Paragathotanais wurundjeri, Błażewicz-Paszkowycz & Bamber, 2012

Błażewicz-Paszkowycz, M. & Bamber, R. N., 2012, The Shallow-water Tanaidacea (Arthropoda: Malacostraca: Peracarida) of the Bass Strait, Victoria, Australia (other than the Tanaidae), Memoirs of Museum Victoria 69, pp. 1-235 : 198-201

Paragathotanais wurundjeri sp. nov.

Figures 133–134

Material examined. 1 (J58566), holotype, Eastern Bass Strait , 60 km E of North Point, Flinders Island, Stn BSS 32 , 39º41.7'S 148º39.5'E, 115 m depth, muddy sand, 27 March 1979, coll. G.C.B. Poore ; 1 (J58567), paratype, Eastern Bass Strait , 24 km NNE of Eddystone Point, Stn BSS 163 , 40º43.9'S 148º32.5'E, 56 m depth, muddy sand, 14 November 1981 ; coll. R.S. Wilson ; 1 (J58568) , paratype, Eastern Bass Strait , 85 km NE of North Point, Flinders Island, Stn BSS 169 , 39º02.4'S 148º30.6'E, 120 m depth, muddy sand, 15 November 1981 ; coll. R.S. Wilson .

Description of female. Body ( Fig. 133A) slender, holotype 3.7 mm long, 8.5 times as long as wide. Cephalothorax pear-shaped, widest and laterally-rounded posteriorly, tapering towards anterior with slight rounded rostrum, 1.5 times as long as wide, as long as pereonites 1 and 2 together, naked; eyelobes and eyes absent. Pereonites hexagonal, pereonites 1 to 3 widest anteriorly, pereonites 4 to 6 centrally; pereonites 1 and 6 subequal in length, shortest, half as long as cephalothorax; pereonite 2 just longer than pereonite 1; pereonites 3 to 5 subequal in length, longer than wide and about 1.25 times as long as pereonite 1 (all pereonites respectively 1.4, 1.1, 0.9, 0.8, 0.9 and 1.0 times as wide as long). Pleon narrower than pereon, pleonites without pleopods, each five times as wide as long. Pleotelson pentangular ( Fig. 134H), one-half length of pleon and 1.4 times as wide as long.

Antennule ( Fig. 133B) of four articles, proximal article 2.9 times as long as wide, as long as distal three articles together, outer margin with four penicillate setae in distal half, and simple seta distally as long as second peduncle article; second article twice as long as wide, 0.4 times as long as first article, with two outer distal penicillate and single longer simple setae, one inner distal seta; third article 0.3 times as long as second article, with single inner and outer distal setae; fourth article as long as second, with five simple and one penicillate distal setae.

Antenna ( Fig. 133C) of six articles, proximal article compact, naked; second article nearly twice as long as wide, naked; third article just shorter than wide, half as long as second article, with fine dorsodistal seta; fourth article longest, twice as long as second article and four times as long as wide, with penicillate seta in proximal half and one simple and two penicillate distal setae; fifth article half as long as fourth with one distal seta; sixth article minute with five distal setae.

Labrum not recovered. Left mandible ( Fig. 133D) with rounded “teeth” on pars incisiva, slender hook-like lacinia mobilis, pars molaris flaccid, lanceolate, directed proximally. Labium ( Fig. 133H) with prominent setose mediodistal processes. Maxillule ( Fig. 133E) with ten distal spines and proximal tufts of setae, palp not recovered. Maxilla ( Fig. 133F) linguiform, naked. Maxilliped palp ( Fig. 133G) first article naked, second article with three inner distal setae; third article with three inner setae; fourth article distally with two shorter and two longer setae, longer setae finely denticulate in distal half; basis naked; endites distally with two setae and outer rounded tubercle. Epignath ( Fig. 133I) elongate, distally pointed, naked.

