Pakistanapseudes lucifer, 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 : 40-45

Pakistanapseudes lucifer sp. nov.

Figures 27–29

Material examined. 1 ovigerous (J28617), holotype, Stn MSL-EG 117, Eastern Bass Strait, 37º52.65'S 148º42.15'E, 49 m depth, February 1991, coarse sand; 4 (J28627) , paratypes, Stn MSL-EG 78, Eastern Bass Strait, 37º43.89'S 148º30.13'E, 27 m depth, 4 June 1991, coarse sand; 1 brooding, 2 with oostegites (J28611) , paratypes, Stn MSL-EG 99, Eastern Bass Strait, 37º53.29'S 148º15.40'E, 43 m depth, February 1991, coarse sand; 1 (J28630) , paratype, Stn MSL-EG 108, Eastern Bass Strait, 37º53.14'S 148º28.94'E, 45 m depth, February 1991, medium sand; 1 (J28627) , paratype, Stn MSL-EG 72, Eastern Bass Strait, 37º53.39'S 148º15.40'E, 43 m depth, 4 June 1991, coarse sand; 3, 1 brooding (J28629) , paratypes, Stn MSL-EG 104, Eastern Bass Strait, 37º49.89'S 148º30.13'E, 27 m depth, February 1991, coarse sand; 2 (J57574) , paratypes, Stn BSS170 , Eastern Bass Strait, 39º51.8'S 148º26.5'E, 130 m depth, 15 November 1981, fine sand, coll. R. S. Wilson; 1 (J57574) , paratype, Stn BSS169 , Eastern Bass Strait, 39º02.4'S 148º30.6'E, 120 m depth, 15 November 1981, muddy sand, coll. R. S. Wilson; 1 (J57574) , paratype, Stn BSS188 , Western Bass Strait, 38º38.2'S 142º35.0'E, 59 m depth, 20 November 1981, coll. R. S. Wilson; 1 (J51790) , paratype, Stn VC 27 C1, Western Bass Strait, 38º23.92'S 145º18.43'E, 40 m depth, 11 May 1998, fine sand; 2 (J51317) , paratypes, Stn VC 18 C3, Western Bass Strait, 38º30.2'S 144º15.00E, 40 m depth, 13 May 1998; 2 brooding (J57655), 1 with oostegites (J57646), 1 brooding (J57653), 1 (J57654) , paratypes, Stn CPBS 41 N, Western Port, 38º20.81'S 145º13.85'E, 13 m depth, 30March 1965, gravel and sand; 1 (J55925), 12 March 1965, 1 (J55902), 20 March 1967, 2 and 4 (1 with oostegites, 2 brooding) (J55885) , paratypes, Stn CPBS 32 S, Western Port, 38º22.06'S 145º14.10'E, 13 m depth, reef with sponge .

Description of female. Body ( Fig. 27A), dorsoventrally flattened, elongate, holotype 3.2 mm long (tip of rostrum to posterior of pleotelson), six times as long as wide, tapering towards posterior. Cephalothorax subrectangular, just longer than wide, with pronounced pointed rostrum curving downward, laterally indented at anterior of branchial chambers; eyelobes distinct, dark ocelli present. Conspicuous forward-pointing spine-like hyposphenium mid-ventrally between chelipeds ( Fig. 27C). Each pereonite laterally convex, with anterolateral seta (posterolateral seta on pereonite 1); pereonites 1 and 2 subequal, shortest, about 0.35 times as long as cephalothorax; pereonite 3 one-and-a-half times length of pereonite 1; pereonite 4 longest, nearly twice as long as pereonite 1, pereonite 5 just shorter than pereonite 4, pereonite 6 just shorter than pereonite 3 and narrowest (all pereonites respectively 2.7, 2.7, 1.8, 1.3, 1.3 and 1.3 times as wide as long). Pleon three times as long as pereonite 5, with five free pleonites bearing pleopods; pleonites with single midlateral seta on each side; pleonite 1- 0.8 times as long as wide, posterior pleonites progressively shorter. Pleotelson rectangular, wider posteriorly, 0.3 times length of pleon, 1.4 times as long as wide, with paired lateral setae.

Antennule ( Fig. 28A) proximal peduncle article 2.7 times as long as wide, with inner and outer subdistal tufts of setae and midlateral outer group of three penicillate setae and single simple seta. Article 2 about 1.4 times as long as wide, 0.34 times length of first, with inner and outer distal setae exceeding distal edge of third article, single outer distal penicillate seta. Article 3 just under half-length of article 2, as long as wide. Peduncle article 4 half-length of article 3, wider than long. Main flagellum sparsely setose, of twelve segments, three aesthetascs present on segment 4, four on segment 6, one on each of segments 8 and 10; accessory flagellum of five segments.

Antenna ( Fig. 28B) with naked proximal peduncle article (not figured) expanded on inner margin. Article 2 longer than first, with two simple setae adjacent to elongate squama bearing seven inner marginal and distal setae. Peduncle article 3 shorter than wide with inner seta. Article 4 half as long as second with inner penicillate setae; article 5 twice as long as article 4. Flagellum of six segments, first and second segments with setae longer than three flagellar segments.

