Apseudes poorei, Błażewicz-Paszkowycz & Bamber, 2007

Błażewicz-Paszkowycz, M. & Bamber, R. N., 2007, New apseudomorph tanaidaceans (Crustacea: Peracarida: Tanaidacea) from eastern Australia: Apseudidae, Whiteleggiidae, Metapseudidae and Pagurapseudidae, Memoirs of Museum Victoria 64, pp. 107-148 : 120-125

Apseudes poorei sp. nov.

Figures 7–9

Material. Female, holotype ( NMV J55747 ); Australia, Victoria, Western Port, off Crib Point (38°20.49'S, 145°13.51'E), 13 m, 30/03/1965, ( CPBS-N 41 ), A.J. Gilmour. Paratypes: 1 female with oostegites, 1 juvenile, ( NMV J53142 ), 2 specimens dissected on slides ( NMV J55943 ), same locality as holotype; 1 male ( NMV J55790 ), eastern Bass Strait , 8 km S of South East Point, Wilsons Promontory (39°12.54'S, 146°27.18'E), 65 m, 18/11/1981, ( BSS 180 ), R.S. Wilson; 1 individual ( NMV J55791 ), eastern Bass Strait , 37 km NNE of Eddystone Point (40°43.48'S, 148°37.12'E), 67 m, 14/11/1981, ( BSS 164 ), R.S. Wilson; 2 individuals (1 adult male), ( NMV J55792 ), Tasmania, eastern Bass Strait , 30 km N of North Point, Flinders I. (39°26.18'S, 147°48.42'E), 49 m, 17/11/1981, ( BSS 173 ), R.S. Wilson; 3 individuals ( NMV J55793 ), central Bass Strait , 35 km NE of Cape Wickham, (39°16.00'S, 144°05.24'E), 82 m, 23/11/1981, R.S. Wilson; 3 individuals ( NMV J55794 ), central Bass Strait , 47 km E of Cape Rochon, Three Hummock I. (40°23.48'S, 145°32.00'E), 66 m, 03/11/1980, ( BSS 113 ), M.F. Gomon and G.C.B. Poore; 2 mancas, ( NMV J55795 ), central Bass Strait , 47 km E of Cape Rochon, Three Hummock I. (40°23.48'S, 145°32.00'E), 66 m, 03/11/1980, ( BSS 113 ), M.F. Gomon and G.C.B. Poore; 6 individuals (2 mancas), ( NMV J55796 ), eastern Bass Strait , 28 km SSW of Marlo (37°59'S, 148°27'E), 51 m, 30/07/1983, ( BSS 207 ), M.F. Gomon and R.S. Wilson; 1 hermaphroditic, ( NMV J55797 ), central Bass Strait , 38 km SW of Cape Paterson (38°55.30'S, 145°17.00'E), 70 m, 12/11/1981, ( BSS 155 ), R.S. Wilson; 1 individual, ( NMV J55801 ), central Bass Strait , 38 km SW of Cape Paterson (38°55.30'S, 145°17.00'E), 70 m, 12/11/1981, ( BSS 155 ), R.S. Wilson; 1 ovi female (with well developed genital cone), ( NMV J55798 ), central Bass Strait , 44 km NE of Cape Wickham, King I. (39°22.00'S, 144°18.18'E), 60 m, 23/11/1981, ( BSS 203 ), R.S. Wilson; 1 male ( NMV J55799 ), Tasmania, eastern Bass Strait , 30 km N of North Point (39°26.18'S, 147°48.42'E), 49 m, 17/11/1981, ( BSS 173 ), R.S. Wilson; 6 individuals (4 females ovi), ( NMV J55800 ), central Bass Strait , 44 km NE of Cape Wickham, King I. (39°22.00'S, 144°18.18'E), 60 m, 23/11/1981, ( BSS 203 ), R.S. Wilson .

