Nedsia scuiptilis Bradbury &amp; Williams 1996
Creators: name: Bradbury, J. H.
name: Williams, W. D.
Publisher: name: Zenodo
Year: 1996
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Eriopisidae
Nedsia
Nedsia scuiptilis

description: <i>Nedsia scuiptilis</i> <b>n.sp.</b> <b>Etymology.</b> Named for the sculpturing of the pleon. <b>Type locality.</b> Barrow Island, Western Australia. Western Australian Museum sampling site BES787. <b>Material examined.</b> HOLOTYPE (Western Australian Museum WAM 7-96) male 4.0 mm. <b>Diagnosis.</b> <i>Pleonites:</i> without dorsal spines. <i>Head:</i> rostrum obsolescent, lateral cephalic lobes moderately projecting. <i>First antenna:</i> bearing aesthetascs, <i>Second antenna:</i> short. <i>Upper lip:</i> symmetrical, not excavate. <i>Mandibular palp:</i> 2-articulate, articles equal in length, terminal article tapered terminating in 2 E-setae; accessory blades on rakers = 6 left, 4 R, with one interraker plumose seta on the right and one additional seta beyond the left rakers. <i>Maxillae:</i> without medial setae or pubescence except for the lateral margins of the second maxilla; inner plate of the first maxilla ovatoctriangular with six mid-medial to mediodistal plumose setae; palps symmetric; inner plate of the second maxilla with a row of medial setae barely extending onto the face apically with few other medial setae. <i>Coxae:</i> short, broader than long with few posterior spines. <i>Maxilliped:</i> inner plate bearing three distal plumose setae and three blunt naked terminal spines, without plumose medial setae, the outer plate bearing two distal plumose setae contiguous with a blunt naked tooth spine; palp articles 2-3 weakly setate laterally, setae at the dactylar base not organised into comb rows, the palp apex weakly produced, the dactyl with a moderately long nail. <i>First gnathopod:</i> palmar corner marked with one long lateral spine, moderate numbers of setae along palm. <i>Second gnathopod:</i> carpus barely lobate. <i>Pereopods:</i> 3-6 without accessory spinules on dactyls, posterior spine sets on article-6 of pereopod 3 evenly spaced, those on pereopod 4 uneven; dactyl of pereopod 7 with an extra terminal spinule. <i>Gills:</i> present on coxae 2-6. <i>Pleopods:</i> peduncles with 0,2,2 setae, 2 retinaculae and no accessory retinaculae. <i>Epimera:</i> epimeron 3 only with a small posteroventral tooth. <i>Uropods:</i> apicolateral corners of peduncles of uropods 1-2 with 3 and 2 spines respectively, the dorsal margins bearing few spines, the medial margin of uropod 1 with 2 apical spines. <i>Telson:</i> longer than broad, cleft 85%, bearing some medial spines. <b>Description of holotype</b> (male). <i>Body</i> 4 mm. <i>Pleon:</i> pleonite 6 without dorsal spines, bearing two laterodistal and single ventrodistal spines; pleonite 5 with distal dorsolateral spines. <i>Head</i> (Fig. 19): rostrum obsolescent; eyes absent. <i>First antenna</i> (Fig. 19): longer than second (broken at article-ll); flagellum longer than peduncle; peduncular articles 1-2 equal in length, 2.7x article-3, the first article bearing a cluster of ventral subdistal spines and setae, a row of small ventral spines, a dorsal row of three strong spines and a weak distal seta; flagellum moderately setate, bearing aesthetascs on some articles, article-l of the primary flagellum fused, accessory flagellum 2-articulate, second article tiny, extending to MO.8 of the first article of the primary flagellum. <i>Second antenna</i> (Fig. 19): moderately short, 0.3x body length; peduncle longer than flagellum, articles 4-5 subequal with weak setation, article-3 bearing a single dorsomedial spine and 4 ventrodistal spines; flagellum of 5 articles of diminishing dimension, lacking calceoli or aesthetascs. <i>Upper lip</i> (Fig. 19): apically convex, pilose and spinose; symmetrical. <i>Left mandible</i> (Fig. 19): without palp (broken), incisor 5 toothed, lacinia mobilis 5 toothed and elongate, extending to the apex of the incisor; mandible bearing 6 large setose and 1 small naked accessory blades between the incisor and molar, without interraker plumose setae or pubescence; molar triturative, without distal seta. <i>Right mandible</i> (Fig. 19): bearing a short pa1p of two subequa1 articles, the first truncate and naked, the second cone like bearing 2 short apical Esetae; incisor of 5 teeth; lacinia mobi1is shorter than incisor, bifid, bearing anteriorly a median row of short spines, posteriorly a marginal row of setae; mandible bearing 4 accessory blades, the first denticulate, the remainder setose, with a single interraker seta lying between first and second blades, and a row of setae extending posteriorly; molar triturative, without a distal seta. <i>Lower lip</i> (Fig. 19): bearing prominent inner lobes extending to MO.7 of the outer lobes; anterior surfaces of both lobes rugose, inner lobes naked, outer lobes bearing apicomedial spines and setae. <i>First maxilla</i> (Fig. 19): pa1ps of two articles, almost symmetrical, the left side more slender than the right, possibly regenerent, each with 5 apical and 1 subapical slender naked spines; inner plate ovatotriangular, without pubescence except for a small lateral terminal cluster, bearing on the medial margin to the apex 6 p1umose setae; outer plate bearing two naked and five denticulate terminal spines. <i>Second maxilla</i> (Fig. 19): outer dista1 margin of both plates pubescent, facial and medial regions lacking pubescence, outer plate bearing a single distal