Alexandrella

Serejo, C. S., 2014, A new species of Stilipedidae (Amphipoda: Senticaudata) from the South Mid- Atlantic Ridge, Zootaxa 3852 (1), pp. 133-140 : 139

Key to the species of Alexandrella

(modified from Berge & Vader 2005)

1. Pereonite 7 dorsally with a strong pointed tooth, mandibular incisors smooth........ Alexandrella australis ( Chilton, 1912)

– Pereonite 7 dorsally smooth, mandibular incisors fully or partly toothed......................................... 2

2. Gnathopods 1 and 2 subchelate........................................................................... 3

– Gnathopods 1 and 2 simple.............................................................................. 4

3. Maxilla 1 outer plate with 26 setal teeth; gnathopods 1–2 lacking facial setae; pleonites 1–2 dorsally with weak ridge, pleonite 3 with low rounded tooth...................................... Alexandrella subchelata Holman and Watling, 1983

– Maxilla 1 outer plate with 40–45 setal teeth; gnathopods 1–2 densely setose; pleonites 1–3 dorsally with a well developed pointed tooth................................................................... Alexandrella setosa sp. nov.

4. Pleonites 1–3 strongly toothed, female pereopod 1 with oostegite................................................ 5

– Pleonites 1–3 weakly toothed, female pereopod 1 without oostegite.............................................. 6

5. Right mandible with lacinia mobilis reduced to a simple tooth............. Alexandrella mandibulata Berge & Vader, 2005

– Right mandible with lacinia mobilis broad and toothed, but smaller than left one... Alexandrella martae Berge & Vader, 2005

6. Mandibular incisors not toothed along the entire margin, antennae subequal.......... Alexandrella dentata Chevreux, 1912

– Mandibular incisors toothed along the entire margin, antenna 1 shorter than antenna 2......................................................................................... Alexandrella inermis Bellan-Santini & Ledoyer, 1986