Cheliped ( Fig. 134A) basis compact, 0.7 times as long as wide, naked; merus subtriangular with single ventral seta; carpus 1.5 times as long as wide, with two unequal midventral setae, one fine dorsodistal seta and one fine mid-dorsal seta; propodus as long as wide, fixed finger 0.9 times as long as palm, with one ventral seta, three setae adjacent to cutting edge, tooth-like apophyses centrally and distally on cutting edge; dactylus stout, naked.

Pereopod 1 ( Fig. 134B) coxa with seta; basis slightly arcuate, slender, 5.2 times as long as wide, naked; ischium compact, with ventral seta; merus 0.4 times as long as basis, ventrodistally with seta and elongate slender spine 0.6 times as long as merus; carpus as long as merus, distally with dorsal finely-denticulate spine longer than carpus and one simple shorter and one finely-denticulate longer ventral spines; propodus 1.6 times as long as carpus, with two subdistal setae, shorter ventral spine; dactylus with proximal seta, slender unguis 1.8 times as long as dactylus, both together 0.8 times as long as propodus. Pereopod 2 ( Fig. 134C) similar to pereopod 1, but merus 0.85 times as long as carpus, propodus without subdistal setae. Pereopod 3 compact ( Fig. 134D), similar to pereopod 2, basis with ventral penicillate seta.

Pereopod 4 ( Fig. 134E) coxa naked; basis slightly stouter than those of anterior pereopods, 4.7 times as long as wide, with two midventral penicillate setae; ischium with two ventrodistal setae; merus one-quarter as long as basis, with two finely-denticulate ventrodistal spines; carpus 1.2 times as long as merus, distally with two ventral and one dorsal finely-denticulate spines and fine mesial seta; propodus as long as carpus, distally with two ventral finely-denticulate spines. and one longer and one shorter dorsal setae; dactylus sinuous, with fields of microtrichia, 1.6 times as long as curved unguis, both together 1.5 times as long as propodus. Pereopod 5 ( Fig. 134F) as pereopod 4, but carpus with lateral rather than dorsodistal spine; propodus with three short dorsodistal spines and no setae. Pereopod 6 ( Fig. 134G) as pereopod 5, but propodus with microtrichia and four dorsodistal spines.

Pleopods absent.

Uropods ( Fig. 134H) held ventrally beneath anterior of pleotelson; basis naked; exopodal process shorter than endopod, with one distal seta; endopod of one segment, with one subdistal penicillate seta, four simple and one or two penicillate distal setae.

Male. Unknown.

Etymology. The Wurundjeri were one of the indigenous hunter-gatherer tribes of the Melbourne region, from whom John Batman, in 1835, negotiated a “purchase” of 2,400 km 2 of land which became the site of the original settlement which developed into the city of Melbourne (noun in apposition).

Remarks. Larsen (2005) gave a key to the females of Paragathotanais , in which the present species fails at couplet 5 in having a relatively stout cheliped, but “shoulders” (supercoxal processes) on the pereonites. In addition to the species listed that publication, Guerrero-Kommritz (2003) described P. insolitus from the Angola basin, but that species is distinct in having only four articles in the antenna, and very reduced spination of the anterior pereopods; P. abyssorum Larsen, 2007 is distinguished from P. wurundjeri sp. nov. by the much more compact antennule, the more slender cheliped and the smaller spines on the anterior pereopods, inter alia (Larsen, 2007); P. vikingus Bird, 2010 has far more compact pereonites, a characteristically elongate and parallel-sided cephalothorax, and a distinct mandibular morphology ( Bird, 2010); P. zevinae (Kudinova-Pasternak, 1970) , moved to this genus from Paranarthrura by Larsen (2007), has a more compact antennule and a more slender cheliped (Kudinova-Pasternak, 1970). All of these species have a smaller exopodal process on the uropod. Finally, P. ipy Jóźwiak & Błaźewicz-Paszkowycz, 2011 , differs from P. wurundjeri in having no ventrodistal spine on the merus of pereopods 1 to 3.

Paragathotanais wurundjeri is the shallowest-recorded species of the genus discovered so far, having been collected on muddy sand at 56 to 120 m depth in the Eastern Bass Strait. All of the other species occur at depths greater than 200 m, and mostly at depths greater than 2000 m.