Paradexamine aequiserrata Myers, 2009, sp. nov.
Creators: name: Myers, Alan A.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Dexaminidae
Paradexamine
Paradexamine aequiserrata

description: <i>Paradexamine aequiserrata</i> sp. nov. (Figs 7, 8) <b>Type Material.</b> Holotype, male, 2.5 mm, AM P77993, Third Beach, small bay in lee of wind (14°40.2' S 145°26.55' E), hand netting in water column, night lights, 2 m, J.K. Lowry, A.A. Myers &amp; L. Hughes (QLD 1805). Paratypes, 8 males, 1 female, AM P77994, same data as holotype. <b>Additional material examined.</b> 1 female, P77995 (QLD 1732); 1 male, AM P71344 (QLD 1805); 29 males, AM P71407 (QLD 1805); 3 males, AM P71527 (QLD 1805). <b>Type Locality.</b> Third Beach, Lizard Island, Queensland, Australia (14°40.2'S 145°26.55'E). <b>Etymology.</b> From the Greek 'aequalis' = similar and 'serrata' = saw-toothed, referring to the even-sized spines on the distal end of each telson lobe. <b>Description.</b> Based on holotype, male, 2.5 mm, AM P77993. <b>Head.</b> <i>Head</i> lateral lobes acute or subacute. <i>Eye</i> huge, more than half length of head, with black central core. <i>Antenna 1</i> peduncle article 1 without process on posterior margin. <i>Antenna 2</i> equal to body length; peduncle article 4 broader proximally, finely setulose; flagellum with 30+ articles. <i>Mandible</i> palp absent; incisor process lacking robust setal row. <i>Maxilla 1</i> palp stout, about three times as long as broad. <i>Labium</i> mandibular lobes acute. <i>Maxilliped</i> palp 4-articulate. <b>Pereon.</b> <i>Gnathopod 1</i> carpus longer than propodus; propodus not greatly expanded distally. <i>Gnathopod 2</i> carpus elongate, slender, longer than propodus. <i>Pereopods 3–7</i> simple or scarcely prehensile. <i>Pereopod 3</i> coxa, posterodistal corner rounded; dactylus more than half length of propodus. <i>Pereopods 5–7</i> of uniform morphology. <i>Pereopod 5</i> basis subrectangular, with posterodistal lobe, anterior margin with short robust setae. <i>Pereopod 6</i> basis pyriform, broadest proximally, posteroproximal margin convex, weakly serrate, posterodistal margin concave, smooth. <i>Pereopod 7</i> coxal gill present; basis slender or moderately expanded, much longer than broad, posterodistal margin concave or straight, smooth or weakly serrated. <b>Pleon.</b> <i>Segments</i> with the following dorsal spine arrangement (from urosomite 1 forwards): 3.3.3.0.0. <i>Epimeron 2</i> posteroventral corner produced into a strong spine. <i>Epimeron 3</i> posterior and ventral margins smooth, with a single strong posteroventral spine. <i>Urosome</i> with urosomites 2–3 fused. <i>Urosomite 1</i> with dorsal spine and two dorsolateral spines. <i>Uropod 3</i> rami with many long fine setae. <i>Telson</i> lobes distally serrated, each lobe with multiple serrations of even size and shape, without distal spine, with subdistal robust seta, without subdistal slender seta. <b>Female</b> (sexually dimorphic characters). Based on paratype, female, 2.5 mm, AM P77994. <i>Eye</i> large, about half or less length of head. <i>Antenna 2</i> shorter than body length; peduncle article 4 slender, parallel sided, weakly setulose; flagellum with 10–12 articles. <i>Uropod 3</i> rami lacking long fine setae. <b>Habitat.</b> Sand bottom in shallow water. <b>Remarks.</b> This species is very similar to <i>P.rewa</i> Myers, 1985, from Fiji, from which it differs in the more slender and less serrated basis of pereopod 7, in the more elongated carpus of gnathopod 2 and in the acute eye lobes of the male (rounded in <i>P.rewa</i>). <b>Distribution.</b> <i>Australia</i>. Queensland: Third Beach, Lizard Island (current study).
description: Published as part of <i>Myers, Alan A., 2009, Dexaminidae *, pp. 393-424 in Zootaxa 2260 (1)</i> on pages 403-404, DOI: 10.11646/zootaxa.2260.1.20, http://zenodo.org/record/5319784
description: {"references": ["Myers, A. A. (1985) Shallow-water, coral reef and mangrove Amphipoda (Gammaridea) of Fiji. Records of the Australian Museum, Supplement 5, 1 - 143."]}