spine additional to the terminal setae; both plates without other setae. <i>Maxilliped</i> (Fig. 19): palp third article with medial setae confined to the margin of the apex, bearing a single facial spine adjacent the dactylar base; apical setae marginal, not organised to comb rows; dactyl with two accessory spines arising adjacent the base of the nail and as long as the nail; medial margin of the outer plate carved into 4 sinuous indentations, without marginal spines, but associated with each a pair of long submarginal, curved, blunt spines. <i>First gnathopod</i> (Fig. 20): coxal plate bearing 2 apical setae, the fourth article posteriorly bulbous and pubescent, carpus not lobate; propodus trapezoidal and slightly expanded apically, longer than wide, posterior margin naked but for a single submarginal spine and a pair of long apical spines; margin of the palm lined with fine setae anteriorly, posteriorly the palmar corner rounded, marked by a single long lateral bifid spine, the posterior margin of the hand pubescent; adjacent the palmar corner three stout bifid spines and two long terminally bifid spines; dactyl bearing a subterminal accessory spinule extending to the nail-less apex, which reaches to the palmar corner. <i>Second gnathopod</i> (Fig. 20): coxa bearing 2 anterior setae, the palm strongly oblique, bearing 7 lateral and 2 medial stout trigger spines and marginally bordered with short setae, the palmar corner defined by a long lateral trigger spine; dactyl bearing 3 small spines along the inner margin, and extending to a point slightly short of the palmar corner. <i>Pereopods</i> (Fig. 20): coxae 3-4 with 2 anterior setae only, pereopods 3-4 longer than gnathopod 2, pereopod 3 &lt;pereopod 4, both sparsely armed, pereopod 6-7 similar, pereopod 6 &lt;pereopod 7, articles 5 of pereopod 6 and 5-6 of pereopod 7 bearing a slight anterior keel, the anterior spines consequently slightly submarginal; coxae 6-7 bearing single posterior spines, articles 2 of pereopods 6-7 posteriorly expanded but not lobate and bearing stout trigger spines; dactyls of pereopods 3-6 without accessory spinules, pereopod 7 bearing a single subterminal spinule on the dactyl. <i>Gills:</i> flask shaped, present on coxae 2-6, gill 6 not reduced. <i>Sternal gills</i> absent. <i>Pleopods</i> (Fig. 21): each with 2 retinaculae, without accessory retinaculae, peduncles bearing 0,1,1 setae and 0,1,1 spines, all distal, the lateral spine of peduncle 3 bearing a trigger; rami extending subequally, of 7,6,6 inner and 8,8,7 outer articles; setae of basal articles of rami = 3-2,3-2,3-2. <i>Epimera</i> (Fig. 21): first epimera posteroventrally rounded, second posteroventrally quadrate, third slightly extended posteriorly and bearing a small posteroventral tooth, otherwise posterior margins smooth; epimera 1-3 bearing facial and submarginal ventral spines, the posterior corners marked by 2-1-1 spines, epimeron 2 bearing a single anteroventral marginal spine. <i>Pleon</i> (Fig. 21): pleonites 1-4 bearing dorsal and dorsolateral posterior setae, the posterior margins sculptured, with many serrations, less so on pleonite 4; without spines except for pleonite 5 which bears 3 dorsal and dorsolateral spines of moderate length, and pleonite 6 with 2 lateral and 1 ventrolateral posterior spines. <i>Uropods</i> (Fig. 21): first uropod 1.9x length of second, peduncle length greater than rami, outer margin bearing a strong basofacial spine and row of 4 dorsolateral spines, the last subapical, the medial margin bearing 2 anterior and 1 subapical dorsal spines; distal apices of peduncle bearing 1 medial and 1 lateral spines; inner ramus longer than outer, with single marginal spine at MO.6, and terminating in 5 spines, the outer ramus with 2 lateral spines at MO.4 and MO.6, terminating in an apical cluster of 4 spines; second uropod peduncle subequal to outer ramus, outer margin with 3 apical spines, inner margin with 1 mid-marginal and 3 apical spines; outer ramus bearing 1 mid-medial and 2 lateral spines at MO.5 and MO.7, and 4 terminal spines; inner ramus with 1 lateral spine at MO.7, a row of 4 medial spines and 4 terminal spines. Uropod 3 absent. <i>Telson</i> (Fig. 21): length equal to width, as long as urosomite 3; cleft 85% of its length, the subapex notched around an apical spine like extension, the notches bearing long plumose setae; left lobe bearing small lateral spines at MO.6 and MO.8, medial spines at MO.7 and MO.9, and a single penicillate facial setule at MO.5; right lobe bearing small lateral spines at MO.6 and MO.8, facial spines at MO.85, and single lateral penicillate spinule at MO.7. <b>Relationship.</b> <i>Nedsia sculptilis</i> in the form of the pleonites which are setate and complexly sculptured, and the epimera which are facially and submarginally spinous is similar to <i>N. macrosculptilis</i> and differs from other <i>Nedsia</i> in these ways. <i>N. sculptilis</i> is distinguishable from <i>N. macrosculptilis</i> in that the posterior margins of the fourth pleonite are without spines, and the medial margin of the outer plate of the maxilliped is without facial rugosity and is carved into 4 rather than 5 indentations. <b>Distribution.</b> Barrow Island, Western Australia.
description: Published as part of <i>Bradbury, J. H. &amp; Williams, W. D., 1996, Freshwater amphipods from Barrow Island, Western Australia, pp. 33-74 in Records of the Australian Museum 48 (1)</i> on pages 64-67, DOI: 10.3853/j.0067-1975.48.1996.280, http://zenodo.org/record/4654847