Toulrabia willsi Barnard &amp; Williams 1995, n.sp.
Creators: name: Barnard, J. Laurens
name: Williams, W. D.
Publisher: name: Zenodo
Year: 1995
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Paramelitidae
Toulrabia
Toulrabia willsi

description: <i>Toulrabia willsi</i> n.sp. Figs 5- 7 Etymology. Named for the explorer William John Wills, 1834-1861. Type locality. Stream on Mount Toulrab, Stirling Ranges, Western Australia. Material examined. HOLOTYPE (Western Australian Museum, WAM 15-19), female "a" 6.14 mm, in type series collected 22 December 1965 by D.H.D. Edward. Other material examined (PARATYPES), female "b" 5.64 mm. Six other female specimens in same sample. Diagnosis. As in the genus. Description of holotype (female "a"). <i>Body</i> (Fig. 5): urosome poorly armed dorsally; length, up to 6.14 mm. <i>Head</i> (Fig. 5): rostrum obsolescent; eyes absent. <i>First antenna</i> (Fig. 5): length 0.66 ofbody, 2.1 second antenna, flagellum longer than peduncle, peduncular article 1 longest, article 3 shortest, setae sparse, flagellum with 23 articles, no calceoli, no aesthetascs; accessory flagellum 2-articulate, articles of primary flagellum uniform, sparsely setulate. <i>Second antenna</i> (Fig. 5): length 0.33 body; peduncle longer than flagellum, article 4 longer than 5, articles 3, 4 and 5 with moderate ventral setation, article 3 without dorsomedial spines; flagellum 7-articulate, moderately setose ventrally, lacking calceoli. <i>Upper lip</i> (Fig. 5): apical margin evenly rounded but connection to epistome and epistome itself slightly asymmetrical. <i>Left mandible</i> (Fig. 5): palp article 3 shorter than 2, article 2 with 6 medial marginal setae, article 3 with 4C, 14D, 3E; incisor 5-toothed, lacinia mobilis 4-toothed, 4 setose accessory blades; molar bearing distal plumose seta, several penicillate hooked brushy basal setae, other pubescence, and pair of immensely setulate chisel spines. <i>Right mandible</i> (Fig. 5): incisor 4-toothed; lacinia mobilis bifid, very broad, each flake denticulate; accessory blades of 2 plumose spines. <i>Rightfirst maxilla</i> (Fig. 6): palp article 2 with 7 thin apical spines, outer plate with 9 spines, most denticulate; inner plate with 2 apicomedial setae. <i>Left first maxilla</i> (Fig. 5): palp article 2 with 5 thick apical spines mostly fused to segment, one apicolateral thin spine and one subterminal apicolateral facial seta. <i>Second maxilla</i> (Fig. 6): outer plate outer apical margin with 1 small spinule, apicomedial margin of inner plate lacking setae. <i>Maxilliped</i> (Fig. 7): palp article 3 with ranks of thin setae on inner edge; inner plate (Fig. 5) with 1 ventrofacial spine. <i>First gnathopod</i> (Fig. 6): coxal plate with short setae apically, without posteroventral spine; article 4 without posterior hump, carpus weakly lobate; propodus subrectangular, longer than wide, posterior edge widely setose, posterolateral angle rounded, with 1 medial and 2 lateral spines, no lateral spine elongate, palm slightly oblique, convex; dactylus reaching end of palm. <i>Second gnathopod</i> (Figs 6, 7): similar; palmar corner with 2 lateral and 1 medial spines, coxal plate similarly setose. <i>Pereopods</i> (Figs 6, 7): coxa 3 with similar setae, coxa 4 emarginate, with similar setae; pereopods 3-4 slightly longer than gnathopod 2, pereopod 3 scarcely longer than 4, article 4 sparsely setose posteriorly, article 5 poorly spinose posteriorly, posterior spine formula = EEEE-EEE, posterior margin of article 6 on pereopods 3- 4 with spine formula of ES-ES-ES-ES-SS and EES-ESES-SS; pereopods 5-7 similar, each with 4 locking spines; coxae 5-7 bearing few setae on ventral margin of posterior lobes, article 2 weakly expanded and lobate posteroventrally, lobe obsolescent on pereopod 7, bearing thin medium to short posterior setae; dactyls of pereopods 3- 7 with accessory spine formula of 1-1-3-5-4. Gills of coxae 2-6 sausage shaped, of pereopod 6 not reduced. Oostegites (Fig. 7) lacking setae except for tiny apicomarginal pits. <i>SternaI (gills) processes:</i> segments 6-7 with sausageshaped sternal gills in formula of (on one side) 2-1, gills attached to front of lateral edge of segment, pair of gills on sternite 6 arranged transversely, lateralmost gill shorter. <i>Epimera</i> (Fig. 7): each epimeron posteroventrally quadrate, posterior margins scarcely convex, smooth and setulose, each epimeron with 3 ventral spines and lateral oblique ridge. <i>Pleon:</i> each dorsolateral posterior margin of pleonites 1-6 with following setal-spine formula (s=side, t=top): 1 = Es, 2 = Es, 3 = Es, 4 = Es, 5 = 0, 6 = EtSs; uropod 3 (Fig. 5) not extending beyond uropods I and 2 in entire animal, uropod lengths relative to uropod 1: uropod 2 = 0.66, 3 = 0.50. <i>Pleopods</i> (for specimen "b"): retinacula 2 per pleopod, one accessory; peduncles each with 5+2, 6+2+2+2, and 4+2 setae, rami extending equally, outer with 8-7-6 articles, inner with 5-5-5 articles, setae on basal articles 7-1-1-3, 5-1- 1-2, 3-2-1-2, none bifid. <i>First uropod</i> (Fig. 7): peduncle length 1.3 rami; outer margin with 1 apicodistal spine besides row of 5 dorsal spines, with 3 medial spines; rami of subequal length, both rami with 1 row of marginal spines. <i>Second uropod</i> (Fig. 7): peduncle about 1.0 x length of inner ramus, with 3 apicodorsal spines, 2 dorsolateral spines, medial margin with 3 spines, basalmost small; outer ramus subequal to inner, both with 2 rows of marginal spines in formula of 3-2, apices of rami on uropods 1- 2 with 5 spines. <i>Third uropod</i> (Fig. 7): peduncle length 0.80 outer ramus, longer than urosomite 3, with subdistal seta besides apical cluster of 3 spines; outer ramus proximal article with several irregular spine ranks, article 2 absent; inner ramus length 0.40 of outer, with 1 apical spine. <i>Telson</i> (Fig. 7): broader than long, shorter than urosomite 3; cleft 60 percent of its length; apices each with 3 spines in facial notches, 1 apicolateral setule, each lobe with pair of penicillate setules dorsolaterally at M.60. Distribution. Western Australia, Stirling Ranges.
description: Published as part of <i>Barnard, J. Laurens &amp; Williams, W. D., 1995, The taxonomy of freshwater Amphipoda (Crustacea) from Australian fresh waters: Part 2, pp. 161-201 in Records of the Australian Museum 47 (2)</i> on pages 168-172, DOI: 10.3853/j.0067-1975.47.1995.236, http://zenodo.org/record/4654824