Pedinura mokari, Bruce, 2003

Bruce, N. L., 2003, New genera and species of sphaeromatid isopod crustaceans from Australian marine coastal waters, Memoirs of Museum Victoria 60 (2), pp. 309-369 : 363-365

Pedinura mokari sp. nov.

Figures 40–42

Material examined. Holotype. Male (3.2 mm), Snapper Point, Beachport, SA, 37°29.3´S, 139°59.6´E, 14 May 1990, 6.0 m, brown algae etc., G.C.B. Poore and R. S. Wilson ( NMV J39714 ).

Paratypes. Vic. Male (3.1 mm), wharf at Port Campbell , 38°37.5´S, 142°59.5´E, 8 Apr 1988, 5 m, wood and encrusting algae from wharf pile, R. T . Springthorpe and P.B. Berents ( AM P50942 ). Male (3.2. mm),?female (2.6 mm), juv. (1.8, 2.0 mm), 50 m offshore, E side of South Point , Twin Reefs , 38°41´S, 145°39´E, 4 Mar 1982, 11 m, rocky, C. Larsen, G. Barber and R . S. Wilson ( NMV J26228 ).?female (3.0 mm), SW of Eagles Nest, Venus Bay , 38°40´S, 145°40´E, 5 Mar 1982, 8 m, rocky, R . S. Wilson and G. Barber ( NMV J26226 ). 6 females (ovigerous 3.0– 3.5 mm, non-ovigerous 3.1–3.2 mm) , E side of Cape Paterson , 38°41´S, 145°36´E, 5 Mar 1982, 6 m, rocky, R . S. Wilson, G. Barber et al. ( NMV J26334 ) .

Description of male. Body about 3.0 times as long as greatest width, lateral margins subparallel, pereonites of subequal width; dorsal surfaces smooth, unornamented. Head anterior margin without transverse ridge, rostral process present. Head 1.5 times as long as pereonite 1, pereonites 1>2=3=4=5>6>7. Pleotelson lateral margins straight, converging towards posterior, posterior margin flat with median excavation.

Antennule peduncle article 1 1.3 times as long as proximal width, about 2.0 times as long as article 2; article 2 flattened, 0.9 times as long as wide; article 3 about 0.9 times as long as article 2; flagellum 5-articled, extending to anterior of pereonite 1, about as length of articles 2 and 3 combined. Antenna similar to type species, flagellum with 9 articles.

Epistome smooth, narrow, laterally encompassing labrum, widest anteriorly with distinct and convex anterior margin, lateral margins shallowly concave. Mandible incisor with 4 cusps; lacinia mobilis present; spine row of 4–5 serrate curved spines; molar process appearing large, with serrate margins or ridged surfaces; palp article 1 longest, without setae; article 2 without setae, article 3 with 7 biserrate setae, distal 2 setae being largest. Maxillule mesial lobe with 4 long and 2 shorter CP; lateral lobe with 10 peripheral simple RS on gnathal surface. Maxilla lateral lobe and middle lobe each with 4 curved, flat, finely serrate RS respectively, mesial lobe with about (not clearly observed) 8 RS, variously serrate. Maxilliped endite extending about half way along palp article 3, distal margin with 1 conical RS, 2 rounded RS, 1 cactus RS and 2–3 slender CP RS; palp articles 2–5 with about 5, 9, 10 and 9 setae respectively.

