Nuuanu quintalana, Hughes, L. E. & Bopiah, A., 2013

Hughes, L. E. & Bopiah, A., 2013, New species of Nuuanu (Amphipoda: Nuuanuidae) from Norfolk Island, Torres Strait and the Cocos (Keeling) Islands, Zootaxa 3641 (2), pp. 165-176 : 167-170

Nuuanu quintalana sp. nov.

( Figs 2–4 )

Type material. Holotype male, 3.7 mm, dissected, 4 slides, AM P.90042; paratype, female, 3.2 mm, dissected, 1 slide, AM P.90043; paratype, male, SEM pin mount, AM P.89312; paratype, male, dissected 4 slides, AM P.90045; paratypes, 17 specimens, AM P.90046, Fig Valley Reef, Norfolk Island (29°03'20"S 167°55'44"E), 18.5 m, coral rubble with algal tufts and sediment, 19 May, 2008, coll. R.T. Springthorpe (MI NFK 67).

Additional material examined. Norfolk Island: 9 specimens, AM P.90047, Emily Bay (29°03'36"S 167°57'12"E), 3.7 m, airlift, rubble on sand, 20 May, 2008, coll. R.T. Springthorpe (MI NFK 82); 4 specimens, AM P.90048, Duncombe Bay (29°03'30"S 167°57'13"E), 16 m, airlift, coral rubble, 13 May, 2008, coll. R.T. Springthorpe (MI NFK 19); 1 specimen, AM P.90049, near Anson Point, Gun Club reef (29°00'25"S 167°54'45"E), 14.6 m, airlift, coral rubble on sand, 17 May, 2008, coll. R.T. Springthorpe (MI NFK 62); 33 specimens, AM P.90050, Phillip Island, East of Sail Rock (29°06'55"S 167°57'31"E), 13 m, airlift, under stones, 14 May, 2008, coll. R.T. Springthorpe (MI NFK 22); 3 specimens, AM P.90051, Swiss cheese Reef (29°00'23"S 167°56'50"E), 16.6 m, airlift, coral rubble, 15 May, 2008, coll. R.T. Springthorpe (MI NFK 36); 5 specimens, AM P.90052, Phillip Island, East of Sail Rock (29°06'55"S 167°57'31"E), 14.8 m, airlift, under stones, rubble, 14 May, 2008, coll. R.T. Springthorpe (MI NFK 20); 3 specimens, AM P.90053, Duncombe Bay (29°03'30"S 167°57'13"E), 15 m, 13 May, 2008, coll. Dr. J.K. Lowry (MI NFK 13); 1 specimen, AM P.90054, Emily Bay (29°03'36"S 167°57'12"E), 4 m, tubes and rubble with encrusting algae, 20 May, 2008, coll. Dr. J.K. Lowry (MI NFK 87); 3 specimens, AM P.90055, Cathedral Rock (29°00'13"S 167°56'57"E), 10.9 m, airlift, under stones, 13 May, 2008, coll. R.T. Springthorpe (MI NFK 7).

Type locality. Fig Valley Reef, Norfolk Island, Tasman Sea.

Etymology. Named for the Quintal family of Norfolk Island, in gratitude for their long-term encouragement to the academic pursuits of the first author.

Diagnosis. Antenna 1 peduncular article 1 with 1 distoventral robust seta; article 2 not geniculate. Gnathopod 2 propodus subovoid, facial surface with dense slender setae proximally, propodus palm acute, margin undulating (with nodules) defined by 7 robust setae with weak distal shelf; dactylus long, 0.5 times length of propodus. Pereopod 5–6 length greater than pereopod 7; basis posterior margin convex proximally, excavate distally.

Pleonites 1–2 dorsum smooth. Epimera 1–3 posterior margin straight, corner broadly rounded. Urosomite 1 without carina. Uropod 2 inner ramus longer than peduncle. Uropod 3 outer ramus without lateral robust setae.

Description. Based on holotype male, 3.7 mm, AM P.90042.

