Bathypisella spinicauda Ortiz & Winfield & Ardisson 2022, sp. nov.
Creators: name: Ortiz, Manuel
name: Winfield, Ignacio
name: Ardisson, Pedro-Luis
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Eriopisidae
Bathypisella
Bathypisella spinicauda

description: Bathypisella spinicauda sp. nov.
(Figures 2–7)
Material examined
Holotype. Adult female, 5.0 mm total length (CNCR36449); collected from the type locality; 884 m depth; 20 August 2005; coll., María Teresa Herrera-Dorantes.
Paratype. Male 4.5 mm total length (CNCR36450), same data as holotype.
Other material. Juvenile male, 2.5 mm total length (CNCR36451), same data as holotype.
Type locality. SW Gulf of Mexico, OC-2005-Xcambó-2, cruise station 57_17 (19.000°N, 94.500°W). The material was collected from a soft bottom characterised by silty-clay sediments of terrigenous origin, at 884 m depth.
Diagnosis
The same as for the genus.
Description
Holotype. Adult female (CNCR36449), total length 5.0 mm.
Body (Figure 2). head as long as segments 1–2 of peraeonal combined, rostrum reduced; lateral cephalic lobe rounded; eyes absent. Antenna 1 (Figure 2) peduncle article 1 as long as head, 2 short setae on anterodistal corner, a curved seta subdistally in ventral margin, article 2 the longest, 1.2x longer than article 1, article 3, 0.6x as long as 2, flagellum 14– articulate; accessory flagellum 3–articulate, slightly longer than first two articles of flagellum, article 3 vestigial; antenna 2 (Figure 2) article 5, 1.3x longer than 4; flagellum 7– articulate, of which 3 articles are long and 4 short; cone antennal gland well developed, half the length of the basal article. Peraeonal segments 1–7 dorsally smooth; pleonal segments 1–3 dorsally toothed, biggest dorsal tooth on urosomal segment 1, smallest on segment 2, segment 3 smooth. Epimera poorly developed, very low, epimerum 3 posteroventral margin subacute.
Mouthparts (Figure 3). upper lip (Figure 3a) ovoid, with small cut ventrally. Lower lip (Figure 4b) outer plate truncated dorsally, inner plate not well developed, mandible lobe poorly concave. Maxilla 1 (Figure 3c) inner plate subtriangular, acute with 1 tiny seta distally; outer plate with 7 bifid distal setae; palp 2–articulate, article 1 shorter than 2, article 2 with 7 short and 4 long distal setae. Maxilla 2 (Figure 3d) outer plate larger than inner, with 12 distal simple setae; inner plate with 25 long, and 4 short setae, no facial setae. Mandibles (Figure 3e, f), strong triturative molar inserted basally, palp 3–articulate, article 3 shorter than 2, 2 long distal setae, 5–6 accessory setae, left mandible lacinia mobilis with 4 teeth, 6 incisors (Figure 3f); right mandible lacinia mobilis with 3 teeth, 5 incisors (Figure 3e). Maxilliped (Figure 3g) inner plate half the length of outer, with 3 odontoid distal teeth, 8 setae; outer plate with 4 odontoid teeth, 5 setae; palp 4–articulate, dactylus nail present.
Gnathopod 1 (Figure 4a). coxa quadrangular, notched posteroventrally, 4 simple setae; basis 0.8x as long as ischium, merus, and carpus combined, 4 long anterior margin setae basally, 3 distally, 11 long posterior margin setae; ischium subequal in length to merus, 6 subdistal posterior setae; merus 9 short and 4 long posterior margin setae; carpus subtriangular, as long as propodus, 11 long setae on anterior margin and 18 arranged in a tuft on posterior margin; propodus ovoid, 5 long setae on anterior margin, 3 long and 2 short distal setae, palmar margin oblique, 4 long and several short setae on palmar margin; dactylus slightly longer than palmar margin. Gnathopod 2 (Figure 4b) coxa quadrangular, similar to coxa 1, notched posteroventrally; basis as long as ischium, merus, and carpus combined, 5 short setae on anterior margin, 11 on posterior margin; ischium as long as merus, 2 setae on posterior margin, 3 long and 3 short setae on merus posterior margin; anterior carpus margin with 7 setae, 6 on posterior margin; propodus anterior margin with 4 long and 4 short setae, small lobe of 5 long setae distally; dactylus half the length of palm, palmar margin oblique, with 1 long and several tiny setae, a strong robust seta on palmar angle; oostegite thin, as long as basis, curved upward; gill absent.
