Caprella penantis Leach, 1814

Guerra-García, José M. & Lowry, J. K., 2009, Caprellidae *, Zootaxa 2260 (1), pp. 290-327 : 293-294

Caprella penantis Leach, 1814

( Fig. 2 )

Caprella Penantis Leach, 1814: 404 .

Caprella acutifrons Mayer, 1882: 48 . — Mayer, 1890: 50, pl. 2: figs 36, 37, 39–41, pl. 4: figs 52, 53, 55, 57–61, 65–69. — Mayer, 1903: 79, pl. 3, figs 4–28, pl. 7, figs 62–65.

Caprella penantis McCain, 1968: 33 , figs 15, 16. — McCain & Steinberg, 1970: 33. — Cavedini, 1982: 508. —Krapp- Schickel, 1993: 791. — Guerra-García & Takeuchi, 2002: 692 , fig. 12. — Guerra-García & Takeuchi, 2004: 1013, fig. 35. — Guerra-García, 2004a: 30, 32, 33, fig. 32. — Krapp-Schickel & Guerra-García, 2005: 49, fig. 2. —Guerra- García, 2006: 442, fig. 42. — Guerra-García, Krapp-Schickel & Müller, 2006: 153 , figs 2–4.

Material examined. 4 males, 1 premature female, 3 females, 1 juvenile, AM P61632 ( QLD 658 ) ; 1 male, 1 premature female, 1 female, 1 juvenile, AM P61631 ( QLD 659 ) .

Type locality. Devonshire Coast , England .

Description. Based on male, 14 mm, AM P61632.

Head and pereonites slender. Head/pereonite 1 fused (suture present); dorsal margin straight; eye large, distinctive. Antenna 1 well developed; slender, 0.4 x body length; peduncle article 2 longest, article 3 straight; accessory flagellum absent; flagellum subequal in length to peduncle, with more than 2 articles. Antenna 2 0.75 x antenna 1 length, slender; peduncle setose; flagellum 0.4 x peduncular length, with 2 articles. Mandible right incisor with 5 teeth, right lacinia mobilis with 5 indistinct teeth, accessory setal row with 2 setae; molar well developed; left incisor with 5 teeth, lacinia mobilis with 5 teeth, without trapezoid plate, accessory setal row with 3 setae; palp absent. Maxilla 1 outer plate with 7 stout apical setal-teeth. Maxilliped inner plate subrectangular; palp article 4 not enlarged.

Pereon. Pereonites 2 to 7 not fused; pereonites 3 and 4 longest, subequal in length (just about longer than other pereonites). Pereonite 1 without projections. Gnathopod 1 distinctly smaller than gnathopod 2; propodus subtriangular, palm begins 1/6 along posterior margin, minutely serrate, without large, rounded knob proximally; dactylus slightly curved, inner margin smooth. Pereonite 2 without projections. Gnathopod 2 situated toward anterior end of pereonite 2; basis about 0.5 x length of pereonite 2, basis without anterodistal projection; ischium without anterodistal projection; propodus subovate or elliptical, massive, anterodistal margin slightly convex or straight, without anterodistal triangular projection, without projections along midanterior margin; palm without proximal cavity filled with membranous sack, palm with proximal poison tooth, margin deeply concave, smooth, without hook-like projection at base of dactylus, with broad well developed distal shelf, without projection, without sinus, without midpalmar projection. Pereonite 3 without projections. Pereopod 3 absent. Pereonite 4 without projections. Pereopod 4 absent. Pereopod 5 well developed, with 6 articles, broad. Pereopod 6 basis shorter than propodus.

Gills on pereonites 3 and 4. Pereonite 3 gill length about 1/2 of corresponding pereonite, straight, ovate. Pereonite 4 gill length about 1/2 of corresponding pereonite, straight, ovate.

Pleon. Unknown.

Female (sexually dimorphic characters) based on female, 12 mm, AM P61632. Gnathopod 2 propodus large; palm margin slightly convex, without distal shelf.

Habitat. The material on the Great Barrier Reef was found clinging to Halimeda . Caprella penantis has also been found living on red and brown algae, Posidonia , hydroids, Alcyonaria, Zoantharia, Bryozoa, sponges, Arbacia (Echinodermata) and Libinia (Decapoda) ( Krapp-Schickel 1993). The species has been also found in sponges, ascidians, spirorbids, gorgonaceans, Caulerpa beds and hydroid Cnidoscyphus (Guerra- García 2004a; Guerra-García et al. 2006), and among mussels ( Díaz et al., 2005).

Remarks. Although this species is believed to be cosmopolitan ( Krapp-Schickel, 1993), its presence is only occasional along the Great Barrier Reef, occurring in only two samples near the northern end of the reef.

Distribution. Australia. Queensland: GBRMPA Reef 11-131, northern end of the Great Barrier Reef (Guerra-García 2006). Tasmania: Mercury Passage ( Guerra-García & Takeuchi 2004). Other records. Atlantic Ocean, Indian Ocean, Pacific Ocean and Mediterranean Sea (see Krapp-Schickel & Guerra-García 2005).

Figures

FIGURE 2. Caprella penantis Leach, 1814. Lateral view. A, male, ~6 mm; B, female, ~3.3 mm, AM P61632, GBRMPA Reef 11-131, Great Barrier Reef. Refigured from Guerra-García (2006).