Araphura doutagalla, 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 : 139-144

Araphura doutagalla sp. nov.

Figures 93–95 Material examined. 1 (J58838), holotype, 1 (J58848), paratype, Central Bass Strait, 28 km E of Cape Farewell, King Island, Stn BSS 107, 39º32.8'S 144º16.00'E, 18 m depth, fine sand, 1 November 1980; coll. M.F. Gomon & G.C.B. Poore.

Description of female. Body ( Fig. 93A, B) slender, holotype 1.8 mm long, 7.4 times as long as wide. Cephalothorax pear-shaped, widest centrally, with distinct rounded rostrum, 1.4 times as long as wide, 2.6 times as long as pereonite 1, naked, eyes absent. Pereonites rectangular, although pereonites 1, 5 and 6 with convex lateral margins, bearing single anterolateral setae; pereonite 1 short; pereonites 2 to 4 subequal in length, 1.2 times as long as pereonite 1; pereonite 5 shorter, 1.1 times as long as pereonite 1; pereonite 6 shortest, 0.7 times as long as pereonite 1 (all pereonites respectively 1.6, 1.4, 1.3, 1.3, 1.4 and 2.3 times as wide as long). Pleon of five free subequal pleonites bearing pleopods plus pleotelson; each pleonite four times as wide as long, with single epimeral seta on each side. Pleotelson subpentangular, twice as long as each pleonite, 1.6 times as wide as long, with two laterodistal simple and one penicillate setae on each side of slight rounded mid-distal process ( Fig. 95I).

Antennule ( Fig. 94A) of four articles, proximal article 2.9 times as long as wide, as long as distal three articles together, with single outer distal simple seta preceded by four penicillate setae; second article longer than wide, half as long as first article, with two outer distal penicillate setae and adjacent simple seta 1.4 times as long as article; third article compact, half as long as second article, with two simple distal setae; fourth article tapering, with six simple and one penicillate distal setae.

Antenna ( Fig. 94B) of six articles, proximal article compact, fused to cephalothorax; second article as long as wide, with single dorsodistal and ventrodistal setae; third article as long as wide, 0.85 times as long as second article, with dorsodistal seta; fourth article longest, 4.4 times as long as wide, three times as long as third article, with penicillate seta and two simple setae distally; fifth article as long as third, with one distal simple seta; sixth article minute with four distal setae.

Labrum ( Fig. 94C) rounded, hood-shaped, naked. Left mandible not recovered; right mandible ( Fig. 94D) with four rounded “teeth” on pars incisiva, pars molaris stout with fine distal denticulations, ventral ones elongate. Labium ( Fig. 94F) simple, outer distal corner of both lobes setulate. Maxillule ( Fig. 94E) with eight finely-denticulate distal spines and distal setules, palp not recovered. Maxilla not recovered. Maxilliped ( Fig. 94H) palp first article naked, second article with one outer and two distal inner setae, third article with one longer mesial and three shorter distal inner setae, fourth article with five distal setae; basis naked; endites distally each with rounded tubercle and two fine setae, and with outer-distal microtrichia and longer inner seta. Epignath ( Fig. 94G) long, tapering, ribbon-shaped, naked.

Cheliped ( Fig. 95A) sclerite with triangular insertion into basis, rounded basis 1.6 times as long as wide, with simple dorsal seta, and with conspicuous proximal extension but not reaching to pereonite 1 ventrally; merus subtriangular with single ventral seta longer than width of merus, and covering about half of ventral margin of carpus; carpus 1.5 times as long as wide, with two midventral setae, one dorsodistal seta and one dorsoproximal seta, dorsal margin smooth; propodus 1.2 times as long as wide, with two ventral setae, outer face with curving ridge of rounded tubercles along fixed finger and three such tubercles dorsodistally, inner comb-row of three setae; fixed finger with three setae below cutting edge, cutting edge with three “teeth”; dactylus with dorsal rounded tubercles and two fine spinules on cutting edge.

Pereopod 1 ( Fig. 95B) not longer than others, coxa without apophysis, with seta; basis three times as long as wide; ischium compact, with one ventrodistal seta; merus as long as carpus, ventrodistally with seta as long as carpus and shorter distally-denticulate spine exceeding half length of carpus; carpus distally with mesial seta, distally-denticulate dorsodistal spine as long as carpus, and shorter simple ventrodistal spine; propodus 1.3 times as long as carpus, with simple ventrodistal spine; dactylus naked, unguis 1.8 times as long as dactylus, both together 1.2 times as long as propodus. Pereopod 2 ( Fig. 95C) similar to pereopod 1, basis 3.5 times as long as wide; carpus with additional distally-denticulate ventrodistal spine; dactylus and unguis together 0.9 times as long as propodus. Pereopod 3 ( Fig. 95D) similar to pereopod 2.

Pereopod 4 ( Fig. 95E) slightly more compact, basis 2.7 times as long as wide; ischium with two ventrodistal setae; merus as long as carpus, with two ventrodistal distally-denticulate spines; carpus with four distally-denticulate distal spines; propodus 1.4 times as long as carpus, with ventral fields of microtrichia, two ventrodistal distally-denticulate spines and one dorsodistal distally-denticulate spine; dactylus 1.3 times as long as unguis, dactylus and unguis not fused into a claw, the two together just shorter than propodus. Pereopod 5 ( Fig. 95F) as pereopod 4, but carpus with additional dorsodistal simple seta, ventrodistal microtrichia evident on merus and carpus. Pereopod 6 ( Fig. 95G) as pereopod 5, but propodus distally with two ventral and two dorsal distally-denticulate spines.

Pleopods ( Fig. 95H) all alike, with naked basis, endopod and exopod without setae on inner margin, outer-distal margins with respectively 7 and 8 plumose setae, exopod with additional separated proximal plumose seta.

Uropod ( Fig. 95I) longer than pleotelson, basis naked, exopod process 0.4 times as long as proximal endopod segment, with two distal setae; endopod of two segments, distal segment 0.6 times as long as proximal segment, setose as figured.

Male. Unknown.

Etymology. “Doutagalla ” was used by the European settlers at Melbourne as one of the early names for the colony: it may have been a mistranslation of the name of a prominent tribal elder, but is also said to translate as “treeless plain” (noun in apposition).

Remarks. Araphura doutagalla sp. nov., like the previous two species, is generally of the A. brevimanus form, but is also distinguished from that species and from A. whakarakaia as are those two taxa, and again has tuberculation on the chela. The patterns of this tuberculation are distinct from those of both A. pygmothymos and A. yarra ; in addition, A. doutagalla has a more robust body form (7.4 times as long as wide, compared with 9.7 or 8.8 times in the other two respectively), and conspicuously the uropodal exopod process is less than half the length of the proximal segment of the endopod (longer than or as long as half the length respectively). Its relatively stout mandibular molar process is similar to that of A. yarra (and not those of A, pygmothymos ), while the proportions of the merus and carpus of pereopod 1 are like those of A. pygmothymos (and not those of A, yarra ).

Araphura doutagalla was found in the Central Bass Strait north of Tasmania at a depth of 18 m on fine sand .