Labrum rounded, simple, naked; epistome not obvious. Right mandible ( Fig. 28D) with five cusps on pars incisiva; setiferous lobe with three trifurcate, two bifurcate and one simple setae, pars molaris ( Fig. 28E) stout, blunt with distal rugosity and denticulate margin; palp ( Fig. 28 E') of three articles, proximal article with one distal seta, second article twice as long as first and naked, third article just longer than second and with two longer stout distal setae and one shorter subdistal seta. Left mandible ( Fig. 28C) as right but with dentate lacinia mobilis; outer margin finely denticulate. Labium with outer serrations, distally finely setose, palp ( Fig. 28H) with inner and outer fine lateral setules and two longer and two shorter distal spines, and conspicuous rounded inner apophysis. Maxillule ( Fig. 28F) inner endite with outer apophysis and finely-setose distal margin, and five plumose distal setae; outer endite with ten distal spines and three distally denticulate subdistal setae, outer margin finely setose; palp of two articles, distally with three setae graduated in length. Maxilla ( Fig. 28G) typical of genus, outer margin finely setose; moveable endite outer lobe with two subdistal and five distal finely denticulate setae, inner lobe with six plumose/denticulate setae; fixed endite outer lobe with simple, trifurcate and bilaterally denticulate distal spines, inner lobe with five longer plumose setae and rostral row of 24 setae. Maxilliped ( Fig. 28I) with simple setae; first palp article with short outer seta and long inner distal seta; second palp article with inner margin bearing proximal serrations and numerous setae largely in two rows, longest inner seta not reaching distal margin of article, single outer distal setae; third palp article with nine recurved inner setae; fourth palp article with eleven setae around distal margin. Endite ( Fig. 28J) distal margin with outer simple setae and inner blunt compound spines, two coupling hooks. Epignath not recovered.

Cheliped ( Fig. 29A) slender. Basis four times as long as wide, ventrally without spine but with single ventrodistal seta. Exopodite damaged. Merus with single ventrodistal seta. Carpus slender, four times as long as wide, naked. Chela not slender, palm (propodus) 1.6 times as long as wide with single inner and outer distal setae at base of dactylus and small dorsodistal seta; ventral margin of fixed finger with two setae; cutting edge of fixed finger without apophyses but with three setae. Dactylus shorter than palm, naked, with no apophyses on cutting edge.

Pereopod 1 ( Fig. 29B) generally bearing simple (not tapering) longer setae. Basis stout, 1.4 times as long as wide, with small ventroproximal and mid-ventral spine and larger ventrodistal spine, dorsal margin with four simple, fine setae. Exopodite damaged. Ischium with two shorter and one longer ventrodistal setae. Merus more than half length of basis, wider distally, with single dorsodistal seta and curved dorsodistal spine, row of mid-ventral setae, stout ventrodistal spine without adjacent setae. Carpus compact, as long as merus, 1.2 times as long as wide, with two short ventral and one longer dorsodistal blunt spines, sparse ventral and dorsodistal setae as figured. Propodus shorter than carpus, with four ventral blunt spines increasing in length towards distal margin interspersed with single, simple setae, two dorsodistal slender blunt spines and few setae along dorsal margin. Dactylus stout, with two ventral denticulations and two dorsal setae. Unguis distinct, pointed.

Pereopods 2 ( Fig. 29C) and 3 similar to each other. Basis four times as long as wide, with two dorsoproximal penicillate setae and two shorter and one elongate ventrodistal setae, longest seta exceeding tip of merus. Ischium as long as wide with one ventrodistal seta; merus short, 0.2 times as long as basis, much shorter than carpus, with three ventral setae, dorsal margin naked. Carpus elongate, three times as long as merus, with inner and ventral rows of setae, single dorsodistal seta. Propodus 0.8 times as long as carpus, with row of elongate, simple ventral setae, paired mesial setae, dorsoproximal penicillate seta and three dorsodistal setae. Dactylus slender, as long as propodus, with subdistal unguis forming bifurcate tip.

Pereopod 4 ( Fig. 29D) slender, similar to pereopod 2, basis 4.7 times as long as wide, without ventrodistal setae. Carpus 3.2 times as long as merus. Propodus with dorsodistal group of one short spine, and one longer slender spine and two setae all as long as dactylus; dactylus elongate, 0.8 times as long as propodus, bifurcate as pereopod 2. Pereopod 5 ( Fig. 29E) similar to pereopod 4 but propodus with ventral row of fine spinules and three dorsodistal setae; dactylus with subdistal unguis forming bifurcate tip. Pereopod 6 ( Fig. 29F) similar to pereopod 5 but propodus ventral and distal margin with row of some 19 small leaf-like spinules, dorsodistal group of four spines and single seta. Dactylus with subdistal unguis forming bifurcate tip.

Pleopods ( Fig. 27F) all alike. Basis naked; rami linguiform. Endopod longer than exopod, respectively with 12 and 10 marginal plumose setae.

