Leucothoe adelphe White &amp; Thomas, 2009, sp. nov.
Creators: name: White, Kristine N.
name: Thomas, James Darwin
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Ericales
Ericaceae
Leucothoe
Leucothoe adelphe

description: <i>Leucothoe adelphe</i> sp. nov. (Figs 3, 4) <b>Type material.</b> Holotype, male, 1.6 mm, AM P 71436, Three Sisters Bommie, Yonge Reef (14°36.104’S 145°37.126’E), coral rubble, back reef bommie, 17 m, C. Rakocinski, 3 March 2005 (QLD 1792). Paratype, female, 1.9 mm, AM P 71271, Horseshoe Reef, Lizard Island (14°41.21’S 145°26.49’E), clump of fibrous brown algae, large coral bommies surrounded by sand and rubble, 6 m, L. Hughes, 2 March 2005 (QLD 1767). <b>Additional material examined.</b> 3 males, AM P 79819 (JDT / LIZ 15). <b>Type locality.</b> Yonge Reef, Lizard Island, Queensland, Australia (14°36.104’S 145°37.126’E). <b>Etymology.</b> After the Greek ‘ <i>adelphe</i> ’, meaning ‘sister’ and referring to the type locality. <b>Description.</b> Based on holotype, male, 1.6 mm, AM P71436. <b>Head.</b> <i>Head</i> length less than pereonite 1+2, anterior margin weakly convex, without serrations or spines, anterodistal margin rounded with cusp, ventral cephalic keel transverse, rostrum small to medium; eyes with 10 or more ocelli, round. <i>Antenna 1</i> 0.3 x body length; flagellum 5-articulate, peduncle width less than 2 x article 2. <i>Antenna 2</i> 0.3 x body length, subequal to antenna 1; flagellum 5-articulate. <i>Mandibles</i> left mandible missing; right mandible lacking molar; incisor strongly dentate; lacinia mobilis small, with 7 accessory setae; palp 3-articulate, ratio of articles 1 <i>–</i> 3, 1.0:2.2:1.1, article 2 with 1 distal seta, article 3 with 2 distal setae. <i>Upper</i> and <i>lower lips</i> and <i>maxillae 1–2</i> missing. <i>Maxilliped</i> inner plates fused, distal margin notched, with short spines; outer plate smooth, reduced, reaching much less than half of palp article 1, with 3 proximal and 2 facial setae; palp 4 <i>-</i> articulate, article 4 wide, slightly recurved. <b>Pereon.</b> <i>Coxae 1–4</i> relative widths 1.0:0.9:1.1:1.4. <i>Gnathopod 1</i> coxa smooth, bare, anterodistal corner produced, narrowly rounded, distal margin straight, posterodistal angle subquadrate, facial setae absent; basis slightly inflated, anterior and posterior margins bare; ischium bare; carpus and propodus distally tapered; carpus length 9 x width, proximal margin with 2 dentitions, distal margin with 4 setae; propodus straight, palm dentate with 5 distal setae; dactylus smooth, reaching 0.1 x propodus length. <i>Gnathopod 2</i> coxa length subequal to width, slightly narrower than coxa 3, anterior margin smooth, anterodistally rounded, distal margin evenly rounded, posterior margin straight, facial setae absent; basis stout, widened distally, without tubercles or serrations, anterior and posterior margins bare; ischium bare; carpus 0.3 x propodus length, gently curved, distally truncate, anterior margin smooth; propodus posterior margin without spines/serrations, with 1 mediofacial setal row above midline, reaching approximately 0.5 x propodus length, 1 row of 8 submarginal setae, palm convex with 4 blunt projections; dactylus recurved, proximal margin smooth, anterior margin distally subacute, reaching 0.7 x propodus length. <i>Pereopod 3</i> coxa length subequal to width; smooth, bare, anterodistal corner over-riding distal face of coxa 2 and extending below it, anterior margin evenly rounded, distal margin oblique, posterior margin evenly rounded, facial setae absent. <i>Pereopod 4</i> coxa smooth, bare, anterior margin evenly rounded, distal margin evenly rounded, posterior margin mildly excavate, facial setae absent. <i>Pereopods 5–7</i> coxa facial setae absent; basis width length ratios 1:1.7, 1:1.9, 1:1.5, posterior margins smooth, bare. <b>Pleon.