Paraplatyarthrus occidentoniscus Javidkar and King, sp. nov.
Creators: name: Javidkar, Mohammad
name: King, Rachael A.
name: Cooper, Steven J. B.
name: Humphreys, William F.
name: Austin, Andrew D.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Isopoda
Paraplatyarthridae
Paraplatyarthrus
Paraplatyarthrus occidentoniscus

description: 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.
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.
description: Published as part of Javidkar, Mohammad, King, Rachael A., Cooper, Steven J. B., Humphreys, William F. & Austin, Andrew D., 2017, 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), pp. 401-431 in Zootaxa 4243 (3) on pages 418-420, DOI: 10.11646/zootaxa.4243.3.1, http://zenodo.org/record/400092