Uropod ( Fig. 29G) biramous, basis with single inner and outer distal setae; exopod of nine segments; endopod over four times as long as exopod, 0.6 times as long as body length, of about 35 segments.

Description of male. similar to female (figured male 3.7 mm long, Fig. 27B), cephalothorax proportionately slightly larger, rostrum more pronounced. Antennule and antenna ( Fig. 27D) with multisegmented flagella bearing dense aesthetascs; squama of antenna fused to second peduncle article, with small distal spinule, fourth peduncle article short, fifth article with two simple distal setae. Cheliped not recovered. Pleopods with more elongate basis, with articulation ( Fig. 27E).

Etymology. named after the Devil, owing to its having bifurcated claws (“cloven hooves”) on all pereopods other than pereopod 1.

Remarks. bifurcation of the pereopod claws (used in this context to mean the combination of dactylus and unguis, whether fused or not) in Pakistanapseudes is a variable feature, ranging from no bifurcation (e.g. P. leptochelatus , P. bassi ), to a bifurcation resulting from the subdistal attachment of the unguis on the dactylus on pereopods 2 and 3, as, for example, in P. goofi Bamber & Sheader, 2003 , and finally to a subdistal fusion of the unguis to the dactylus on pereopods 2 and 3 as, for example, in P. tenuicorporeus (Shiino, 1963) ; apart from the present species, the only other species of the Pakistanapseudinae to have bifurcating claws (with an unfused dactylus) on pereopods 5 and 6 as well as 2 and 3 is Swireapseudes birdi Guţu & Iliffe, 2008 , but in that species the claw of pereopod 4 is not bifurcate, whereas the claw of pereopod 4 in P. lucifer sp. nov. is bifurcate, identical to those of the other pereopods.

Other distinctions of P. lucifer include the complete absence of setae on the basis of the pleopod: many other species lack outer (ventral) setae, but all appear to have inner (dorsal) setae, although the setation of the basis in P. leptochelatus is unclear. In addition, the basis of pereopod 1 is surprisingly short compared with other species, and all other species show some modification of the dactylus and unguis of pereopod 4 (where known), normally a marked reduction in size compared with the other pereopods (although it is larger in P. perulpa Błażewicz-Paszkowycz & Bamber, 2007 and P. ridculli Bamber, 2005 ): in the present species, it shows no difference.

In the very sparse setation of the mandibular palp, only P. brasiliensis Guţu 1996 , from Brazil, approaches P. lucifer , but that species has a naked proximal article and eight distal/subdistal setae on the distal article. The sparsity of setation on the cheliped and pereopods is more extreme than any other pakistanapseudid, while the presence of a ventral row of fine spinules on the propodus of pereopod 5 is unique in this group, and the presence of three subdistal setae on the outer endite of the maxillule is unknown in the Apseudomorpha , as far as we are aware, all other species having two when they are present.

With regard to the identification key to Australian Pakistanapseudes species given by Błażewicz-Paszkowycz & Bamber (2007), the only other Australian species with a pointed rostrum is P. australianus Guţu, 2006 , from Queensland, but that species has two setae on the pleopod basis, far more segments in the antennular and antennal flagella, and is without bifurcated claws on pereopods 2, 4, 5 and 6 (pereopod 3 has not been described).

Pakistanapseudes lucifer occurred throughout the Bass Strait, at depths from 13 to 130 m on sandy substrata.

Pakistanapseudes perulpa Błażewicz-Paszkowycz & Bamber, 2007

P.perulpa Błażewicz-Paszkowycz & Bamber, 2007a , 3–8, figs 1–3.

Material examined. 1 with oostegites, 1 subadult (J30441), La Trobe Valley Ocean Outfall Survey Stn MSL LV 4 T5 , Eastern Bass Strait, 1 km off Delray Beach , Victoria, 38°14'S 147°22'E, 15–16 m depth, 24 October 1989 ; 2 (1 with oostegites) (J30444), La Trobe Valley Ocean Outfall Survey Stn MSL LV 6 T8 , Eastern Bass Strait, 1 km off Delray Beach , Victoria, 38°14'S 147°22'E, 15–16 m depth, 29 August 1990 ; 4 (2 with oostegites) (J30405), La Trobe Valley Ocean Outfall Survey Stn MSL LV 6 S1, Eastern Bass Strait, 1 km off The Honeysuckles , Victoria, 38°22'S 147°12'E, 15–16 m depth, 28 August 1990 ; 6 (5 with oostegites) (J30409), La Trobe Valley Ocean Outfall Survey Stn MSL LV 6 S4, Eastern Bass Strait, 1 km off The Honeysuckles , Victoria, 38°22'S 147°12'E, 15–16 m depth, 28 August 1990 , SCUBA Airlift, coll. EPA & Marine Science Laboratory .

Remarks: this species was described originally from Moreton Bay, Queensland, from clean sandy substrata at depths between 7 and 28 m. The present material is within this depth range, but extends the distribution much further south. It has a rounded rostrum, setae on both margins of the pleopod basis, an overlong dactylus to pereopod 4, and is without bifurcating claws.