Hemiaegina minuta Mayer 1890

Hemiaegina minuta Mayer, 1890

(Fig. 3)

Hemiaegina minuta Mayer, 1890: 40, pl. 1: fig. 25, pl. 3: figs 32–35, pl. 5: fig. 52, pl. 6: figs 13, 33–34, pl. 7: fig. 4. — McCain, 1968: 61, figs 29–30. — McCain & Steinberg, 1970: 51. — Gable & Lazo-Wasem, 1987: 637. — Müller, 1990: 836. — Serejo, 1997: 630, fig. 1. — Guerra-García, 2003a: 105, fig. 10. — Guerra-García 2003b: 6, fig. 3; Guerra-García, 2004a: 39, fig. 32. — Díaz et al., 2005: 5, 6, 18, fig. 9. — Krapp-Schickel & Guerra-García, 2005: 50, fig. 3. —Guerra-García, 2006: 443, fig. 43. — Guerra-García, Krapp-Schickel & Müller, 2006: 171, figs 14–16.

Hemiaegina quadripunctata Sundara Raj, 1927: 126, pl. 18.

Hemiaegina costai Quitete, 1972: 165, pls. 1–2.

Material examined. 5 males, 2 females, AM P61648 (QLD 979). See station list for occurrences (Lowry & Myers 2009) and Guerra-García (2006) for complete material examined.

Type locality. Off Amoy, China, 15–46 m depth.

Description. Based on male, AM P61648.

Head and pereonites slender. Head/pereonite 1 fused (suture absent); dorsal margin straight; eye small, not distinctive. Antenna 1 well developed; slender, 0.8 x body length; peduncle article 2 longest, article 3 straight; accessory flagellum absent; flagellum longer than peduncle, with more than 2 articles, proximal article composed of 2 articles. Antenna 2 0.4 x antenna 1 length, slender; peduncle with several feeble setae; flagellum about 1/5 (0.2 x) of peduncular length, with 2 articles. Mandible right incisor with 5 teeth, right lacinia mobilis transformed into a serrated plate, accessory setal row absent; molar well developed; left incisor with 5 teeth, lacinia mobilis with 5 teeth, without trapezoid plate; palp absent. Maxilla 1 outer plate with 6 stout apical setal-teeth. Maxilliped inner plate smaller than outer plate, quadrilateral; outer plate 2 x length of inner plate; palp article 2 setose on inner margin; palp article 4 not enlarged.

Pereon. Pereonites 2 to 7 not fused. Pereonite 1 without projections. Gnathopod 1 distinctly smaller than gnathopod 2; propodus subtriangular, palm begins 1/5 along posterior margin, smooth, with large, rounded knob proximally; dactylus curved, inner margin smooth. Pereonite 2 without anterolateral projection, with ventral projection between insertion of gnathopods. Gnathopod 2 situated toward anterior end of pereonite 2 or near middle of pereonite 2; basis about 1.5 x length of pereonite 2, without anterodistal projection; ischium without anterodistal projection; propodus elliptical, massive, anterodistal margin widely concave, without anterodistal triangular projection or projections along mid-anterior margin; palm without proximal cavity filled with membranous sack, palm proximal projection with 1 robust (grasping) seta, palm margin irregular, smooth, without hook-like projection at base of dactylus, with broad well developed distal shelf, with two triangular projections distally, with deep, wide sinus, with large midpalmar projection. Pereonite 3 without projections. Pereopod 3 reduced or vestigial, with 1 article. Pereonite 4 without projections. Pereopod 4 reduced, with 1 article. Pereopod 5 well developed, with 6 articles, slender. Pereopods 6 and 7 prehensile. Pereopod 6 basis longest followed by merus. Pereopod 7 similar to pereopod 6; merus shorter than basis.

Gills on pereonites 3 and 4. Pereonite 3 gill length about as long as corresponding pereonite, straight, ovate or elongate, cylindrical. Pereonite 4 gill as long as corresponding pereonite, straight, ovate or elongate, cylindrical.

Pleon. Uropod 1 present; peduncle free, elongate, length about 1.7 x width; ramus length about 3–4 x width, ramus 1.75 x peduncular length.

Female not described (similar to male).

Habitat. This species has been found on many different substrates on the Great Barrier Reef: green, brown and red algae, sponges, tunicates, seagrass, dead corals encrusted with algal turf, and under small boulders, but at Lizard Island the species has been only found on hydroids (Guerra-García 2006). Hemiaegina minuta has been previously collected from Sargassum sp. and taken in plankton tows (McCain & Steinberg 1970). Müller (1990) reported that H. minuta prefers more or less exposed reef locations. Guerra-García (2003a; 2003b) found the species associated with algae in Papua New Guinea and Mauritius. This species has also been found on Arca zebra (Díaz et al. 2005).

Remarks. Hemiaegina minuta is widely distributed in tropical and temperate waters worldwide (Müller 1990). The Queensland specimens agree with the description of McCain (1968) based on material from the West coast of North America.

Distribution. Australia. Queensland: Freshwater Bay; Stradbroke Island; GBR: North Point, Lizard Island. Dome Island, Hervey Islands; East Fitzroy Reef, Great Barrier Reef. New South Wales: Elizabeth and Middleton Reef; Lord Howe Island (Guerra-García 2006). Western Australia: Fremantle (Guerra-García 2004a). Bermuda (McCain & Steinberg 1970). China. Off Amoy, China, 15–46 m deep (Mayer 1890). Colombia. Bahía de Santa Marta, Punta Betín, Bahía Concha, Bahía Nenguangue (Guerra-García et al. 2006). India. Krusadai Island, South Arabian coast (McCain & Steinberg 1970). Indonesia. Bali (Krapp-Schickel & Guerra-García 2005). Japan. Sunohama and Tateyama (McCain & Steinberg 1970). Mauritius. Baie du Tumbeau (Guerra-García 2003b). Papua New Guinea. Bootless Bay (Guerra-García 2003a). Society Islands. Bora Bora (McCain & Steinberg 1970). South Africa. False Bay (McCain & Steinberg 1970). USA. Virginia; Cape Hatteras, North Carolina; Elliot Key, Florida; Loggerhead Key, Tortugas; 29º44’N 88º23.5’W; Port Aransas, Texas; St. John, Virgin Islands; Oahu, Hawaii (McCain & Steinberg 1970). Venezuela. Guayacán, Sucre (Díaz et al. 2005).