. Burras, 27 May 2002; 6 males, 5 females, Beluu Lukes Reef, reef slope, from Leucetta sp. 2 (Porifera: Leucettidae), - 15m depth; 07°17.530'N, 134°30.870'E; leg. S. De Grave & C. Burras, 27 May 2002; 1 male, Siaes Tunnel, inside tunnel, from Leucetta sp. (Porifera: Leucettidae), - 35m depth; 07°18.690'N, 134°13.605'E; leg. S. De Grave & P. Colin, 31 May 2002; 2 males, 1 female, Outside Malakal Harbour, light trap sample, 190 feet deep; 07°16.366'N, 134°27.906'E; leg. S. De Grave & C. Burras, night 1–2 June 2002.

Type locality. Beluu Lukes Reef, Palau, 07°17.530'N, 134°30.870'E.

Etymology. Named after the type locality.

Description. Based on male holotype, 4.0 mm.

Head. Eyes round; lateral cephalic lobe broad, truncated, anteroventral corner with slender seta. Antenna 1 peduncular article 1 shorter than article 2, with 3 robust setae along posterior margin. Antenna 2 peduncular article 2 cone gland almost reaching to end of peduncular article 3; article 4 subequal to article 5. Mandible article 2 subequal with article 3.

Pereon. Gnathopod 1 coxa anteroventral corner not produced, anterior margin straight, posteroventral corner notch present (minute); palm convex, weakly defined by posterodistal corner. Gnathopod 2 coxa posteroventral corner notch absent; left larger gnathopod propodus distolateral crown with 3 rounded spines, palm sinusoidal, posterodistal corner produced, rounded, dactylus fitting against corner; dactylus apically blunt; right smaller gnathopod merus with sharp posteroventral spine; palm straight, posterodistal corner with robust seta. Pereopods 3–7 dactylar unguis anterior margin with accessory spine. Pereopods 6–7 basis, merus, carpus and propodus without bunches of long slender setae. Pereopod 6 basis posterior margin substraight; dactylar unguis anterior margin with accessory spine. Pereopod 7 basis posterior margin sinuous.

Pleon. Pleonites/urosomites dorsal spine formula (7–7–7–5–6–2). Pleonites 1–3 with sparse dorsal setae. Epimera 1–2 posteroventral corner with acute spine. Epimeron 3 posteroventral margin smooth, corner produced with well developed spine. Uropod 3 outer ramus very long, about 2 x peduncle. Telson with dorsal robust setae.

Female (sexually dimorphic characters). Gnathopod 2 subequal in size, similar to smaller gnathopod 2 of male; palm substraight; dactylus posterior margin crenulate. Pereopod 7 basis expanded, posterior margin convex and tapering distally.

Habitat. Coralline algae and sponges.

Remarks. There are currently 18 species of Dulichiella described from world seas (see Lowry & Springthorpe 2007, Tomikawa & Komatsu 2012, Paz-Ríos & Ardisson 2014, Alves, Johnsson & Senna 2014 (with key to world species)). Only six species have male gnathopod 2 (left) with three spines on the propodus distolateral crown, D. anisochir (Krøyer, 1845), D. tulear Lowry & Springthorpe, 2007, D. terminos Lowry & Springthorpe, 2007, D. oahu Lowry & Springthorpe, 2007, D. australis (Haswell, 1879) and D. spinosa Stout, 1912, but the spines of D. terminos are acute. Of the remaining five species, D. anisochir and D. tulear have a serrate epimeron 3 posterior margin, D. oahu has two accessory spines on the anterior margins of the dactylar ungues of pereopods 3 to 7 and D.

australis has bunches of long setae on pereopods 6 to 7 merus to propodus. Dulichiella beluu sp. nov is most similar to D. spinosa from California but that species has a pleosome/urosome dorsal spine formulae of 9–9–7–5– 4–2, whereas in D. beluu sp. nov it is 7–7–7–5–6–2. It is also a much smaller species (4.0 mm in D. beluu sp. nov. whereas D. spinosa is 7.3–12.5 mm).

Distribution. Known only from Palau.