Drummondia marlo, Lowry & Stoddart, 2012

Lowry, J. K. & Stoddart, H. E., 2012, The Pachynidae fam. nov. (Crustacea: Amphipoda: Lysianassoidea) 3246, Zootaxa 3246 (1), pp. 1-69 : 13-14

Drummondia marlo sp. nov.

( Figs 7 , 8 )

Type material. HOLOTYPE, sex not known, 4.4 mm, MV J17534 , 33 km south-south-west of Marlo , Bass Strait, Victoria, Australia, 38°04'S 148°25.7'E, 28 m, sand and shell, Smith-McIntyre grab, 12 August 1989, G. Parry, stn MSL-EG 16.

Etymology. The specific name is a reference to the type locality; used as a noun in apposition.

Diagnostic description. Head lateral cephalic lobe large, broadly rounded; ventral margin curved. Antenna 1 peduncular article 1 with posterodistal spine; accessory flagellum 2-articulate, article 1 short; flagellum with strong 1-field callynophore in specimen of unknown sex. Mandible [lacinia mobilis not known]; [left accessory setal row not known], right modified into lamina dentata; molar absent; [palp attachment not known]; palp article 2 broad, longer than article 3; article 3 with subparallel margins. Maxilla 1 outer plate with 11 setal-teeth in 7/4 arrangement, some outer row setal-teeth with lateral and medial cusps; palp absent. Maxilliped inner plate small; outer plate large; palp 4-articulate, article 4 large. Gnathopod 1 chelate; ischium smaller than propodus, not swollen posteroproximally; carpus extremely compressed; propodus length about 1.8 × breadth, posterior margin well developed, palm with produced corner, corner of palm with complex robust seta; dactylus reaching to corner of palm. Gnathopod 2 palm minute, obtuse. Pereonite 4 without dorsal spines. Pereonite 5 with 1 dorsal spine. Pereopod 5 merus without posteroproximal shoulder. Pereopod 6 basis with posteroventral lobe weakly produced; merus longer than broad, with posteroproximal shoulder. Pereopod 7 basis subovate with posterior margin weakly dentate. Epimeron 3 posterior margin without projections, posteroventral corner broadly rounded. Uropod 3 biramous, inner ramus extending less than halfway along outer ramus. Telson as long as broad, entire.

Remarks. Unfortunately the left mandible of the only specimen of this species is lost. Drummondia marlo is most similar to D. corinellae , its geographical near-neighbour. The species differ in the shape of the head lobe, the relative length of gnathopod 1 propodus and the shape of coxa 5.

Distribution. Bass Strait, Australia; 28 m depth.

Figures

FIGURE 7. Drummondia marlo sp. nov. Holotype, 4.4 mm, MV J17534, off Marlo, Bass Strait, Victoria, Australia. Scales represent 0.1 mm.

FIGURE 8. Drummondia marlo sp. nov. Holotype, 4.4 mm, MV J17534, off Marlo, Bass Strait, Victoria, Australia. Scale represents 0.1 mm.