Cymadusa hoeyae Hughes & Lowry, 2009

Hughes, L. E. & Lowry, J. K., 2009, Ampithoidae *, Zootaxa 2260 (1), pp. 153-219 : 181-184

Cymadusa hoeyae Hughes & Lowry sp. nov.

( Figs 17 , 18 )

Type material. Holotype, male, 7.5 mm, 1 slide, AM P76761 . Paratype, female, 4 unsexed, AM P71037 , Picnic Beach , Palfrey Island, near Lizard Island (14°41.69’S 145°26.89’E), algal mat and fine sediment from rubble bottom, reef flat, 3 m, S. LeCroy, 27 February 2005 ( QLD 1708 ) .

Additional material examined. 1 dissected male, AM P76764 ( QLD 1704); 1 dissected female, AM P76763 ( QLD 1704); 1 unsexed, AM P76765 ( QLD 1704); 1 unsexed, AM P76766 ( QLD 1730); 5 unsexed, AM P76762 ( QLD 1757).

Type locality. Picnic Beach , Palfrey Island, near Lizard Island, Queensland, Australia (14°41.69’S 145°26.89’E), living on the reef flat in algal mats and fine sediment from rubble bottoms, 3 m.

Etymology. Named for Jessica Hoey (GBRMPA), in appreciation for her help in the organisation of our collecting permits for the GBR project.

Description. Based on holotype, male, 7.5 mm, AM P76761.

Head. Antenna 1 shorter than antenna 2; peduncular article 1 subequal to article 2; flagellum 19 articles; accessory flagellum with 1 article. Upper lip lateral margins each with midlateral notch. Mandible molar well developed, triturating, accessory setal row with 8 serrate setae; palp 3–articulate, article 3 apically setose; article 1 shorter than article 2; article 2 shorter than article 3; article 3 longer than article 1. Lower lip outer plates notched, forming medial excavation, lateral lobe distinctly longer than medial lobe; mandibular lobe with curved margins, rounded apically. Maxilla 1 inner plate with 3 setae; palp article 2 broad. Maxilla 2 inner plate narrower than outer plate. Maxilliped outer plate with row of large robust setae along medial margin.

Pereon. Coxae 1–4 deeper than broad. Gnathopod 1 longer than gnathopod 2; coxa distinctly larger than coxa 2, produced, anterior margin straight, anteroventral corner rounded, with a tuft of long or short slender setae in the posteroventral corner; basis longer than coxa, anterodistal lobe absent, with 1 slender seta; merus posterodistal lobe subacute; carpus about 3 x as long as broad, longer and more narrow than propodus, anterior margin without setae, posterior margin straight; propodus broad, subovoid; palm acute, convex, with rounded posterodistal corner, with 1 robust seta defining palm; dactylus subequal in length to palm, inner margin crenate. Gnathopod 2, coxa with a tuft of slender setae in the posteroventral corner; basis with sparse slender setae, anterodistal corner without setae; merus margin with short, subacute anterodistal lobe; carpus shorter than propodus, cup-shaped; propodus broad, less than 1.5 x as long as broad, subrectangular, not produced into an anterodistally setose lobe; palm acute, sinusoidal, with posterodistal corner, subquadrate, with 1 robust seta defining palm; dactylus subequal in length to palm, tapering evenly, apically acute, inner margin crenate. Pereopods 3–4 basis narrow; merus subequal in length to carpus. Pereopods 5–7 simple. Pereopod 5 without medial slender setae; distal articles slender; propodus not expanded distally, without anterodistal striated robust setae; dactylus strongly curved. Pereopod 6 basis posterior margin straight, with several marginal robust setae; distal articles slender; propodus not expanded distally, without anterodistal striated robust setae; dactylus strongly curved. Pereopod 7 similar to pereopod 6.

Pleon. Epimera 2–3 posteroventral corner with small acute cusp. Uropod 1 peduncle with 8 robust setae, without fringe of long slender setae, with large, acute distoventral spine (half the length of outer ramus); outer ramus length about 5–6 x as long as broad, with 9 lateral robust setae; inner ramus with 9 marginal robust setae;. Uropod 2 peduncle with 4 robust setae; outer ramus with 7 lateral robust setae; inner ramus with 9 lateral robust setae. Uropod 3 peduncle longer than broad, less than 2 x length of rami, without marginal slender setae, with 5 distal robust and 2 distal slender setae; outer ramus with 2 large recurved distal robust setae, with 1 lateral robust seta and 3 lateral slender setae; inner ramus with 3 distal slender setae, with 1 lateral robust seta. Telson subtrapezoidal, apically rounded, with small apical cusp on each distolateral corner, with 2 oblique medial slender setae, with 1 pair of lateral setae, and with 2 pair of lateral and 1 pair of apical plumose setae.

Habitat. Algal mat and fine sediment from rubble bottom.

Remarks. Cymadusa hoeyae sp. nov. belongs to a group of six species with an elongate rectolinear carpus on gnathopod 1 of males and includes: C. brevidactyla ( Chevreux, 1907) ; C. cavimana ( Sivaprakasam, 1971) ; C. filosa Savigny, 1816 ; C. khbarnardi sp. nov. and C. setosa ( Haswell, 1879) .

Cymadusa filosa and C. setosa are distinguished from other members of the group by the densely plumose setae of their gnathopods and from Cymadusa brevidactyla , C. cavimana and C. khbarnardi sp. nov. by the large excavation on the palm of the male gnathopod 2. The sinusoidal palm of the male gnathopod 2 and lack of dense plumose setae along the margins of the gnathopods distinguishes Cymadusa hoeyae from these and all other GBR species.

Distribution. Australia. Queensland: Lizard Island (current study).

Figures

FIGURE 17. Cymadusa hoeyae Hughes & Lowry sp. nov., holotype, male, 7.5 mm, AM P76761, Palfrey Island, Great Barrier Reef.

FIGURE 18. Cymadusa hoeyae Hughes & Lowry sp. nov., holotype, male, 7.5 mm, AM P76761, Palfrey Island, Great Barrier Reef.