Head lateral cephalic lobe apically acute, with anteroventral slit; anteroventral corner subquadrate. Eyes poorly developed, ommatidia separated. Antenna 1 longer than antenna 2; peduncular article 1 subequal to article 2 with 1 distoventral robust seta; article 2 not geniculate, longer than article 3; primary flagellum with 12 articles; accessory flagellum 4-articluate. Antenna 2 peduncular article 2 produced dorsodistally; article 4 longer than article 5; flagellum with 9 articles. Mandible molar well-developed triturative; accessory setal row with 7 setae; palp article 1 twice as long as broad; article 3 linear, subequal in length to article 2.

Pereon. Gnathopod 1 merus posterodistal corner acute; carpus 1.5 times as long as propodus; propodus palm defined by 3 bifurcating setae. Gnathopod 2 merus subquadrate to rounded distoventrally; carpus twice as long as broad, lobate, projecting between merus and propodus; propodus subovoid, facial surface with dense slender setae proximally, posterior margin weakly convex, propodus palm acute, margin undulating (with 5 nodules) defined by 5 robust setae, weak distal shelf with 2 robust setae; dactylus long, 0.5 times length of propodus. Pereopod 3 coxa subequal in length to coxa 2. Pereopod 4 coxa posteroventral lobe well-developed, subquadrate. Pereopod 5–6 length greater than pereopod 7; basis posterior margin convex proximally, excavate distally, castellate. Pereopod 7 basis posterior margin convex, castellate.

Pleon. Pleonites 1–2 dorsum smooth. Epimera 1–3 posterior margin straight, corner broadly rounded. Urosomite 1 without carina. Uropod 1 peduncle with 1 basofacial robust seta; inner ramus subequal to outer ramus in length, longer than peduncle. Uropod 2 inner ramus subequal to outer ramus length, longer than peduncle. Uropod 3 inner ramus short, 0.5 times length of outer ramus; outer ramus 2-articulate, length 1.5 times breadth, without lateral robust setae; article 2 short, as long as broad. Telson as long as broad, deeply cleft (greater than 66%), each lobe with 1 apical robust seta.

Female, sexually dimorphic characters. Based on paratype 3.2 mm, AM P.90043.

Pereon. Gnathopod 1 propodus palm with 2 bifurcating robust setae. Gnathopod 2 carpus longer than propodus; propodus rectolinear, subchelate, palm straight, defined by corner with 2 robust setae; dactylus reaching to the end of the palm.

Remarks. Nuuana quintalana sp. nov. and N. titaseyi sp. nov. differ from other Nuuanu species by the male gnathopod 2 propodus subovoid with dense tuft of slender setae on the facial surface confined to the proximal portion of the article and palm lined with robust setae. In N. quintalana the gnathopod 2 propodus palm has prominent nodule which were not observed in N. titaseyi , both species where of similar size indicating this character is less likely to be an artefact of growth stage.

Nuuanu quintalana has a smooth dorsum which differentiates it from N. titaseyi which has pleonites 1–2 with a dorsodistal spine. Nuuanu quintalana differs further from N. titaseyi in the straight antennae 1 with a single robust seta on the peduncle article 1 ventral margin and accessory flagellum with 4 articles, while the latter species has a geniculate antennae 1 with two setae and 3-articluate accessory flagellum, respectively.

Distribution. Norfolk Island, Tasman Sea (current study).

Figures

FIGURE 2. Nuuanu quintalana sp. nov., male, AM P. 89312, 3.5 mm, Fig Valley Reef, Norfolk Island, Tasman Sea. SEM photographs: (A) head lateral view (scale 100 µm); (B) pereopod 7 lateral view (scale 100 µm); (C) whole animal lateral view (scale 100 µm); (D) whole animal dorsal view (scale 200 µm); (E) telson and uropod 3 dorsal view (scale 100 µm); and (F) urosome dorsal view (scale 100 µm).

FIGURE 3. Nuuanu quintalana sp. nov., holotype male, AM P. 90042, 3.7 mm, Fig Valley Reef, Norfolk Island, Tasman Sea (scales represent 0.1 mm, except telson 0.05 mm).

FIGURE 4. Nuuanu quintalana sp. nov., paratype female, AM P. 90043, 3.2 mm, Fig Valley Reef, Norfolk Island, Tasman Sea (scales represent 0.1 mm).