Paradoxapseudes paneacis, 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 : 16-21

Paradoxapseudes paneacis sp. nov.

Figures 10–12

Gollumudes larakia Błażewicz-Paszkowycz & Bamber, 2007b

(partim – shallow water specimens), non- Apseudes larakia Edgar, 1997 .

Material examined. 1 (J58580), holotype, 1 (J58581), allotype, 155 further specimens (J57662), paratypes, Crib Point Benthic Survey Stn CPBS 33 S/2, Western Port, 38º21.60'S 145º13.67'E, 13 m depth, 12 March 1965, muddy sand, Smith McIntyre Grab. 21 specimens (J57649), Stn CPBS 33 S, same data as holotype; 1 with oostegites (J55880), 3 specimens (J57659) , paratypes, Stn CPBS 23 N, 38º20.29'S 145º14.18'E, 10 m depth, 10 March 1965, sandy gravel; 7 specimens (J57672) , paratypes, Stn CPBS 23 S, 38º21.69'S 145º13.51'E, 11 m depth, 9 March 1965, muddy sand; 1 brooding (J56169), 20 specimens including and brooding, 1 brooding (J57674) , paratypes, Stn CPBS 41 N, 38º20.81'S 145º13.85'E, 13 m depth, 30 March 1965, gravel and sand; all Western Port, Crib Point Benthic Survey, Smith McIntyre Grab. 1 (J56292) , paratype, Western Port , “sublittoral”, 25 November 1971 .

Other material (as in Błażewicz-Paszkowycz & Bamber, 2007b). 1 individual (J53143), 50 m south of Twin Reefs , Venus Bay (38º41'S, 145º39'E), 9 m, 07 March 1982, coll. M. McDonald; 1 individual (J55759), 50 m east of Petrel Rock , Venus Bay (38º39'S, 145º42'E), 8 m, 05 March 1982, ( CPA 1 ) coll. M. McDonald and M.F. Gomon; 5 individuals (J55761), 1 km east of Harmers Haven, 500 m offshore (38º34'S, 145º40'E), 11 m, 06 March 1982, ( CPA 14 ), coll. C. Larsen and G. Barber ; 1 individual (J55762), 1 km east of Harmers Haven , 300 m offshore (38º34'S, 145º40'E), 6 m, 06 March 1982 ( CPA 15 ), coll. R . S. Wilson and C. Larsen; 1 individual (J55763), east side of Cape Paterson (38º41'S, 145º36'E), 6 m, 05 March 1982, ( CPA 12 ), coll. R . S. Wilson , G. Barber , et al.; 1 individual (J55765) Bennison Channel 1.0 km south of Granite Island (38º49'S, 146º23'E), 6.0 m, 23 November 1983, ( CIN 28 ), coll. G.J. Morgan.

Description of female. Body ( Fig. 10) dorsoventrally flattened, holotype 2.9 mm long, 5.8 times as long as wide, tapering towards posterior. Cephalothorax subrectangular, 1.4 times as long as wide, with large triangular rostrum; eyelobes and eyes present. Pereonites 1 and 2 subequal in length, 0.28 times as long as cephalothorax, with convex lateral margins, paired anterodorsal setae and posterolateral plumose setae; pereonite 3 longest, 1.5 times as long as pereonite 2, with anterolateral pointed apophysis, midlateral invagination and posterolateral rounded apophysis above pereopod attachment, and with lateral plumose setae and paired anterodorsal setae; pereonites 4 to 6 similar to, but progressively shorter than, pereonite 3, pereonite 6 being 1.26 times as long as pereonite 2 (all pereonites respectively 2.7, 2.5, 1.7, 1.8, 1.9 and 1.9 times as wide as long). Pleon three times as long as pereonite 6, narrower than pereon, with five free subequal pleonites bearing pleopods; each pleonite about three times as wide as long and extended laterally into sharp, triangular apophysis bearing plumose setae. Pleotelson subpentangular, with two rounded apophyses bearing plumose setae on each side, as long as last three pleonites together, just longer than wide.

Antennule ( Fig. 11A) proximal peduncle article 3.6 times as long as wide, outer margin with penicillate setae and sparse simple setae in distal half, inner margin with sparse simple setae and proximal serration; second peduncle article wider distally, 1.5 times as long as wide, 0.3 times as long as first, with three penicillate and five simple distal setae; third article 0.7 times length of second, about twice as long as wide; fourth peduncle article slender, half length of third. Main flagellum of 7 segments, aesthetascs present on second, third and fifth segments, seventh segment anaxial on sixth; accessory flagellum of three segments.