Description of female. Body dorsoventrally flattened, elongate, holotype 10.1 mm long (tip of rostrum to posterior of pleotelson), 6.5 times as long as wide, narrower posteriorly. Cephalothorax subrectangular, almost subcircular, as long as wide, anterior margin with triangular, blunt rostrum with notches just anterior to ocular lobes. Eyes present; eyelobes rounded; no lateral spiniform apophyses at anterior margin of branchial chambers. 6 free pereonites, all without lateral spiniform apophyses; pereonite 1 shortest, 0.4 times length of cephalothorax, pereonite 2 half as long as cephalothorax, both with lateral margins uniformly convex, pereonite 2 with slightly angular anterolateral corners; pereonites 3 to 6 subequal in length (5th longest), 1.7 times as long as pereonite 1, indented behind anterolateral rounded shoulders and mostly expanded posterolaterally at attachment of coxae; all pereonites respectively 2.7, 1.8, 1.5, 1.5, 1.2 and 1.3 times as wide as long; ventral hyposphenium on pereonite 6. Pleon 2.4 times as long as pereonite 6, of 5 free subequal pleonites bearing pleopods; pleonites dorsally convex, 2,5 times as wide as long, laterally expanded by spiniform apophyses. Pleotelson rectangular, 0.4 times length of whole pleon, 1.6 times as long as wide, with numerous lateral setae.

Antennule peduncle 4-articled, article 1 2.7 times as long as wide, with denticulations along proximal half of inner margin, setose as figured; article 2 0.3 times as long as article 1, with inner and outer distal tufts of long setae; article 3 0.4 times as long as article 2, article 4 one-third as long as 3rd, naked. Main flagellum of 15 segments, segments 13 and 15 bearing aesthetascs; accessory flagellum of 5 segments.

Antenna peduncle article 1 with inner denticulate apophysis; article 2 bearing inner denticulations and elongate squama with 13 marginal setae; peduncle article 3 as long as wide, with 1 seta; article 4 slightly longer than article 5, both with penicillate setae. Flagellum of 11 segments, most proximal segments with long outer setae.

Mouth parts. Labrum not seen. Left mandible outer margin finely setose, bearing strongly denticulated pars incisiva and lacinia mobilis, setiferous lobe with 4 trifurcate setae; pars molaris robust, distally spinose. Right mandible as left but without lacinia mobilis; mandibular palp of 3 articles, article 1 longer than wide with 6 long setae along inner margin, article 2 nearly 3 times as long as article 1 with 2 rows of longer and shorter simple setae in distal half; article 3 half length of article 2 with numerous inner simple setae increasing in length towards tip of article, longer distal seta as long as article. Maxillule inner endite with finely setose outer and inner margins, rounded outer apophysis and 5 finely setulate distal setae; outer endite with 11 distal spines and 2 subdistal setae, margins finely setose; palp of 2 stout articles, distally with 5 setae. Maxilla with smooth outer margin; outer lobe of outer endite with 2 setae on outer margin setulose at mid-length; other setae of outer endite simple; outer lobe of inner endite with simple setae, stout bifurcate and trifurcate spines and plumose inner and subdistal setae; inner lobe of fixed endite with rostral row of numerous setae guarding 5 longer setae. Labium not seen. Maxilliped basis with inner distal seta and stout spine; palp article 1 with seta on outer margin and inner distal seta and stout spine; palp article 2 longer than wide, with rows of numerous short setae and few proximal longer filtering setae on inner margin, outer margin with slender distal spine; palp article 3 longer than wide, with rows of filtering setae along inner margin; palp article 4 longer than wide, with 9 distal and 1 subdistal setae. Endite with flagelliform inner caudodistal seta and stout, spatulate, inner distal spines, slender compound outer spines and outer simple setae; 5 coupling hooks. Epignath large, cup-shaped, distal spine distally setulose.

Cheliped not slender. Basis 3.6 times as long as wide, dorsally with 3 plumose setae, ventrally with 3 proximal seta, midventral spine and tuft of 3 distal setae; exopodite present, 3-articled, article 2 naked, distal article with 5 plumose setae. Merus elongate, with 3 midventral and 4 subdistal setae. Carpus 4.2 times as long as wide, with 4 longer simple setae along ventral margin, sparse shorter setae along dorsal margin. Chela fingers shorter than palm, palm wider than long, ventral margin of fixed finger with dense row of setae; 4 setae near articulation of fixed finger and 2 at axis of gape; cutting edge of fixed finger with row of fine setules interspersing flat, rounded “teeth”, but no apophyses, distal claw pointed; dactylus with 3 subdistal setae but no apophyses on cutting edge, distal claw pointed.

