Australocaris pinjarup, Poore & Collins, 2009

Poore, Gary C. B. & Collins, David J., 2009, Australian Axiidae (Crustacea: Decapoda: Axiidea), Memoirs of Museum Victoria 66 (2), pp. 221-287 : 238-241

Australocaris pinjarup sp. nov.

Figures 11 , 12 , 39

Material examined. Holotype. WA, off Bunbury, 33°00.35'S, 114°34.12'E – 32°59.37'S, 114°34.55'E (stn SS10-2005 067), 423– 397 m, 29 Nov 2005, NMV J53443 (male, cl. 10.1 mm, tl. 27 mm, damaged).

Description of holotype. Carapace smooth except for slight rugosity at base rostrum, with few setae on gastric region and rostrum. Rostrum 0.75 times length of front-to-cervical groove, narrow, with 5–6 short oblique lateral spines anterior to supraocular spine, continuous with lateral gastric carinae. Supraocular spines prominent. Lateral gastric carina unarmed. Submedian gastric carina obsolete, curved mesially between supraocular spines. Median gastric carina sharp on rostrum, unarmed. Sternite 7 (pereopod 4) deeply divided in midline over posterior two-thirds and with sharp oblique lateral ridge. Sternite 8 (pereopod 5) with setose ridge on anterior face at base of leg. Abdominal somite 1 pleuron ventrally truncate; pleuron 2 asymmetrical, posteriorly rounded; pleura 3–5 rounded; pleura 6 rounded.

Eyestalk, 0.3 length of rostrum; cornea unpigmented. Antennular peduncle reaching to midpoint of antennal article 4; article 1 swollen proximally, with small lateral spinule.Antennal article 1 unarmed; article 2 distal spine slender, directed slightly upwards, reaching distally to middle of antennal article 4; scaphocerite reaching distally beyond distal margin of article 5, with 3 strong spines on lower margin, 1 spine on mesial margin; article 3 with sharp mesiodistal spine on lower margin; article 4 about as long as article 2 (excluding distal spine), with mesial distal spine (left side only); article 5 about half length of article 4. Maxilliped 3 coxa and basis lower margin each with distal spine; ischium unarmed; crista dentata of about 20 teeth; merus with 2 spines; carpus with 1 spine.

Pereopods 1 symmetrical, flattened, carinate; coxa lower margin with 2 spines; basis lower margin with 1 spine; ischium lower margin with 2 spines; merus upper margin barely convex, with 3 distal spines, lower margin with 7 spines, lateral face smooth, mesial face smooth; carpus upper margin with 6 spines, lower margin with 3 spines laterally, mesial face smooth;propodus upper margin with 1 row of 4 spines, lower margin convex, with 9 spines, lateral face tuberculate, mesial face smooth; fixed finger 1.2 times as long as upper palm, cutting edge convex, with c. 15 irregular triangular teeth; dactylus upper margin with 4 spines along proximal half, lateral face smooth, mesial face smmoth, cutting edge denticulate; both fingers bearing setae.

Pereopod 2 ischium lower margin unarmed; merus lower margin unarmed; carpus 0.7 length of chela; propodus upper margin 0.5 length of dactylus. Pereopod 3 or 4 merus lower margin with 1 spine; propodus 2.3 times as long as dactylus, with oblique rows of simple setae but without robust setae except for one distally. Pereopod 5 missing.

Pleopod 1 minute, cylindrical. Pleopod 2 without appendix masculina; appendix interna third length of endopod.

Telson 1.2 times as long as wide, widest proximally, then approximately parallel-sided, lateral margin unarmed, distal margin truncate-convex,with posteromedian spine,posterolateral angle rounded, unarmed; dorsal face without oblique ridges or spines. Uropodal endopod 1.5 times as long as wide, without lateral spines, longitudinal ridge with 4 spines (none marginal). Uropodal exopod 1.6 times as long as wide, with 6 obscure lateral spines, no longitudinal ribs, posterolateral angle with 1 fixed spine and 1 robust seta; transverse suture unarmed.

Etymology. Pinjarup is the name of the Australian Aboriginal people inhabiting the coast close to the type locality (noun in apposition).

Distribution. WA, off Bunbury, 33°S, 114°E, c. 400 m depth (known only from type locality).

Remarks. The type specimen is in poor condition but sufficient features can be ascertained to enable the species to be described as a new genus and species. The single article of the male pleopod 1 is enigmatic and may not reflect the adult state.

Figures

Figure 11. Australocaris pinjarup gen. and sp. nov. a, lateral view. b, dorsal view of carapace, peduncles of antennule and antenna and antennae. c, telson and right uropod. d, sternites 7 and 8, abdominal somite 1 and pleopods 1 (ventral). e, pereopod 4–5 coxa (left, lateral). f, epistome, left antennule and antenna (ventral). g, pereopod 1 (left, lateral). h, same (carpus–dactylus, without setae, upper). All figures from holotype.

Figure 12. Australocaris pinjarup gen. and sp. nov. a, maxilliped 3. b, c, pereopods 2 (right), 3 or 4 (left). e, pleopod 2. All figures from holotype.

Figure 39. Australocaris pinjarup gen. and sp. nov. Photomicrographs of (left to right) maxilla 1, maxilla 2 (posterior epipod seta truncated), maxilliped 1, maxilliped 2.