Antenna ( Fig. 11B), proximal peduncle article with subrectangular inner apophysis bearing two plumose setae. Second peduncle article twice as long as first, twice as long as wide, margins sinuous, with medial and distal simple setae on outer margin, medial and distal tooth-like apophyses on inner margin, the former with an adjacent plumose seta; elongate linguiform squama bearing two longer distal and two shorter subdistal setae. Third peduncle article as long as wide and one-quarter as long as second, with inner-distal spine-like apophysis; fourth and fifth articles 0.7 times as long as second. Flagellum of four segments.

Labrum (not figured) rounded, distally finely setulose. Left mandible ( Fig. 11C) with strong, crenulate pars incisiva, robust lacinia mobilis with three distal crenulations, setiferous lobe with two compound and three simple setae; outer margin finely denticulate; pars molaris ( Fig. 11C ") robust, with radial rows of distal rugosity; palp ( Fig. 11 C') of three articles, proximal article shortest with five simple setae, second article longest with single row of two longer and eight shorter finely setulose setae along distal half of ventral margin, third article with 11 finely setulose setae, distal setae much longer than more proximal setae; right mandible ( Fig. 11D) similar but without lacinia mobilis. Maxillule ( Fig. 11E) inner endite with slight outer apophysis, finely setose outer margin and four setulose distal setae, outer endite with eleven distal spines and two subdistal setae, outer margin finely setose, palp ( Fig. 11 E') of two articles, distally with four setae. Maxilla ( Fig. 11F) outer lobe of moveable endite with two subdistal setulose sickle-like setae and five distal setulose setae, inner lobe with eight simple curved setae and five stouter plumose setae; outer lobe of fixed endite with six compound distal spines and subdistal biserrate spine, inner lobe with three stout, proximally setulose setae and rostral row of 26 setae. Labium ( Fig. 11G) with setulose outer margin, palp with dense tufts of fine lateral setules and three simple distal seta. Maxilliped ( Fig. 11H) basis naked; first palp article with one very long plumose inner seta and adjacent fine simple seta, and small plumose outer seta; second palp article longer than wide, with inner rows of five ventral plumose setae and numerous distally-curved simple; third palp article nearly twice as long as wide, with inner group of nine simple curved setae; fourth palp article with one subdistal and seven distal simple setae. Endites ( Fig. 11 H') with three coupling hooks, outer margin densely setulose, distally with one simple seta and numerous slender, blunt, bifurcate spines, outer subdistal plumose seta. Epignath ( Fig. 11I) oval, with setulose distal spine.

Cheliped ( Fig. 12 A') basis 1.6 times as long as wide, with two ventroproximal setae on small tubercles, mid-ventral curved spine, two ventrodistal plumose setae; exopodite present, distal article with 4 plumose setae (as on male, Fig. 12A); merus with one longer and two shorter setae on ventrodistal shoulder; carpus widening distally, subpentangular, with stout, curved spine and three simple setae mid-ventrally; chela robust, palm of propodus just longer than wide, fixed finger two-thirds length of palm, ventral margin regularly setose, cutting edge of fixed finger with crenulations and central rugose tooth-like apophysis, numerous submarginal setae; dactylus stout, with crenulated cutting edge.

Pereopod 1 ( Fig. 12B) with conspicuous setose apophysis on coxa; basis 2.9 times as long as wide, dorsal margin bearing four plumose setae in proximal half, ventral margin with single proximal plumose seta, single mid-ventral and paired distal simple setae; exopodite three-articled, distal article with four plumose setae. Ischium with three simple ventrodistal setae. Merus widening distally, with ventrodistal row of simple marginal setae, and single long dorsodistal and shorter ventrodistal finely denticulate spines. Carpus just shorter than merus, with setose margins including paired dorsodistal setae longer than propodus, one dorsodistal and two ventrodistal finely denticulate spines. Propodus 0.6 times as long as carpus, with two dorsodistal and four ventral finely denticulate spines interspersed with single fine setae. Dactylus slender, claw short, together longer than propodus.