Pereopod 1 with pronounced, setose, spiniform apophysis on coxa. Basis stout, twice as long as wide, with dorsoproximal seta, ventrodistal setae and small ventrodistal spine; exopodite present, 3-articled, article 2 naked, article 3 with 5 distal plumose setae. Ischium with 2 simple ventrodistal setae. Merus 0.8 times as long as basis, with midventral group of 4 setae, and 4 dorsodistal simple setae surrounding slender spine, shorter, stouter ventrodistal spine. Carpus less than half as long as merus, as long as wide, with 2 ventral and 1 dorsodistal stout spines. Propodus longer than merus, with 3 ventral and 2 dorsal stout marginal spines interspersed with simple setae. Dactylus stout, with mid-dorsal fine seta, unguis short, both together 0.7 times as long as propodus.

Pereopod 2 more slender. Coxa without spiniform apophysis. Basis 3.5 times as long as wide with tuft of ventrodistal setae, plumose midventral setae and mid-dorsal penicillate seta. Merus 0.9 times as long as carpus, with groups of midventral, ventrodistal and dorsodistal setae and slender ventrodistal spine, inner distal seta as long as carpus; carpus with similar setation and spination. Propodus just longer than carpus, dorsally and ventrally setose, with 2 ventral, 2 inner and 1 dorsodistal spines. Dactylus slender with 2 dorsal setae, unguis slender, the 2 together just shorter than propodus.

Pereopod 3 similar to pereopod 2, but basis with long inner setae, carpus with inner distal spines.

Pereopod 4 basis stouter, 3 times as long as wide, with 2 plumose setae and dorsal and ventral penicillate setae; merus two-thirds as long as carpus with paired ventrodistal spines and longer dorsodistal spine; carpus dorsally naked, with paired ventral spines and ventrodistal spines amongst slender setae; propodus with dorsoproximal penicillate seta, 2 ventral spines amongst row of fine marginal setae, dorsodistal tuft of numerous short and 5 long fine setae; dactylus plus unguis shorter than propodus.

Pereopod 5 similar to pereopod 4, but basis with ventroproximal spine, simple dorsal setae; merus with slender dorsodistal and shorter, paired ventrodistal spines; propodus with ventral row of fine denticulations in proximal half.

Pereopod 6 basis with dorsal and ventral plumose marginal setae, merus without spines, propodus with 24 ventral leaf-like propodal spines extending to distal margin of article.

Pleopods all alike. Basis elongate, with 2 dorsal and 2 ventral plumose setae. Endopod slightly longer than exopod; both rami slender, with plumose marginal setae, largely confined to distal half on exopod.

Uropod biramous, both rami filiform, multi-segmented. Basis with long setae distally on inner and outer margins; exopod less than one-quarter as long as endopod, with 13 segments; endopod elongate, 5.5 times as long as pleotelson, with more than 40 segments.

Male unknown.

Etymology. Named for Gary Poore of Museum Victoria, who collected much of the material analysed herein, in gratitude for his assistance in making all the tanaidacean material held at Melbourne available for study.

Remarks. In many ways, Apseudes poorei sp. nov. is close to the previous species, A. tuski , with a generally similar body, mouthpart and pereopod morphology (although differing in detail); conversely, it too has inner distal spines on the maxilliped basis and proximal palp article, as found in Annexos abditospina , also described above (although there are few other similarities between that and the present species). Along with A. bucospinosus , there seems to be a common theme of maxilliped spination amongst the eastern Australian species of Apseudinae . Other distinctions of A. poorei from A. tuski include the presence of a dorsodistal spine on the merus of pereopod 1, the extreme length of that merus, the proportionately longer pleotelson, 1 fewer ventral propodal spine on pereopod 1, longer flagella on the antennule and antenna, the inner apophysis on the proximal antennal peduncle article, a longer uropod endopod, and the presence of plumose setae on the bases of pereopods 2 and 4; all but the 1st of these also distinguish Apseudes poorei from the otherwise similar A. erythraeicus (see discussion under A. tuski ).