Cymadusa heronensis Peart 2007
Creators: name: Hughes, L. E.
name: Lowry, J. K.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Amphipoda
Ampithoidae
Cymadusa
Cymadusa heronensis

description: <i>Cymadusa heronensis</i> Peart, 2007 (Figs 15, 16) <i>Cymadusa heronensis</i> Peart, 2007a: 13, figs 8–11. <b>Material examined</b>. Holotype, male, 4 mm, AM P61906 (QLD 1343); 7 unsexed, AM P75511 (QLD 1318); 8 unsexed, AM P75511 (QLD 1318); 6 unsexed, AM P75512 (QLD 1326); 6 unsexed, AM P75513 (QLD 1326); 3 unsexed, AM P75514 (QLD 1329); many unsexed, AM P76753 (QLD 1938); 2 unsexed, AM P76755 (QLD 1941); 1 unsexed, AM P76754 (QLD 2006). <b>Type locality.</b> Northern reef flat, Heron Reef, Heron Island, Queensland, Australia (23º27’S 151º55’E), living on <i>Sargassum</i> sp., 0.5 m. <b>Description.</b> Based on holotype, male, 4 mm, AM P61906. <b>Head.</b> <i>Head</i> as long as deep. <i>Antenna 1</i> longer than antenna 2; peduncular article 1 subequal to article 2; flagellum 20 articles; accessory flagellum with 1 article. <i>Antenna 2</i> peduncle not densely setose on ventral margin; article 4 longer than article 5; flagellum 9 articles. <i>Upper lip</i> directed nearly straight down, lateral margins each with midlateral notch. <i>Mandible</i> molar well developed, triturating, accessory setal row with 5 serrate setae; palp 3–articulate, apically setose; article 1 shorter than article 2; article 2 longer than article 3; article 3 longer than article 1. <i>Lower lip</i> outer plates notched, forming a deep distal cleft, lateral lobe distinctly longer than medial lobe; mandibular lobe with curved margins, rounded apically. <i>Maxilla 1</i> inner plate with 1 seta; palp article 2 broad. <i>Maxilla 2</i> inner plate narrower than outer plate. <i>Maxilliped</i> outer plate with row of large robust setae along medial margin. <b>Pereon.</b> <i>Coxae 1–4</i> deeper than broad. <i>Gnathopod 1</i> smaller than gnathopod 2; coxa subequal to coxa 2, slightly produced, anterior margin straight, anteroventral corner subacute, with row of slender setae of varying length along ventral margin; basis subequal to coxa in length, anterodistal lobe rounded, with 1 slender seta; merus posterodistal lobe acute; carpus about as long as broad, shorter than propodus, anterior margin with slender setae, posterior margin subacute; propodus broad, subtriangular; palm acute, sinusoidal, with subquadrate posterodistal corner, with 1 robust seta defining palm; dactylus subequal in length to palm, inner margin crenate. <i>Gnathopod 2</i> coxa with row of slender setae of varying length along ventral margin; basis with sparse slender setae, anterodistal corner with 1 slender seta; merus margin with short, subacute anterodistal lobe; carpus shorter than propodus, cup-shaped; propodus broad, less than 1.5 x as long as broad, subovoid, not produced into an anterodistally setose lobe, anterior margin with fringe of slender setae; palm acute, excavate, with subquadrate posterodistal corner, without defining palm robust seta; dactylus subequal in length to palm, tapering evenly, apically acute, inner margin crenate. <i>Pereopods 3–4</i> basis narrow; merus subequal in length to carpus. <i>Pereopods 5–7</i> weakly prehensile. <i>Pereopod 5</i> without medial slender setae; distal articles broad; propodus slightly expanded distally, with 2 anterodistal striated robust setae; dactylus strongly curved. <i>Pereopod 6</i> basis posterior margin rounded, with a single marginal robust seta; distal articles slender; propodus slightly expanded distally, with 3 anterodistal striated robust setae; dactylus strongly curved. <i>Pereopod 7</i> similar to pereopod 6. <b>Pleon.</b> <i>Epimera 2–3</i> posteroventral corner narrowly rounded. <i>Uropod 1</i> peduncle with 7 robust setae, with long fringe of slender setae (greater than 0.5 x length of peduncle), with large, acute distoventral spine; outer ramus with 3 lateral robust setae; inner ramus with 2 lateral robust setae;. <i>Uropod 2</i> peduncle with 2 robust setae; outer ramus with 2 marginal robust setae; inner ramus with 3 marginal robust setae. <i>Uropod 3</i> peduncle longer than broad, less than 2 x length of rami, without marginal slender setae, with 3 distal robust setae, with 5 distal slender setae; outer ramus with 2 weakly curved distal robust setae, without lateral robust or slender setae; inner ramus with 5 distal slender setae, without lateral robust setae. <i>Telson</i> subtrapezoidal, apically truncated, with small apical cusp on each distolateral corner, with 2 pair of apical slender setae and with 2 pair of lateral and 1 pair of apical plumose setae. <b>Female</b> (sexually dimorphic characters). Based on paratype, female, 4 mm, AM P61907. <i>Gnathopod 1</i> subequal in size to gnathopod 2; basis subequal in length to coxa, anterodistal lobe absent; carpus posterior margin convex; propodus subovoid; palm convex, with rounded corner. <i>Gnathopod 2</i> palm sinusoidal, with 1 robust seta defining palm. <b>Habitat.</b> Brown algae <i>Dictyota</i> sp., <i>Padina</i> sp., <i>Sargassum</i> sp. and Green alga <i>Caulerpa</i> sp. <b>Remarks</b>. <i>Cymadusa heronensis</i> is very similar to <i>C. aungtonyae</i> Peart, 2002 from Thailand and <i>C. thagaay</i> Peart, 2007a from the northern end of the GBR. <i>Cymadusa aungtonyae</i> can be differentiated by mandibular palp article two which has a dense cluster of setae, absent in the two GBR species. <i>Cymadusa heronensis</i> and <i>C. thagaay</i> are also similar to <i>C. mauritiensis</i> (Ledoyer, 1978) though the later species has less setae along the male gnathopod 2 carpus and propodus anterior margin. The lateral cephalic lobe in <i>C. heronensis</i> and <i>C. thagaay</i> is rounded while in <i>C. mauritiensis</i> it is truncate. The more heavily calcified broadly rounded propodus shape and absence of the distal robust setae on the palm of male gnathopod 2 distinguishes <i>C. heronensis</i> from <i>C. thagaay</i> which has gnathopod 2 propodus margins straight and palm with a distal robust seta. <b>Distribution.</b> <i>Australia</i>. Queensland: Heron Island (Peart 2007a, current study); One Tree Island (current study).
description: Published as part of <i>Hughes, L. E. &amp; Lowry, J. K., 2009, Ampithoidae *, pp. 153-219 in Zootaxa 2260 (1)</i> on pages 178-181, DOI: 10.11646/zootaxa.2260.1.8, http://zenodo.org/record/5322208
description: {"references": ["Peart, R. A. (2007 a) A review of Australian Cymadusa (Crustacea: Amphipoda: Ampithoidae) with descriptions of eight new species. Zootaxa, 1540, 1 - 53.", "Peart, R. A. (2002) New species of Ampithoidae (Crustacea, Amphipoda, Corophioidea) from the eastern Andaman Sea. Phuket Marine Biological Center Special Publication, 23 (1), 229 - 252."]}