Tryphosella seasana Lowry &amp; Stoddart 2009, sp. nov.
Creators: name: Lowry, J. K.
name: Stoddart, H. E.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Tryphosidae
Tryphosella
Tryphosella seasana

description: <i>Tryphosella seasana</i> sp. nov. (Figs 21, 22) <b>Type material.</b> Holotype, female, ovigerous (3 eggs), 5.0 mm, AM P77905, east of Fitzroy Reef, Queensland, Australia (23°32'53"S 152°16'44"E), baited trap 3, 100 m, J.K. Lowry &amp; K. Dempsey, MV <i>Reefknot</i>, 2-3 June 1994 (QLD 1078). Paratypes: male, 4.6 mm, AM P77906; male, 4.0 mm, AM P77907; female, 4.5 mm, AM P77908; 8 unsexed, AM P77909; 110 unsexed, AM P52156; same data as holotype. Paratypes: 32 unsexed, AM P52155, east of Fitzroy Reef, Queensland, Australia (23°32'53"S 152°16'44"E), baited trap 1, 100 m, J.K. Lowry &amp; K. Dempsey, MV <i>Reefknot</i>, 2-3 June 1994 (QLD 1076). Paratypes: 45 unsexed, AM P52157, east of Fitzroy Reef, Queensland, Australia (23°32'53"S 152°16'44"E), baited trap 3, 100 m, J.K. Lowry &amp; K. Dempsey, MV <i>Reefknot</i>, 3-4 June 1994 (QLD 1096). <b>Additional material examined.</b> 3 unsexed, AM P52654 (QLD 951); 23 unsexed, AM P52151 (QLD 952); 45 unsexed, AM P52152 and AM P52656 (QLD 953); 162 unsexed, AM P52153 and AM P52654 (QLD 954); 454 unsexed, AM P52154 (QLD 955 / SEAS); 1 male and 1 female, AM P48022 (QLD 1198); 1 unsexed, AM P48029 (QLD 1199). <b>Type locality.</b> East of Fitzroy Reef, Queensland, Australia (23°32'53"S 152°16'44"E), 100 m depth. <b>Etymology.</b> Named for the SEAS (Scavengers of Eastern Australian Seas) project. <b>Description.</b> Based on holotype female, 5.0 mm, AM P77905 and paratype female, 4.5 mm, AM P77908. <b>Head and body.</b> <i>Body</i> without dorsal carina. <i>Head</i> lateral cephalic lobes rounded, with apically rounded margins. <i>Antenna 1</i> slightly shorter than antenna 2; flagellum with strong 2-field callynophore, robust setae absent from proximal articles; calceoli absent; accessory flagellum with 4 articles. <i>Antenna 2</i> less than 40% of body length; peduncular articles 3 to 5 not enlarged, without brush setae; calceoli absent. <i>Mouthparts</i> forming a subquadrate bundle. <i>Epistome</i> slightly produced beyond upper lip, broadly rounded. <i>Mandible</i> molar with asymmetrically reduced column, proximally setose, distally triturating; palp attached midway, article 3 with proximal A3-seta. <i>Maxilla 1</i> outer plate with setal-teeth in 6/5 arrangement; setal-tooth 7, left and right symmetrical, cuspidate along most of sinsusoidal inner margin; palp distal margin with apical robust setae. <i>Maxilliped</i> inner plates well developed, about half the length of outer plate; outer plate with 2 long, slender apical robust setae; palp 4–articulate, article 4 well developed. <b>Pereon</b>. <i>Gnathopod 1</i> subchelate; coxa reduced, significantly shorter than coxa 2, tapering distally; basis sparsely setose along anterior margin; ischium long (length 3.1 x breadth); carpus long (length 3.1 x breadth), subequal in length to propodus, without posterior lobe; propodus longer than broad, margins subparallel, palm acute; dactylus inner face serrated. <i>Gnathopod 2</i> subchelate; carpus 2.3 x length of propodus; palm transverse; dactylus minute. <i>Pereopod 4</i> coxa with well developed posteroventral lobe. <i>Pereopod 5</i> coxa equilobate; basis about as long as broad, posterior margin slightly serrated, with well developed wedge-shaped posteroventral lobe. <i>Pereopod 7</i> basis posterior margin slightly serrated. <b>Pleon.</b> <i>Epimeron 3</i> posterior margin smooth, posterodistal corner acute. <i>Urosomite 1</i> with anterodorsal notch and slightly rounded boss. <i>Uropod 1</i> rami subequal. <i>Uropod 2</i> rami subequal, inner ramus without marginal constriction. <i>Uropod 3</i> with 1 plumose seta on inner ramus; rami subequal; outer ramus 2-articulate, article 2 long (about 0.5 x article 1); inner ramus extending beyond article 1 of outer ramus. <i>Telson</i> distinctly longer than broad, deeply cleft, with dorsal robust setae, with 1 apical robust seta on each lobe. <b>Male</b> (sexually dimorphic characters). Based on paratype male, 4.6 mm, AM 77906. <i>Antenna 1</i> flagellum with stronger 2-field callynophore; calceoli present. <i>Antenna 2</i> about half body length; peduncular articles 4 and 5 with brush setae; calceoli present. <i>Urosomite 1</i> anterodorsal notch slightly deeper. <i>Uropod 3</i> with plumose setae on both rami. <b>Habitat.</b> Scavenger on soft bottoms, 58 to 200 m depth. <b>Remarks.</b> <i>Tryphosella seasana</i> and <i>T. flynnana</i> both live along the east coast of Australia in the same general habitat, but <i>T. flynnana</i> lives farther north and although they overlap in depth, <i>T. flynnana</i> is more common in shallower water. The main differences between these species are the shape of the gnathopod 1 coxa (short and tapering in <i>T. flynnana</i>, very short and almost subquadrate in <i>T. seasana</i>) and the shape of gnathopod 2 palm (slightly obtuse in <i>T. flynnana</i>, transverse in <i>T. seasana</i>). The very short, almost subquadrate coxa 1 separates <i>T. seasana</i> from all other GBR lysianassids. <b>Distribution</b>. <i>Australia</i>. Queensland: east of Fitzroy Reef; east of Mooloolaba (current study).
description: Published as part of <i>Lowry, J. K. &amp; Stoddart, H. E., 2009, Lysianassidae *, pp. 561-597 in Zootaxa 2260 (1)</i> on pages 593-595, DOI: 10.11646/zootaxa.2260.1.31, http://zenodo.org/record/5308147