Siphonoecetini Just, 1983

Just, Jean, 2017, A fresh look at the higher classification of the Siphonoecetini Just, 1983 (Crustacea, Amphipoda, Ischyroceridae) 12: with a key to all taxa, Zootaxa 4320 (2), pp. 321-338 : 326-328

Siphonoecetini Just, 1983 , comb. nov.

Siphonoecetini Just, 1983 , by Myers & Lowry, 2003.

Not Siphonoecetini Myers & Lowry, 2003.—Error in Krapp-Schickel (2013).

Type genus. Siphonoecetes Krøyer, 1845 .

Diagnosis. Antenna 1 in male and female shorter than antenna 2, peduncle article 1 not inflated, without accessory flagellum. Antenna 2 pediform, articles 3–5 inflated compared to antenna 1 ( Fig. 2 C 1 ). Mandible palp short, with 2 (occasionally 1) articles, article 2 vestigial ( Fig. 2 C2a–b ). Gnathopod 1 propodus simple ( Fig. 2 C 3 ). Gnathopod 2 oval or subchelate ( Fig. 2 C 4 1 or 2), carpus shorter than propodus, similar in both sexes. Coxae 1–4 about as long as wide or longer. Pereopods 5 and 6 similar, much shorter than slender pereopod 7 ( Fig. 2 C 5a), propodus embedded in anterodistal margin of kidney-shaped carpus; dactyli of pereopods 5–7 backward pointing. Urosomites 1–2 free, urosomite 3 proximal part normally telescoped under 2 in dorsal view. Uropod 2 with 1 or 2 rami, or uropod absent; uropod 3, with single, short ramus or ramus absent, ( Fig. 3 C1–3 ). Telson about as long as broad, entire, with 2 distolateral spine patches ( Fig. 2 C 6), proximal margin hidden under urosomite 2 distal margin in dorsal view, or fused with dorsally visible urosomite 3 ( Fig. 3 C 2 or 3).

Component taxa. Bubocorophiina subtribe nov., Caribboecetina subtribe nov., Siphonoecetina Just, 1983, subtribe. nov.

Figures

FIGURE 1. A. The relationship among the proposed tribes in the subfamily Ischyrocerinae based on clades identified by Lowry & Berents (1996). B. Subtribes in tribe Siphonoecetini as established here. (Illustrated: A, Cephaloecetes schioettei Just, 2017, in abode; B, Rhinoecetes coclearis Just, 2012 a, abode aggregation).

FIGURE 2. A, Ericthonini; B, Cerapodini; C, Siphonoecetini. 1, antennae; 2, mandibles; 3, gnathopod 1; 4, gnathopod 2 (c 1 simple and c 2 subchelate forms); 5 a, pereopods 5 – 7; 5 b, pereonite 5 with coxa; 6, telson with uropod 3. (A 2 from Lowry & Berents 1996; A 6 from Lowry & Berents 2005; B 2 from Krapp-Schickel 2013.)

FIGURE 3. A, coxal plate 2 (and 3); B, distal parts of pereopod 5 (and 6); C 1, Siphonoecetina urosome, C 2 and C 3, Bubocorophina urosomes, C 4, Caribboecetina urosome; D, sternal papillae on pereonite 7. E, antenna 2 flagellum, 1 – 3 articles 1 – 3; F, uropod 1, vv ventral view, lv lateral view, (refers to keys below).

FIGURE 4. A, lateral and dorsal views of heads of Rhinoecetes spp.; B, lateral view of head with pseudorostrum; C, complexly lobate lower lip; D, simple lower lip; E, pereopod 7; F, rami of uropod 1 of Rhinoecetes spp., G, uropod 3 with rounded ramus; H, natatory antenna 2 of Australoecetes sellicki.