Antatelson cuneatum n. sp.

Figure 5–6

Material examined

Holotype. Australia, Victoria, Eastern Bass Strait, 7.3 km SSW of Cape Conran (37 o 52.65’S, 148 o 42.15’E), 49 m, coarse sand, Smith­McIntyre grab, Coleman coll, N, Sarda, RV, 4 June 1991 (stn MSL­EG 89), NMV J22647 (1 male).

Allotype. Australia, Victoria, Eastern Bass Strait, 8.6 km WSW of Cape Conran (37 o 51.19’S, 148 o 38.53’E), 51 m, mud­shell, Smith­McIntyre grab, Marine Science Laboratories coll, Sarda, RV, 28 September 1990 (stn MSL­EG 56), NMV J22648 (1 female).

Paratypes. Australia, Victoria, Eastern Bass Strait, 1.3 km WSW of Cape Conran (37 o 49.37’S, 148 o 43.02’E), 33 m, sand­shell, (stn MSL­EG 52), NMV J22581 (1) ; 3.2 km S of Cape Conran (37 o 50.63’S, 148 o 43.47’E), 49 m, sand­shell, (stn MSL­EG 55), NMV J22587 (6) ; 5.4 km SW of Cape Conran (37 o 51.28’S, 148 o 43.73’E), 50 m, sand­shell, (stn MSL­EG 57), NMV J22652 (2) ; 8.6 km WSW of Cape Conran (37 o 51.19’S, 148 o 38.53’E), 51 m, mud­shell, (stn MSL­EG 56), NMV J52747 (4 juveniles) all collected by Smith­ McIntyre grab, Marine Science Laboratories, Sarda, RV, 28 September 1990 ; 7.3 km SSW of Cape Conran (37 o 52.65’S, 148 o 42.15’E), 49 m, coarse sand, Smith­McIntyre grab, Coleman, N, Sarda, RV, 4 June 1991 (stn MSL­EG 90) , NMV J22588 (1).

Other material

Australia New South Wales, AMS, P 48537, 34°07’S 151° 10’E 40m; P 48539, Bate Bay, NSW, 34° 07’S 151°10’E, T­4­339 70m depth. Coll., The ecology lab Jan 1991; P 48542, Bate Bay, NSW, 34° 07’S 151°10’E, T­4­341 70m depth. Coll.: The ecology lab Jan 1991; P 48547, P48547 NSW, 28°36.8’S, 153° 37.8’E NSW­653 16m , shelly sand amongst turf on rocks, P 49723, Julian Rocks NSW, 28°36,8’S, 153°37.8’E, 15m ..

Australia, Victoria, Western Port NMV J39606; NMV J39608; NMV J39610; NMV J39609, NMV J39607 . Eastern Bass Strait, 10.4 km ESE of eastern edge of Lake Tyers NMV J22642, NMV J22590; NMV J22651, NMV J22582, NMV J22641 . 18.1 km W of Pt Ricardo (37 o 49.30’S, 148 o 25.44’E) NMV J22635). 4.6 km S of Cape Conran (37 o 51.43’S, 148 o 43.73’E) NMV J22580; NMV J22578; NMV J22636; NMV J22646; NMV J22584; NMV J22634; NMV J22649; NMV J22586; NMV J22585; NMV J24510; NMV J22637; NMV J22643 (1); NMV J22589; NMV J22644; NMV J22639; NMV J22645;, NMV J22650; NMV J22579 (2); NMV J22577 .

Diagnosis

Antenna 1 article 1 nasiform process reaching half of article 3. Mandibular palp with 2 articles. Gnathopods 1, 2 both palms well defined, oblique, hind margins parallel to front margins; gnathopod 1, 2 propodi length equal or more than twice as wide. Pereonite 4 on each side a thickened small knob on the widest spot. Uropod 1, 2 surpassing length of telson.

Description

Length, 1.5–2.5mm.

Antenna 1 subequal antenna 2. Antenna 1 article 1 large, nasiform process surpassing end of article 2; article 3 <article 2; flagellum accessorium minute; flagellum in male with long aesthetascs. Antenna 2 article 4 <article 5, flagellum with 6–7 articles.

Mandibular incisor well developed, with broad cusps; raker spine row with 4 strong robust setae; no clearly developed molar cusp; palp with 2 articles, the second about double length of first, with long distal seta; or articulation of third article not seen. For other mouthparts and coxae see Thaumatelson herdmani .

Gnathopod 1 palm about as long as hind margin, oblique, defined by group of setae and robust setae; carpus triangular, with 2 long robust setae (one plumose), merus rectangular, distally one long and one very short seta, hind margin densely beset with short fine setae; basis distally widened by flange. Gnathopod 2 longer, but not broader than gnathopod 1; palm clearly shorter than propodus hind margin, defined by two robust setae; propodus distad widening. Carpus trapezoidal, distal one plumose and one smooth seta, along hind margin dense setae; merus rectangular; basis distally widened by anterior flange; anterodistally with group of stiff robust setae.

Pereopods 3–7 simple, feeble. P3 as in Gn2 basis anterodistally with group of stiff robust setae. In female only P3 with oostegites.

Uropods extending less far posteriorly in succession; on peduncle and rami 0–1 short robust setae. Uropod 3 ramus first article with strong distal robust seta, article 2 subequal article 1; upper side of all rami with fine serration.

Telson reaching end of uropod 3 ramus; insertion not hidden under urosome; distally rounded, setae lacking.

Etymology As shown in the habitus drawing seen from above, the shape of this species is like a little wedge; specific epithet is an adjective of cuneus = Latin for wedge.

Discussion

Among the five extant species of Antatelson this new one resembles only A. antennatum, as all others have dorsal body­processes. From A. antennatum it differs by the narrower gnathopods.

Distribution Australia, Victoria, Western Port and Bass strait; New South Wales.

Ecology In sand, shell or mud, in depth of 15– 51m.