Panathura baudini, Poore, Gary C. B., Lew, Helen M. & Ton, 2002

Poore, Gary C. B., Lew, Helen M. & Ton, 2002, Expanathuridae (Crustacea: Isopoda) from the Australian region, Zootaxa 82, pp. 1-60 : 39-43

Panathura baudini n. sp. ( Figs 24 & 25 )

Material examined.– Holotype. Australia. Victoria, S of Point Hicks (38°21.9'S, 149°20.0'E), 1000 m, WHOI epibenthic sled, G.C.B. Poore et al. on RV Franklin, 23 Jul 1986 (stn SLOPE 32), NMV J17203 (juvenile, 9.8 mm, with 1 slide). Paratypes. Type locality, NMV J17204 (1 male); J17207 (3 males, 5 juveniles); AM P41457 (3 males, 5 juveniles). Victoria. S. of Point Hicks (38°16.4'S, 149°27.6'E), 800 m, coarse shell and biogenic sediments, WHOI epibenthic sled, M.F. Gomon et al. on RV Franklin, 23 Jul 1986 (stn SLOPE 34), NMV J17205 (2 males, 5 juveniles). Tasmania. Off Freycinet Peninsula (42°2.2'S, 148°38.7'E), 800 m, coarse shelly sand, WHOI epibenthic sled, M.F. Gomon et al. on RV Franklin, 27 Jul 1986 (stn SLOPE 45), NMV J17206 (1 juvenile).

Description: Juvenile. Head longer than wide, with prominent broad rostrum between bases of antennae 1, with 3 pairs of lateral setules; eyes absent. Pereonites of equal width, 4 the longest and 7 half length of pereonite 6. Pleonites 1–4 of approximately equal length, 5 twice as long, 1–6 about as long as pereonite 6, pleotelson as long as pereonites 6–7; pleonite 4 with c. 10 marginal plumose setae laterally on epimeron, pleonite 5 with c. 20 marginal plumose setae laterally. Telson base 0.7 width of widest point, halfway along, dorsally concave, apex evenly rounded; telson with scattered dorsal setules and its apex with 7 setae on each side, starting from middle, first and second the longest, third to seventh short.

Antenna 1 peduncle with stout article 1, narrower articles 2 and 3; flagellum as long as last 2 peduncle articles, of short article 1 with pappose seta, article 2 elongate, articles 3–5 minute, with 0, 1, 2, 0, 2 aesthetascs. Antenna 2 peduncle longer than that of antenna 1, article 2 produced anteroventrally under article 3, articles 3 and 4 short, 5 longer than wide; flagellum of 1 long article and 7 smaller articles.

Mandible with weakly produced obscurely toothed incisor, lamina dentata of 4 or 5 partially fused blunt spines; molar process blunt; palp article 1 short with 1 seta, article 2 longer than 1, with 1 distal seta, article 3 quarter length of 2, with 4 distal setae. Maxilla 1 with 5 teeth on outer lobe. Maxillipedal endite reaching to middle of palp article 3, rounded, with 3 distal setae; palp articles 1–3 broad, article 2 with 1 mesial seta, article 3 longest and with 3 simple mesial setae and 1 lateral seta, article 4 tapering and with 2 mesial and 1 stout lateral setae, article 5 short and with 4 apical setae.

Pereopod 1 subchelate, with proximal articles stouter than in more posterior limbs; carpus triangular, with 3 setae on posterior margin; propodus twice as long as wide, palm axial, concave, with 5 setae, mesial face with 3 setae; dactylus weakly closing on palm, unguis about one­third its length. Pereopod 2 more slender than first; merus cupping triangular carpus; carpus not reaching anterior margin, with weakly setose posterior margin; propodus weakly swollen, palm with distal spiniform seta, few palmar fine setae. Pereopod 3 similar to pereopod 2. Pereopods 4–6 similar; carpus trapeziform; carpus and propodus each with 1 distal short spiniform seta and few finer setae; dactylus weakly curved, unguis one­third length. Pereopod 7 carpus more elongate than in more anterior pereopods; propodus with 1 distal spiniform seta and few other finer setae on posterior margin, plus 2 anterodistal double­pectinate setae.

Pleopod 1 operculiform, covering all other pleopods when pleotelson depressed; endopod half as wide and little longer than exopod, distally setose; exopod 2.3 times as long as wide, marginally setose. Pleopods 2–5 about three­quarter as long as pleopod 1; endopods longer, more rectangular and narrower than exopods, distally truncate and setose; exopods distally and laterally setose. Uropodal endopod longer than peduncle, reaching near to end of telson; endopod 1.8 times as long as wide, distally and laterally setose; exopods meeting in midline only anteriorly, 1.8 times as long as wide, with shallow marginal excavation, posteriorly obtusely angled, marginal setae well spaced.

Female. Unknown.

Adult male. Pleon more elongate than juvenile, pleotelson straightened. Antenna 1 flagellum of 16 articles. Pereopods more elongate; pereopod 1 palm setose. Pleopod 1 not operculiform; pleopod 2 appendix masculina longer than endopod; pleopods 4 and 5 without marginal setae.

Size: Juvenile to 9.8 mm; male to 6.7 mm.

Distribution: South­eastern Australian slope, 800–1000 m depth.

Etymology: For Nicolas Baudin (1754–1803), commandant of the French expedition aboard Le Géographe and Le Naturaliste which spent 1801–1804 collecting marine life in Australian waters.

Remarks: Panathura baudini n. sp. is most easily recognised by the absence of eyes and the strong anterior lobe on the anteroventral margin of the second article of antenna 2.

Figures

FIGURE 24. Panathura baudini n. sp. Holotype, NMV J 17203. Scale bar = 1 mm.

FIGURE 25. Panathura baudini n. sp. Holotype, NMV J 17203. Telson apex is reconstructed from specimens other than the holotype.