Pereopod 1 basis about 2.3 times as long as greatest width, about 1.4 times long as propodus, widest proximally; ischium 0.6 times as long as basis, 2.58 times as long as greatest width, inferior margin with 2 acute simple setae, one set at distal angle; merus about 0.4 times as long as ischium, 0.8 times as long as greatest width, inferior margin with 2 acute RS; carpus (inferior margin) 0.7 as long as merus, 0.7 times as long as wide, inferodistal angle with 2 simple setae; propodus 12 times as long as ischium, 32 times as long as greatest width, inferior margin with single proximal seta, inferomesial margin with 2 biserrate RS, inferodistal margin with 2 simple RS adjacent to base of dactylus; dactylus 0.5 times as long as propodus, unguis strongly recurved, inferior margin with few small cuticular scales, secondary unguis recurved with 2 basal cusps. Pereopod 2 with all articles slender; basis about 6.7 times as long as greatest width, about 1.3 times as long as propodus; ischium 0.8 times as long as basis, 4.7 times as long as greatest width, inferodistal angel with single seta; merus about 0.7 times as long as ischium, 3.1 times as long as greatest width, superior distal margin convex, inferodistal angle with single slender seta; carpus 1.1 as long as merus, 4.7 times as long as wide, inferodistal angle with 2 slender setae; propodus about as long as ischium, 5.7 times as long as greatest width; dactylus 0.6 times as long as propodus, unguis slender, apically falcate, secondary unguis flat and strongly pectinate, extending alongside unguI. Pereopod 3 similar to 2, but a little more robust. Pereopods 4–7 similar to pereopod 1, but more slender, carpus quadrate rather than subtriangular, propodus inferior margin without biserrate RS; all pereopods without trifid and biserrate setae. Pereopod 7 basis with proximal flange; carpus distal margin with 3 biserrate acute RS.

Penial processes separate, about 1.3–1.6 times as long as basal width, tapering distally to rounded apex.

Pleopod 1 exopod and endopod with c. 14 and 12 PMS respectively; rami of similar size, endopod 0.9 as long as exopod, 1.6 times as long as basal width, lateral margin converging slightly to rounded distal margin; exopod 1.5 times as long as greatest width, margins convex, distal margin broadly rounded. Pleopod 2 exopod and endopod with c. 20 and 11 PMS respectively, pleopod 2 endopod about as long as exopod, 2.0 times as long as greatest width, lateral margin strongly recessed at insertion point of appendix masculina; appendix masculina attached about one-quarter of way along mesial margin, about 4.4 times as long as wide, 1.1 times as long as endopod, apex bluntly rounded. Pleopod 3 exopod and endopod with c. 22 and 12 PMS respectively; both rami elongate, endopod very slightly (1.04) longer than exopod, 2.3 times as long as greatest width, proximal lateral margin convex. Pleopod 4 both rami with obscure ridges, exopod lateral margin with fine setae, exopod suture complete. Pleopod 5 both rami with indistinct ridges; exopod with 3 distal scale patches, transverse suture absent. Uropod rami flattened, margins provided with mebrana cingula; exopod inserted into lateral margin at about one-quarter from proximal margin, 02 times as long as fused endopod, triangular, apex subacute; endopod anterolateral margin weakly convex, posterolateral part rounded, mesial margin straight; mesially with 3 cluster of 2 sensory setae.

Female. Sexes similar, the dimorphism of the type species apparently not present in this species

Size. Males 3.1–3.2 mm, ovigerous females 3.0– 3.5 mm, non-ovigerous females 3.1–3.2 mm.

Etymology. Mokari is an Aboriginal word meaning new; noun in apposition.

Distribution. Vic. and SA, where it is sympatric with the more widely distributed P. flindersia ; 5–11 m, rocky habitats.

Remarks. Pedinura mokari is separated from the only congener, P. flindersia by the posteriorly indented pleotelson, the epistome being widest anteriorly and visible in dorsal view and the weakly expanded antennular peduncle articles 1 and 2.

Figures

Figure 40. Pedinura mokari sp. nov. A–D, holotype, remainder male paratype NMV J39721. A, dorsal view; B, lateral view; C, frons, ventral view; D, pleon and pleotelson, ventral view; E, antennule; F, antenna; G, maxilliped; H, left mandible; I, maxilla; J, maxillule.

Figure 41. Pedinura mokari sp. nov. Male paratype NMV J39721. A–C, pereopods 1, 2 and 7.

Figure 42. Pedinura mokari sp. nov. Male paratype NMV J39721. A–E, pleopods 1–5; F, uropod; G, penes.