Spaniomolgus dentatus, Conradi, Mercedes, Bandera, Eugenia, Mudrova, Sofya V. & Viatcheslav N. Ivanenko,, 2018

Conradi, Mercedes, Bandera, Eugenia, Mudrova, Sofya V. & Viatcheslav N. Ivanenko,, 2018, Five new coexisting species of copepod crustaceans of the genus Spaniomolgus (Poecilostomatoida: Rhynchomolgidae), symbionts of the stony coral Stylophorapistillata (Scleractinia), ZooKeys 791, pp. 71-95 : 76-78

Spaniomolgus dentatus sp. n. Fig. 5

Type locality.

Saudi Arabian Red Sea, reef near Thuwal, 22°03'48.5"N, 38°45'51.2"E.

Material examined.

1 ♀ holotype (ZMMU Me-1213) and 1 ♀ paratype (ZMMU Me-1214) from Stylophora pistillata (morphotype S. danae ) (KAUST SA2013-31) collected at 28 m depth.

Etymology.

The specific name from the Latin dentatus , refers to the denticulated margin of the maxillipedal claw.

Description.

Adult female.

Body cyclopiform, with oval cephalothorax and cylindrical urosome (Fig. 5a). Body length 750 µm and maximum width 390 µm. Prosome comprising cephalothorax and three free pedigerous somites. Second and third pedigerous somites with slightly rectangular epimeral areas. Fourth pedigerous somite smaller than preceding ones, its epimeral areas much less expanded.

Urosome 5-segmented, comprising fifth pedigerous somite, genital double-somite and three free abdominal somites (Fig. 6b). Leg 5-bearing somite wider than long. Genital double-somite (Fig. 5b) slightly longer than wide (95 × 83 µm); lateral margins nearly parallel. Paired genital apertures bipartite, each comprising ventrolateral copulatory pore and dorsolateral gonopore (oviduct opening). Each genital area with two minute spiniform elements (Fig. 5b). Egg sac unknown. Three postgenital somites 55 × 83, 53 × 72 and 39 × 67 μm from anterior to posterior.

Caudal rami (Fig. 5b) elongated, 108 × 25 µm, 4.3 times as long as wide. With six setae; all setae relatively short and naked. Outer lateral seta 44 µm, outermost terminal seta 41 µm, innermost terminal seta 33 µm. Two median terminal setae broadened, 72 µm (outer) and 66 µm (inner) in length. Dorsal seta 39 µm.

Antennule, mandible, maxillule, maxilla and armature formula for legs 1-4 as for Spaniomolgus globus sp. n.

Antenna (Fig. 5c) 3-segmented; first segment 53 µm long with small terminal hyaline seta; second segment 68 µm long with seta medially; third segment 60 µm long with three hyaline setae medially and two apical hyaline setae, small recurved terminal claw 24 µm long. Second and third segments measured along inner margin subequal in length.

Maxilliped (Fig. 5d) 3-segmented. First segment unarmed; second segment slightly elongated, with two naked inner setae; third segment claw-like, denticulate distally, with two setae medially.

Leg 4 (Fig. 5e) with 3-segmented exopod and 2-segmented endopod. Inner coxal seta and outer basal seta naked. Endopod reaching beyond middle of third exopodal segment; second segment with two apical spines unequal in length, outer 30 µm long, inner 50 µm long, the latter spines with hyaline and weakly serrated margins. Outer spines of exopod with barbed lamellae.

Fifth Sixth leg (Fig. 5b) with protopod incorporated into somite; outer basal seta not observed. Free segment long, slender and recurved, 4.2 times as long as wide, bearing two apical setae unequal in length, inner most about twice as long as outer one.

Sixth leg (arrowed in Fig. 5b) represented by two very small articulated projections near attachment of eggs sacs.

Male unknown.