Ingolfiella rocaensis Senna & Serejo, 2005, sp. nov.
Creators: name: Senna, André R.
name: Serejo, Cristiana S.
Publisher: name: Zenodo
Year: 2005
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Ingolfiellidae
Ingolfiella
Ingolfiella rocaensis

description: Ingolfiella rocaensis sp. nov.
Material examined
Holotype, female, 1.3 mm, 03º51'747''S–33º49'497''W, Atol das Rocas, RN, Brazil, 14 m deep, from washed sponges, P.S. Young et al. col., Oct 2000, MNRJ 18115.
Diagnosis
Gnathopod 2 palm serrate, oblique, with a distal depression. Pereopods 3–4 with carpus longer than propodus, dactylus with a posterodistal spine and a slender, long and trifid claw. Oostegite 3–4 oval, distal margin truncated, with two long slender setae. Pereopod 5, dactylus with a large bifid claw. Uropod 1 biramous; endopod longer than exopod, with a row of four slender setae dorsally, a long subdistal slender seta at ventral margin and apex with a little slender seta.
Description
Body length (frontal margin of head to tip of telson) 1.3 mm. Body elongate, laterally compressed (Fig. 1 a). Head (Fig. 1 b), without rostrum, ocular lobe present between basis of first and second antennae; not extending beyond distal margin of basal article of the second antenna. Antenna 1 (Fig. 1 b), peduncular article 1 longer than articles 2 and 3 combined; flagellum 4­articulate, articles of flagellum with one aesthetasc and one or two slender setae; accessory flagellum 3­articulate; third article with one distal aesthetasc. Antenna 2 (Fig. 1 b), first article of peduncle fused with head; articles 4 and 5 subequal in length; articles 1–7 of flagellum with two slender setae; eighth article with four slender setae and one aesthetasc.
Gnathopod 1 (Fig. 1 c), coxa with one slender seta; basis slender and longer than ischium and merus combined; ischium with one slender seta on posterior margin; merus and carpus slender; carpus with posterior margin bearing two setae and palm oblique with two proximal stout setae and two distal slender setae; propodus with an anterior slender seta; dactylus with four elongate spines and one proximal strong spine, tipped with one slender seta, and appearing behind propodus. Gnathopod 2 (Fig. 1 d), coxa with one slender seta; basis longer than ischium and merus combined, bearing one slender seta on posterior margin; ischium and merus slender; carpus with posterior margin bearing two distal slender setae, a distal depression parallel to the palm, palm serrate, oblique, with two slender setae, one strong stout seta; claw stronger than that of gnathopod 1; propodus with one anterior slender seta; dactylus similar of that of gnathopod 1, slightly stouter. Pereopod 3 (Fig. 2 a), coxa bearing one anterior slender seta; basis slightly shorter than next three articles combined; ischium, merus and carpus, each with one posterior slender seta; propodus with one anterodistal slender seta and two posterodistal slender setae; dactylus carrying strong posterodistal spine and a trifid claw. Oostegite 3 oval, distal margin truncated, with two long slender setae. Pereopod 4 (Fig. 2 b) similar to pereopod 3, except coxa with two slender setae, merus with one anterodistal slender seta and one posterodistal slender seta, and propodus with only two posterodistal slender setae. Oostegite 4 similar to oostegite 3. Pereopod 5 (Fig. 2 c), coxa lacking seta; basis bearing two slender setae on posterior margin; merus with one posterodistal slender seta and one anterodistal stout seta; carpus with two posterodistal slender setae, one anterodistal slender seta and one anterodistal stout seta; propodus with two posterodistal slender setae and two anterodistal slender setae; dactylus carrying two distal slender setae and a stout, curved and bifid claw.
Pleopods 1–3 subtriangular. Uropod 1 (Fig. 2 d) biramous; peduncle with a long anterior slender seta; exopod thinner and shorter than endopod, bearing one medial slender seta; endopod with a row of four slender setae dorsally, ventral margin with a long sub­terminal seta, apex with a short distal seta. Uropod 2 (Fig. 2 e), peduncle with three slender setae on lateral surface; rami curved and tapered, endopod with two slender setae and exopod with three slender setae. Uropod 3 (Fig. 2 f) small, uniramous, 2­articulate; peduncle with one ventral slender seta; second article with an apical long seta. Telson fleshy (Fig. 2 f), with a long dorsal seta.
Remarks
Within the genus Ingolfiella, I. rocaensis sp. nov. is close to I. kapuri Coineau & Rao, 1972 and I. quadridentata Stock, 1979 in having gnathopod 2 palm serrate and claw of pereopods 5–7 bifid. The new species is distinguished from I. kapuri in the pereopod 3 carpus longer than propodus (not shorter); and from I. quadridentata in the presence of a depression on carpus of gnathopod 2 and claws of pereopods 3–4 trifid (not denticulate). Ingolfiella rocaensis sp. nov. can also be distinguished from the other species of the genus by the presence on the endopod of uropod 1 of an apical little slender seta. All the other species have apical spines or stout setae.
With the description of Ingolfiella rocaensis sp. nov. from the Atol das Rocas, the distribution of Ingolfiellidea is extended to the Brazilian waters. Previous records for the South Atlantic are South Africa and Argentine (Ruffo & Vigna Taglianti, 1989).
description: Published as part of Senna, André R. & Serejo, Cristiana S., 2005, Ingolfiella rocaensis sp. nov. (Crustacea: Amphipoda: Ingolfiellidea): first record of ingolfiellidean amphipods in Brazilian waters, pp. 1-6 in Zootaxa 962 on pages 2-5, DOI: 10.5281/zenodo.171248