Rhinoecetes, 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 : 334-335

F Rhinoecetes

1. Mid-anterior head depression deep, with large ‘brows’ overhanging antenna 1 bases either side of depression ( Fig. 4 A 1 ).. 2 - Mid-anterior head depression moderate to weak; brows short ( Fig. 4 A 2 )......................................... 3 2. Rostrum straight; uropod 2 ramus reaching beyond ramus uropod 3 with nearly its entire length..... R. robustus Just, 1983 - Rostrum sickle-shaped; uropod 2 ramus reaching beyond ramus uropod 3 with about one third its length.................

................................................................................. R. rhinoceros Just, 2012a - Rostrum scythe-shaped; uropod 2 ramus barely reaching ramus uropod 3...................... R. dinoceros Just, 2012a 3. Rostrum in dorsal view slender, elongate, pointed, longer than wide at base....................................... 4 - Rostrum in dorsal view triangular, as long as wide at base................................ R. brevirostris Just, 2012a

4. Ventral apical corona of uropod 1 peduncle strongly denticulate................................ R. anneae Just, 2012b

- Ventral apical corona of uropod 1 peduncle with fine setules (fimbriate).......................................... 5

5. Uropod 1 outer ramus with dorsolateral row of robust setae, with dense spinules on lateral margin; uropod 1 inner ramus lateral margin heavily spinose; uropod 2 ramus with dorsolateral row of small robust setae; uropod 3 ramus with distomedial robust seta......................................................... R. spinicaudus Kodama, Ohtsuchi & Kon (2016)

- Uropod 1 outer ramus with dorsolateral row of robust setae, lateral margin unarmed; uropod 1 inner ramus lateral margin unarmed; uropod 2 ramus without dorsolateral robust setae; uropod 3 ramus without distomedial robust seta............ 6

6. Uropod 1 outer ramus broad, twisted spoon-shaped ( Fig. 4 Fa), with dense lateral row of robust setae, dorsal surface with many small simple setae................................................................... R. coclearis Just, 2012a

- Uropod 1 outer ramus slender, slightly curved but not spoon-shaped, with few lateral robust setae and no dorsal simple setae ( Fig. 4 Fb).......................................................................................... 7

7. Eye lobes truncate in lateral view; uropod 2 ramus not reaching beyond ramus uropod 3........ R. meridianus Just, 2012a

- Eye lobes rounded in lateral view; uropod 2 ramus reaching beyond ramus uropod 3 with about half its length.......................................................................................... R. albomaculosus Just, 2012a

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 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.