Pereopods 2 and 3 ( Fig. 12C, D) coxa with rounded, setose apophysis, basis four times as long as wide, sparsely setose, ventrodistal seta reaching past half length of merus; ischium half as long as wide, with fine dorsal seta, one short ventral seta and one ventral seta longer than merus; merus shorter than carpus, with two to four ventral setae, pair of ventrodistal spines, one very short, and single strong dorsodistal seta; carpus with ventrodistal spine with adjacent simple setae, smaller submarginal ventral spines, inner distal finely-denticulate spine and long dorsodistal simple setae exceeding tip of propodus; propodus longer than carpus, with three or four finely-denticulate ventral spines, one (P2) or two (P3) dorsodistal finely-denticulate spines, dorsodistal setae exceeding tip of claw; dactylus with ventrodistal seta, dactylus and claw curved, together as long as carpus.

Pereopod 4 ( Fig. 12E) basis three times as long as wide, ventrodistal seta reaching past half length of merus; ischium half as long as wide, with fine dorsal seta, two shorter ventral setae and one ventral seta longer than merus; merus 0.6 times as long as carpus, with one ventral seta and pair of ventrodistal finely-denticulate spines; carpus with paired mid-distal spines and ventrodistal row of five finely denticulate spines interspersed with simple setae; propodus 0.8 times as long as carpus, with two finely-denticulate ventral spines and group of numerous finely-setulose dorsodistal setae and single dorsodistal seta exceeding tip of claw; dactylus with ventrodistal seta, dactylus and claw curved, together just shorter than propodus.

Pereopod 5 ( Fig. 12F) similar to pereopod 4, but merus with single ventral spine, long dorsodistal and ventrodistal setae reaching or exceeding tip of carpus, carpus with two ventral spines and dorsodistal seta exceeding tip of propodus, propodus with one short and two longer setae, one of which longer than dactylus plus claw, and with ventral comb of 10 leaf-like spines in the distal half.

Pereopod 6 ( Fig. 12G) proportionately similar to pereopod 5, basis with seven plumose dorsal setae; ischium with single dorsal plumose seta; merus with two dorsal plumose setae; carpus with dorsal and ventral simple setae; propodus with small leaf-like spines ventrally and distally; dactylus plus claw slender, curved, together as long as propodus

Pleopods typical for genus ( Fig. 12H), basis with two inner but no outer plumose setae, endopod with eight plumose marginal setae, exopod shorter with seven plumose marginal setae.

Uropod ( Fig. 12I) biramous, basis with four distal simple setae; exopod broken, of at least four segments; endopod elongate, filiform, with about 14 segments.

Description of male. Generally similar to female, but with dimorphic cheliped ( Fig. 12A), basis stout, 1.5 times as long as wide, with ventroproximal setae on small tubercles, mid-ventral curved spine, ventrodistal plumose setae; exopodite present, distal article with 4 plumose setae; merus sparsely setose; carpus stouter than that of female, widening distally, almost triangular, with stout, curved ventral spine; chela robust, stouter than that of female, palm of propodus as long as wide, fixed finger almost half length of palm, ventral margin regularly setose, cutting edge of fixed finger with crenulations and subproximal rugose tooth-like apophysis, numerous submarginal setae; dactylus stout, with crenulated cutting edge. Setae on most articles longer than those of female.

Etymology. Named after Crib Point, the type locality, contrived from the Greek pahnee – a crib, and akis – a point.

Remarks. The shallow-water material described as Gollumudes larakia in Błażewicz-Paszkowycz & Bamber (2007) is in fact of this species, to which are added numerous further specimens, principally collected during the Crib Point Benthic Survey (see Poore, 1986). Paradoxapseudes paneacis sp. nov. is unusual in the genus in having long ventrodistal and dorsodistal setae on merus, carpus, ischium and basis of each pereopod. It is the only Australian species with a spine on the cheliped carpus, a feature also present in P. littoralis (from Japan), P. garthi (Menzies, 1956) from the Gulf of California, P.heroae (Sieg,1986) fromtheSubantarctic,and P.intermedius (Hansen, 1895) from the Mediterranean. P. paneacis is also the only Australian species to have inner proximal serration on the antennule peduncle (like only P. intermedius of the four species listed above); as well as the long distal setae on the pereopod article, the present species differs from P.i ntermedius in having more mandibular palp setae, fewer basis setae on pereopods 1 and 6, and in the conformation of the rostrum, inter alia.

All specimens were collected in Western Port on shallow sands at depths between 6 and 13 m.