Taxonomy of Paraplatyarthrus Javidkar and King (Isopoda: Oniscidea: Paraplatyarthridae) with description of five new species from Western Australia, and comments on Australian Trichorhina Budde-Lunde, 1908 (Platyarthridae) Author Javidkar, Mohammad Author King, Rachael A. Author Cooper, Steven J. B. Author Humphreys, William F. Author Austin, Andrew D. text Zootaxa 2017 4243 3 401 431 journal article 36268 10.11646/zootaxa.4243.3.1 1e56377e-aef3-4991-bcde-bc857fd36926 1175-5326 400092 06BB3BA9-E53C-4EF9-BD58-B853BF64B88D Paraplatyarthrus occidentoniscus Javidkar and King , sp. nov. Figs 14–16 , 2 E–F, 20A urn:lsid:zoobank.org:act:FDBD3D8A-A787-46F4-8056-7E136B072D8A Type material. Holotype : Male, WAM C 54794 (BES15551.10), Sturt Meadows pastoral station calcrete, Eastern Murchison region , Western Australia , Australia ; 28.70124°S , 120.90361°E , Jul 2010 , coll. W.F. Humphreys & S.J.B. Cooper. Paratypes : 5 females (WAM C 54795, BES15551.12; WAM C 54796, BES15551.23; WAM C 54797, BES15551.4; WAM C 54798, BES15551.22; WAM C 66914, BES15551.9), 5 males ( WAM C 54799, BES15551.14; WAM C 54800, BES15551.3; WAM C 54801, BES15551.1; WAM C 54802, BES15551.17; WAM C 66913, BES15551.8) (same locality and collection data as holoptype) . 2 females (WAM C 66915, BES17225.1; WAM C 66916, BES17225.2) (same calcrete as holotype), 28.70034°S, 120.90260°E, May 2012 , coll. W.F. Humphreys & S.J.B. Cooper. Diagnosis. Cephalic lateral lobes small. Eyes with 3 black ommatidia. Male pleopod 1 exopodite with no posterior point. Description. Male (WAM C 54794), Body pale. Cephalic lateral lobes small and rounded. Eyes with 3 black ommatidia. Antenna 1 medial article shortest, distal and basal articles approximately same size ( Fig. 14 A). Antennal 2 flagellum ( Fig. 14 B) with basal article shorter, about 1/3 length of distal one. Left mandible pars molaris with 5–6 plumose setae; 2 plumose setae on hairy lobe. Right mandible pars molaris ( Fig. 14 C) with about 6 plumose setae; hairy lobe bearing 2 plumose setae on top and down lobe, with few single fine setae between 2 plumose setae. Maxilla 1 outer endite ( Fig. 14 D) with outer group of 4 teeth covering about half of marginal area, also with inner group of 3 cleft teeth, 1 simple and 1 stalk-like tooth; inner endite ( Fig. 14 E) with plumose setae very close to each other so they can appear as single stout plumose seta, 1 single very fine seta on subapical outer marginal corner. Maxilla 2 ( Fig. 14 F) apically bilobate; inner lobe slightly smaller than outer one; inner and outer lobes delimited by fine suture. Maxillipedal endite ( Fig. 14 G) with 1 large seta close to subapical inner corner; distal articles of palp with 1 large proximal seta, 2 medial large setae and apical tuft of few long setae. Epimeron 1 rounded anteriorly. In dorsal view, posterolateral corner of pereonites 1–3 rounded. Posterolateral corner of pereonites 4–7 posteriorly directed ( Fig. 20 A). Pleonal epimeron 5 not reaching uropodal sympodite. Tergites 6 and 7 (one distant to lateral margin) with noduli laterales closest to posterior margin. Pereopod 1 ( Fig. 15 A) carpus inner margin with both small simple setae and long and short serrate setae but not dense, tuft of fine setae present; propodus with both small simple and large serrate setae; dactylus with long narrow seta not exceeding claws, outer claw sickle-shaped with small depression on medial part. Pereopod 7 ( Fig. 15 B) not showing any sexual dimorphism. FIGURE 14. Paraplatyarthrus occidentoniscus sp. nov. , (Holotype, ♂), A, antenna 1; B, antenna 2; C, right mandible (Paratype); D, maxilla 1 outer endite; E, maxilla 1 inner endite; F, maxilla 2; G, maxilliped. Scale bars: 0.1 mm. FIGURE 15. Paraplatyarthrus occidentoniscus sp. nov . , (Holotype, ♂), A, pereopod 1; B, pereopod 7. Scale bars: 0.1 mm. Pleon outline continuous with pereon. Pleopod 1 endopodite ( Fig. 16 A) slender, with simple apex including very fine setae, very fine setae in medial part; exopodite ( Fig. 16 B) heart-shaped, with no posterior point or setae on margins. Genital papilla ( Fig. 16 A) ventral sheath apically pointed and surpassed by long distally rounded lobe. Pleopod 2 endopodite ( Fig. 16 C) very slender; exopodite with 2 long marginal setae and very fine setae on other side ( Fig. 16 D). Pleopod 3–5 exopodites ( Fig. 16 E–G) with 3 simple and serrate marginal long setae. Pleotelson triangular and pointed. Uropodal exopodites surpassing pleotelson; endopodites, inserted at approximately same level (a bit upper) as exopodites; sympodite with extended circumflex-shaped incision on outer side. Etymology. The species name is composed of the Latin ‘occidente’ meaning west, referring to its Western Australian distribution, plus oniscus. Remarks . Paraplatyarthrus occidentoniscus sp. nov. is distinguished from the described Paraplatyarthrus species by a combination of characters, including eyes with 3 black ommatidia, the cephalic lateral lobes being small, and the male pleopod 1 exopodite with no or a very weak developed posterior point. The body length varies between 2.0 mm and 4.5 mm , and the body pigmentation varies from semi- to weakly-pigmented to pale ( Figs. 2 E, F). This species was referred to as Taxon 3 in Javidkar et al. (2015) . It is confined to a single calcrete aquifer, Sturt Meadows pastoral station, Eastern Murchison region, Western Australia .