Aeginella corallina Zettler & Freiwald & Guerra-García 2018, sp. nov.
Creators: name: Zettler, Michael L.
name: Freiwald, André
name: Guerra-García, José M.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Caprellidae
Aeginella
Aeginella corallina

description: Aeginella corallina sp. nov.
(Figs 2–6)
Type material. Holotype, mature male, 8.9 mm (used for description and drawings of lateral view, antennae, gnathopods, mouthparts, pereiopods 3–7 and abdomen) (vial: ZMB 31309), Scary mound at 374–375 m water depth at 9.82286°S and 12.77381°E, South Atlantic off Angola, associated to hexactinellid sponges (Sympagella sp. and Aphrocallistes sp.) within a Lophelia pertusa gallery, leg. 22nd January 2016.
Paratype “1”, mature female, 7.3 mm (used for description and drawings of lateral view, antennae, gnathopods, mouthparts, pereiopods 3–7 and abdomen) (vial: ZMB 31310), collected together with the holotype.
Paratype “2”, immature male, 6.2 mm (vial: ZMB 31311), part of the bulk from ROV dive and could not be associated to a specific subsample, same data as holotype.
Paratype “3”, mature male, 8.6 mm (vial: ZMB 31312), Valentine Mound at 500 m water depth at 9.72833°S and 12.71460°E, South Atlantic off Angola, associated to a hydroid which was attached to a dead Madrepora branch, 17th January 2016.
Type locality. Scary Mound at 374–375 m water depth at 9.82286°S and 12.77381°E, South Atlantic off Angola.
Diagnosis. Head with a dorsal acute projection. Pereonite 1 smooth. Pereonite 2 with a pair of dorsal acute projections anteriorly, one projection distally, and lateral acute projections (one in each side) near the coxa of gnathopod 2. Basis and ischium of gnathopod 2 with a distal projection. Propodus of gnathopod 2 very setose in males, provided with one proximal projection and 2 large distal projections. Distal article of the mandibular palp with 4 or 5 setae.
Etymology. The species is named with reference to the cold-water corals habitat in which it was found.
Description. Holotype male (8.9 mm).
Lateral view (Figs 2 and 3). Head with dorsal acute projection. Pereonite 1 lacking projections. Pereonite 2 with a pair of dorsal acute projections anteriorly, and one projection distally, and lateral acute projections (one in each side) near the coxa of gnathopod 2. Pereonite 3 with ventral lateral projections (one in each side of the pereonite), two medial and 1 distal projections. Pereonite 4 similar to pereonite 3 but lacking distal projection. Pereonite 5 with two projections proximally and another acute projections distally. Pereonite 6 with two dorsal projections. Pereonite 7 smooth.
Gills (Figs 2 and 3). Elongated, length about 1.5 times its width.
Mouthparts (Fig. 4). (Left mandible and upper lip lost during dissection; left mandible figured for the paratype 1 female, see figure 6) Right mandible with trituritive molar, moderately developed and dentate marginally. Threearticulate palp; medial article provided with two setae; distal article of palp the longest, with a setal formula 1-x- 1, being x=3 (although it could be considered as a formula 1-x- 0 with x=4); incisor five-dentate, lacinia mobilis looking like a blade, followed by two more blades; no sign of molar flake. Lower lip without setae; inner lobes with rounded margin. Maxilla 1 outer lobe carrying seven spines distally serrate, palp two-articulate, distal article with four apical setae and three medial setae. Maxilla 2 inner lobe slightly shorter than outer lobe, both with abundant setae apically. Maxilliped inner plate oval, carrying two short spines and several plumose setae; outer plate oval and elongate, with two apical plumose setae and several media non-plumose setae; palp four-articulate, scarcely setose, distal article (dactylus) slightly curved.
Antennae (Figs 2, 3 and 5). Peduncle of antenna 1 of the same length that head and pereonites 1 and 2 combined; second article the longest; flagellum with 16 articles. Antenna 2 as long as the peduncle of antenna 1; proximal peduncular article with a well-developed acute gland cone distally; swimming setae absent; flagellum two-articulate.
Gnathopods (Figs 2, 3 and 5). Gnathopod 1 basis of the same length than the combination of ischium, merus and carpus; grasping margin of propodus smooth; two proximal grasping spine, dactylus bifid distally. Gnathopod 2 inserted on the anterior end of pereonite 2; basis shorter than pereonite 2, with a distal acute projection; ischium rectangular with a distal acute projection; merus rounded; carpus short and rectangular; palm of gnathopod 2 propodus very setose, with proximal projection provided with one grasping spine, and two large projections distally.
Pereopods (Figs 2, 3 and 5). Pereopod 3 and 4 absent. Pereopods 5-7 increasing in robustness, attached to the distal end of pereonites, six-articulate, setose and provided with two grasping spines proximally.
Penes (Fig. 4) large, situated laterally, distinctive, oval, length ca. 2 times its width.
Abdomen (Fig. 4) with a pair of uniarticulate appendages situated laterally, two lateral lobe and a single dorsal lobe provided with two plumose setae.
Paratype female “1” (7.3 mm) (Figs 3, 6 and 7). Similar to the male except for the following characteristics: presence of oostegites on pereonites 3 and 4, both scarcely setose; pereonites 3 and 4 lacking acute dorsal projections; pereonite 4 lacking proximal lateral acute projections; gills smaller than in male and gills on pereonite 3 larger than gills on pereonite 4; gnathopod 2 propodus smaller and less setose than in male, distal projections scarcely developed; abdominal appendages smaller than in male and less setose.
description: Published as part of Zettler, Michael L., Freiwald, André & Guerra-García, José M., 2018, Cold-water corals off Angola as refuge for a new Aeginella species (Crustacea: Amphipoda: Caprellidae), pp. 535-546 in Zootaxa 4462 (4) on pages 538-540, DOI: 10.11646/zootaxa.4462.4.6, http://zenodo.org/record/1441837