Paratanais malignus Larsen 2001
Creators: name: Błażewicz-Paszkowycz, M.
name: Bamber, R. N.
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Tanaidacea
Paratanaidae
Paratanais
Paratanais malignus

description: Paratanais malignus Larsen, 2001   
Figures 58–59  
 Paratanais malignus Larsen, 2001, 368–372, figs 11–13, 17.   
 Material examined. 1 (J56667), Stn BUN2, off Honeysuckle Hill, Bunurong, Victoria, 38º40.32'S 145º37.47'E, 10 to 11 m depth, 1 April 1997, SCUBA, coll. T, D. O’Hara. 2 (J56668), 1 (J56669), Stn WV 11, Beware Reef, near Cape Conran, Victoria, 37º49.21'S 148º47.23'E, 5 to 6 m depth, 15 April 1998, SCUBA, coll. T, D.O’Hara. 3 (J56670), Stn WV 13, Sailor’s Grave, off East Cape Conran, Victoria, 37º48.13'S 148º44.41'E, 4 to 5 m depth, 15 April 1998, SCUBA, coll. T, D. O’Hara. 1 (J56671), Stn WV 5, Cheviot Beach, Point Nepean, Victoria, 38º18'S 144º40'E, 1.9 to 3.5 m depth, 31 March 1998, SCUBA, coll. T, D. O’Hara. 1 (J56694), Stn BSS 213 T, Eastern Bass Strait, 24 km SW of Lakes Entrance, Victoria, 38º03'S 147º50'E, 45 m depth, 01 October 1983, otter trawl, coll. M. Gomon & R. S. Wilson. 1 (J56734), Stn BSS 181 S, Central Bass Strait, 26 km SE of Aireys Inlet, Victoria, 38º39.48'S 144º18.12'E, 79 m depth, very fine sand, 19 November 1981, WHOI epibenthic sledge, coll. R. S. Wilson. 1 (J56738), Stn BSS 188, Western Bass Strait, 30 km SSW of Warrnambool, Victoria, 38º38.12'S 142º35.00'E, 59 m depth, 20 November 1981, coll. R. S. Wilson. 1 (J56766), Stn PPBES 1218, Port Phillip Bay, off Brighton, Victoria, 37º54.45'S 144º58.30'E, 4 m depth, coll. Department of Fisheries & Wildlife Marine Pollution Studies. 3 juveniles (J57546), Stn BSS 158, Central Bass Strait, 66 km S of Rodondo Island, Victoria, 39º48.36'S 146º18.48'E, 82 m depth, sand with silt and mud, 13 November 1981, coll. R. S. Wilson. Numerous other lots in the collections of Museum Victoria.   
 This species is particularly recognizable owing to its having a leaf-shaped spine at junction of the chela fingers; other characterizing features are the rugose lacinia mobilis of the left mandible, and the dorsal field of marginal setules on article 2 of the antenna peduncle. The additional material found here allows some additions to the type-description of Larsen (2001). The original type-material included only females and mancae; the present material also includes the male, which is described below. Supplementary description of female. Body-length up to 3.7 mm. Distal spine on article three of antennal peduncle often not showing articulation; labrum densely setose (Fig. 58A). Pars molaris of left mandible with elaborate distal spination (Fig. 58B). Maxilla (Fig. 58C) subtriangular, naked. Maxilliped (Fig. 58D) endites with anteromedial seta (originally described as absent in the more limited type-material), second palp article with long simple seta in addition to serrated spine and finely shorter setulose seta.   
Cheliped (Fig. 58E) carpus with long inner seta; fixed finger of propodus with two ventral setae. Pereopods 1 to 3 (Figs 58F, G) with seta on coxa.  
 Description of male. Body (Fig. 59A) shorter than that of female, 2.6 mm long, 4.8 times as long as wide. Cephalothorax subtriangular, as long as wide, longer than pereonites 1 to 3 together; large eyes present, with large pigmented ocelli. Pereonite 1 shortest, pereonites 2 and 3 progressively longer, pereonite 3 twice as long as pereonite 1, pereonites 4 to 6 equal in length, 2.7 times as long as pereonite 1. Pleon with five free subequal pleonites bearing pleopods.   
Antennule (Fig. 59B) of seven articles, proximal article 1.2 times as long as wide, with inner tuft of penicillate setae; second article 0.7 times as long as wide, about half length of first, with inner seta longer than article width; third article less than half length of second with longer inner and shorter outer distal setae. Flagellum of four segments; first segment very short, with proximal and distal rows of aesthetascs; second segment 2.5 times as long as wide, with distal row of aesthetascs; third segment as long as second, with simple distal seta; fourth segment shorter than third, distally with two penicillate and five simple setae, and single aesthetasc.  
Antenna similar to that of female.  
Mouthparts (Fig. 59C) largely reduced. Maxilliped basis with single distal seta, endites naked, palp with simple setae longer than those of female.  
Cheliped (Fig. 59D) compact, more robust than that of female; carpus just longer than wide, with longer ventral and shorter dorsal single setae; propodus with inner comb-row of 14 setae; fixed finger with numerous fine spinules (“teeth”) along cutting edge; dactylus strongly curved, with two setae on inner margin.  
Pereopods (Fig. 59E, F, G) more slender than those of female, pereopods 2 and 3 similar to pereopod 1; posterior pereopods with bases about 2.5 times as long as wide, propodi nearly five times as long as wide and as long as carpus and merus together.  
Pleopods (Fig. 59H) similar to those of female, but setae longer.  
Uropod (Fig. 59I) rami more slender than those of female; exopod almost as long as proximal endopod segment; proximal endopod segment with additional array of penicillate setae in proximal half.  
 Remarks. The type material of Paratanais malignus was collected in kelp epifauna at 4 to 4.5 m depth in Botany Bay, New South Wales. The present material extends the known distribution to throughout the Bass Strait in depths from 2 to 82 m on sandy to muddy substrata.
description: Published as part of Błażewicz-Paszkowycz, M. & Bamber, R. N., 2012, The Shallow-water Tanaidacea (Arthropoda: Malacostraca: Peracarida) of the Bass Strait, Victoria, Australia (other than the Tanaidae), pp. 1-235 in Memoirs of Museum Victoria 69 on page 88