Stenothoe verrucosa, Krapp-Schickel, 2009

Krapp-Schickel, T., 2009, New and poorly described stenothoids (Crustacea, Amphipoda) from the Pacific Ocean., Memoirs of Museum Victoria 66 (1), pp. 95-116 : 98

Stenothoe verrucosa n.sp.

Figs. 3 , 4

Holotype: male 3.5mm; from „Danske Expedition til Kei Oerne” by T. Mortensen, 1922; 15m sand and Acanthogorgia ; slide ZMUC CRU-20185 .

Type locality: Kai (or Kei) Islands (= Nuhu Evav, Tanat Evav), E-Banda-Sea, SE Indonesia, province Maluku (see also Mortensen, 1923).

Etymology: „Warty“ is in Latin „verrucosus“; used as an adjective, indicating the very special structure of the second antenna.

Description. Based on male, 3.5 mm.

Head. Eyes normal size, roundish. Antenna 1 longer than head and peraeonites 1–4, longer than antenna 2; peduncular article 2 longer than article 1; flagellum with 22 articles; accessory flagellum absent. Antenna 2 peduncle article 4 shorter than article 5 and thicker; article 5 with 5 humps or „warts“ on the inner margin; flagellum article 1 thickened proximally and distally next to the articulations on the inner side; obviously these second antennae are used to grip or hold on the host, as they are always kept symmetrically with these humps showing to the antenna of the other side.

Mouthparts. Mandible palp absent, molar absent. Maxilla 1 palp 2–articulate. Maxilliped inner plate reaching along 1/3 of ischium, outer plate absent.

Peraeon. Gnathopods 1–2 dissimilar in size and shape. Gnathopod 1 subchelate; merus very much enlarged, produced distally, surpassing carpus; carpus triangular, much longer than wide, more than 2x as long as wide; propodus about 2x as long as broad, medially widened, palm defined by obtuse corner. Coxa 2 anterior margin rounded, posterior one straight, distally with rounded corner. Gnathopod 2 subchelate, carpus shorter than wide, cup-shaped; propodus distally narrowing, palm with 4–5 small humps, no palmar corner; dactylus reaching along full length of propodus, inner margin beset with many short setae. Coxa 3 distally with stridulation ridge, posterior margin excavated. Peraeopod 5 basis linear, merus widened and distally also shortly lengthened, reaching about 1/2 along carpus. P 6, 7 basis fully expanded; merus distal expansion reaching about 1/2 length of carpus; dactylus subequal to half propodus.

Pleon. Epimeron 3 posteroventral corner subquadrate/ rounded. Urosomites free. Uropod 1 peduncle without distoventral spine,beset with many short robust setae;subequal rami shorter than peduncle. U 2 innerramisomewhatshorter than outer ones. U 3 with peduncle and single ramus, which is shorter than peduncle, 2 articulate, article 2 shorter than article 1; ramus article 1 each with 1 robust seta. Telson laminar, with 2 dorsolateral robust setae, apically subacute.

Female unknown.

Habitat. Marine; among the gorgonacean Acanthogorgia . On sand, 15 m.

Distribution: Indonesia, Pacific Ocean.

Remarks. This species shares the very unusual and characteristic humps or „warts“ on the second antennae with Stenothoe garpoorea n.sp., which was found in the same habitat; but in the latter these humps are not on the last peduncular and first flagellum article, but exclusively on the flagellum.

Figures

Figure 3: Stenothoe verrucosa n.sp.: holotype male 3.5mm, SE Indonesia.

Figure 4: Stenothoe verrucosa n.sp.: holotype male 3.5mm, SE Indonesia.