Figorella formosa, Lowry & Stoddart, 2012

Lowry, J. K. & Stoddart, H. E., 2012, The Pachynidae fam. nov. (Crustacea: Amphipoda: Lysianassoidea) 3246, Zootaxa 3246 (1), pp. 1-69 : 25-26

Figorella formosa sp. nov.

( Figs 16–18 )

Type material. HOLOTYPE, female, 4.6 mm, MV J62417 , 44 km east of Nowra , New South Wales, Australia, Tasman Sea, 34°55.79'S 151°08.06'E, 429 m, muddy coarse shell, WHOI epibenthic sled, 22 October 1988, G.C.B. Poore et al., RV Franklin, stn SLOPE 56 . PARATYPES: 1 female, 3.5 mm, MV J62418 and 1 female, 4.5 mm, AM P.46669, same data as Holotype ; 1 female, MV J17532 , 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; 2 ovigerous females, 1 non-ovigerous female and 1 juvenile, MV J17533 , 14 km south-west of Marlo , Bass Strait, Victoria, Australia, 37°54'S 148°25.7'E, 26 m, sand and shell, Smith-McIntyre grab, 12 August 1989, G. Parry, stn MSL-EG 18 .

Etymology. The specific name formosa is taken from the Latin word for "beautiful."

Diagnostic description. Head lateral cephalic lobe large, narrowly rounded; ventral margin curved. Antenna 1 peduncular article 1 without posterodistal spine; accessory flagellum 2-articulate, article 1 short; flagellum without callynophore in female, [male not known]. Mandible lacinia mobilis a simple robust seta; lamina dentata absent; accessory setal row present, not on raised setose ridge; molar absent; palp attached slightly distally; palp article 2 broad, longer than article 3; article 3 with subparallel margins. Maxilla 1 outer plate with 9 setal-teeth in 5/4 arrangement, outer row setal-teeth with medial cusps; palp well developed, 2-articulate, with 2 apical slender setae. 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, posterodistal corner of palm attenuated, corner of palm with simple robust seta; dactylus reaching to corner of palm. Gnathopod 2 palm minute, transverse. Pereonite 4 without dorsal spines. Pereonite 5 without dorsal spines. Pereopod 5 merus without posteroproximal shoulder. Pereopod 6 basis with posteroventral lobe weakly produced; merus longer than broad, without posteroproximal shoulder. Pereopod 7 basis subovate with posterior margin smooth. Oostegites from gnathopod 2 to pereopod 5. Epimeron 3 posterior margin without projections, posteroventral corner broadly rounded. Uropod 3 biramous, inner ramus extending less than halfway along outer ramus. Telson much shorter than broad, entire.

Remarks. Figorella formosa is the only species in the genus which occurs in shallow water. The only other species of Figorella with a 5/4 setal-tooth arrangement is F. corindon . These taxa differ in the length of the second article of the mandibular palp (shorter than article 3 in F. corindon , longer in F. formosa ); in the length of the dactylus of gnathopod 2 (as long as the palm in F.formosa , over-reaching the palm in F. corindon ); in the palm development (minute in F. formosa , large in F. corindon ); pereopod 6 posteroventral lobe of basis (weakly produced in F. formosa , produced beyond the ischium in F. corindon ); pereopod 6 merus posteroproximal shoulder (absent in F. formosa , present in F. corindon ).

Distribution. South-eastern Australia; 26–429 m depth.

Figures

FIGURE 16. Figorella formosa sp. nov. Paratype, female, 3.5 mm, MV J62418, east of Nowra, New South Wales, Australia.

FIGURE 17. Figorella formosa sp. nov. Holotype, female, 4.6 mm, MV J62417, east of Nowra, New South Wales, Australia. Scales represent 0.1 mm.

FIGURE 18. Figorella formosa sp. nov. Holotype, female, 4.6 mm, MV J62417, east of Nowra, New South Wales, Australia. Scales represent 0.2 mm.