Pereopod 3 (Figure 5a). coxa rectangular, ventral margin convex, notched posteroventrally; basis as long as ischium and merus combined, 13 posterior margin equidistant setae; ischium posteroventral corner with 2 short setae; merus with 6 anterior margin setae, 6 on posterior margin; carpus with an anterodistal seta, 5 on posterior margin; propodus anterior margin with 3 setae, a tuft of 6 setae distally, 8 setae on posterior margin; dactylus 0.6x as long as propodus, a midway posterior seta; oostegite curved upward, as long as basis; gill saccular, 0.8x as long as basis. Pereopod 4 (Figure 5b) coxa quadrangular, without posteroventral lobe, posteroventral margin notched; basis as long as ischium and merus combined, anterior margin with long and short setae; ischium with a posterodistal seta; merus with 2 anterior marginal and 2 anterodistal setae, 6 short posterodistal setae and a long posterodistal seta; carpus 0.8x as long as propodus, an anterodistal seta, 2 long and 2 short setae posteriorly; propodus 4 long anterodistal setae, 4 posterior and 2 subdistal setae; dactylus 0.3x as long as propodus, short and curved; oostegite as long as basis, curved; gill 0.9x as long as basis. Pereopod 5 (Figure 5c) coxa sub-quadrangular, a small posteroventral notch; basis tapering distally, 6 robust setae on basis anterior margin, 4 intermediate setae and 1 robust seta distally, posterior margin serrate, with tiny seta; ischium with 2 anterior setae, a posterior seta; merus 0.6x as long as basis; resting articles missing; oostegite 0.6x as long as basis; gill half the length of basis. Pereopod 6 (Figure 6) coxa quadrangular, shorter than 5, slightly notched on posteroventral corner; basis tapering distally, as long as ischium and merus combined, margins serrate, anterior with robust setae, tiny setae posteriorly; ischium with an anterodistal seta; merus 1.3x longer than carpus, margins with 3 medial and 2 distal setae; carpus 0.8x as long as propodus, 4 setae on anterior margin, 2 anterodistal, 1 posteriorly, and 2 posterodistal; propodus with 7 setae on anterior margin, 4 distally; dactylus half the length of propodus, 1 simple inner seta. Pereopod 7 (Figure 5e) coxa small, slightly notched posteroventrally; basis tapering distally, as long as ischium and merus combined, margins serrate, anterior with robust setae, tiny setae posteriorly; merus with 3 robust setae on both margins, 1 robust seta on anterior corner and another on posterior corner; rest of articles missing.
Uropod 1 (Figure 6a). peduncle 1.2x longer than rami, anterior margin with 1 robust basal seta and 3 short setae, 1 robust seta on posterior margin, an interramal spiniform process distally; rami subequal in length; inner ramus with 3 distal setae, 4 marginal setae; 3 marginal and 2 distal on outer ramus. Uropod 2 (Figure 6b) peduncle half the length of outer ramus, 2 short robust interramal setae, another minute distal seta; 4 marginal setae on outer ramus, 3 long distal setae; 3 long distal setae on inner ramus, other 4 marginal. Uropod 3 (Figure 6c) peduncle almost half the length of basal article outer ramus, 3 distal anterior setae, another distal posteriorly; outer ramus article 1 anterior margin with 4 couplets of 2–4 robust setae, 2 couplets of 2 setae on posterior margin, 5 setae distally; article 2 devoid of setae, almost 0.3x as long as article 1; inner ramus subequal in length to peduncle wide, cone-shaped. Telson (Figure 6d) deeply cleft, each lobe tapering to an acute tip, 1 inner submarginal mid-way robust seta, dorsal surface smooth.
Paratype. Adult male (CNCR36450), total length 4.5 mm. Body similar to that of the female. However, some differences included: gnathopod 1 (Figure 7a) carpus and propodus anterior margins devoid of setae, a series of short and equidistant setae, interspersed with longer ones, cover posterior margin of carpus and propodus. Gnathopod 2 (Figure 7b) slightly larger than 1, palmar corner defined by 2 strong robust setae.
Etymology. Named after the spinicauda for bearing pleonal and first two urosomal segments dorsally toothed.
description: Published as part of Ortiz, Manuel, Winfield, Ignacio & Ardisson, Pedro-Luis, 2022, A new deep-sea genus and species of Eriopisidae (Crustacea: Amphipoda: Senticaudata) from the Gulf of Mexico, pp. 1109-1121 in Journal of Natural History 56 (21 - 24) on pages 1111-1120, DOI: 10.1080/00222933.2022.2101958, http://zenodo.org/record/7049378