</b> <i>Epimera 1–3</i> bare. <i>Epimeron 3</i> posteroventral margin subquadrate. <i>Uropods 1–3</i> relative lengths 1.0:0.7:1.0; outer ramus 0.8 x inner ramus length. <i>Uropod 1</i> peduncle 0.7 x inner ramus length. <i>Uropod 2</i> peduncle 0.8 x inner ramus length. <i>Uropod 1–2</i> inner ramus proximal margin lined with short setae, with robust setae; outer ramus distal margin lined with short setae, with robust setae. <i>Uropod 3</i> peduncle and inner ramus subequal in length; inner and outer ramus proximal and distal margins lined with short setae; inner ramus with robust setae, outer ramus with 1 robust seta. <i>Telson</i> 1.7 x longer than wide, apex with weak point. <b>Female</b> (sexually dimorphic characters). Based on paratype, female, 1.9 mm, AM P 71271. <i>Gnathopod 1</i> carpus proximal margin without strong dentitions, weakly dentate anterodistally; propodus palm with fewer dentitions. <i>Gnathopod 2</i> basis anterior margin with 2 long and 2 short setae, anterodistal margin with row of 4 short setae; propodus mediofacial setal row with fewer setae; submarginal setal row with 5 setae; dactylus distally acute. <b>Habitat.</b> In coral rubble and fibrous brown algae from back reef bommies. <b>Remarks.</b> This species appears to be closely related to <i>Leucothoe micronesiae</i> J.L. Barnard, 1965 and <i>Leucothoe minuscula</i> Schellenberg, 1938 based on the small size, short mediofacial setal row and strong dentition of the gnathopod 2 propodus palm. J.L. Barnard (1965) noted that the only difference between <i>L. micronesiae</i> and <i>L. minuscula</i> was the size and development of the female gnathopod 2. Closer examination suggests that these species may need to be synonymised. <i>Leucothoe adelphe</i> <b>sp. nov.</b> differs from <i>L. micronesiae</i> and <i>L. minuscula</i> in its narrow, smooth basis of pereopods 5 <i>–</i> 7, its rounded propodus on gnathopod 2 and its shorter, less recurved propodus of gnathopod 1. The strong dentition of the gnathopod 2 propodus palm is shared with <i>Leucothoe ashleyae</i> Thomas &amp; Klebba, 2006, <i>Leucothoe hornelli</i> Walker, 1904, <i>Leucothoe stegoceras</i> Walker, 1904, <i>Leucothoe rudicula</i> <b>sp. nov.</b> and <i>Leucothoe serrata</i> <b>sp. nov.</b>, but differs in most other respects, namely the short gnathopod 1 dactylus. These species share the general shape of gnathopod 1 with species in the genus <i>Paraleucothoe</i>; however, the propodus of <i>L</i>. <i>adelphe</i> <b>sp. nov.</b> is much narrower than in <i>Paraleucothoe</i>. <b>Distribution.</b> <i>Australia</i>. Queensland: Yonge Reef and Horseshoe Reef, Lizard Island (current study).
description: Published as part of <i>White, Kristine N. &amp; Thomas, James Darwin, 2009, Leucothoidae *, pp. 494-555 in Zootaxa 2260 (1)</i> on pages 498-501, DOI: 10.11646/zootaxa.2260.1.29, http://zenodo.org/record/5323471
description: {"references": ["Barnard, J. L. (1965) Marine Amphipoda of atolls in Micronesia. Proceedings of the United States National Museum, 117, 459 - 551.", "Schellenberg, A. (1938) Littorale amphipoden des Tropischen Pazifics. Kungliga Svenska Vetenskapsakademiens Handlingar, 16 (3), 1 - 105.", "Thomas, J. D. &amp; Klebba, K. N. (2006) Studies of commensal leucothoid amphipods: Two new sponge-inhabiting species from South Florida and the Western Caribbean. Journal of Crustacean Biology, 26, 13 - 22.", "Walker, A. O. (1904) Report on the Amphipoda collected by Professor Herdman at Ceylon in 1902. Ceylon Pearl Oyster Fisheries of the Gulf of Manaar, Supplementary Report, 17, 229 - 300."]}