Orthoprotella berentsae, Takeuchi, Ichiro & Lowry, James K., 2007

Takeuchi, Ichiro & Lowry, James K., 2007, Redescription of Orthoprotella mayeri K. H. Barnard, 1916 (Crustacea: Amphipoda: Caprellidae) from Cape Province, South Africa and description of O. berentsae sp. nov. from New South Wales, Australia, Zootaxa 1632, pp. 37-48 : 42-46

Orthoprotella berentsae sp. nov.

( Figs. 4–6 )

Orthoprotella sp.— Mayer, 1903: 36, pl. 1 figs. 25–26, pl. 6, figs. 43–44, 46, pl. 9, figs. 15.

Orthoprotella mayeri .— McCain & Steinberg, 1970: 57 (in part).— Lowry & Stoddart, 2003: 27.

Type material. Holotype male, AM P12859 Port Stephens, New South Wales (32°42’S 152°06’E). Paratype: mature female, AM P75895, Port Stephens, New South Wales (32°42’S 152°06’E).

Additional material examined. 4 males, 1 mature female, 1 juvenile, AM P47628, Port Stephens, New South Wales (32°42’S 152°06’E), 1 mature and 1 immature female, AM P47629, Port Jackson, New South Wales (33°51’S 151°16’E), collected prior to 1900. 2 males, 3 mature females, 1 juvenile and fragments, AM P47644, Port Jackson, New South Wales (33°51’S 151°16’E). 1 male, AM P47708, Neutral Bay, Port Jackson, New South Wales (33°50.7’S 151°13.1’E) T. Whitelegge, collected prior to 1900. 2 males, AM P36681, Quarantine Bay, Twofold Bay, New South Wales (37°04.7’S 149°53’E), Posidonia , airlift, 25 June 1985, stn Q8, Q10. 1 immature female, AM P36682, Quarantine Bay, Twofold Bay, New South Wales (37°04.7’S 149°53’E), Posidonia , airlift, 17 September 1985, stn Q1. 1 immature female, AM P36683, Murrumbulga Point, Twofold Bay, New South Wales (37°04.7’S 149°53.1’E), subtidal rock platform, 3 m depth, 9 October 1984, S. Keable, stn Q4.

Description: Holotype male, AM P12859. Head and pereonites slender. Head smooth, not rounded dorsally; eye large, distinctive; head/pereonite 1 slightly concave along dorsal margin; without anterodorsal projections; without anterodorsal projections, without weak anterolateral projection, without anteriorly pointed mid-dorsal and lateral projections, without mid-ventral projections. Antenna 1 robust; 0.6 x body length; peduncle article 2 longest; peduncular article 3 straight; flagellum 0.75 x peduncular length, flagellum with 19–20 articles, proximal article composed of 3 articles. Antenna 2 slender; 0.5 x antenna 1 length; peduncle with several feeble setae; flagellum 1/6 of peduncular length, flagellum with 1 articles.

Labrum notched, forming shallow quadrilateral projections. Mandible right side incisor with 6 teeth; lacinia mobilis with 10 small teeth; accessory setal row with 2 setae; palp article 3 1-15-4-1. Labium finely setose on inner and outer lobes. Maxilla 1 outer plate with 7 stout apical setal-teeth; palp distal margin with 5 triangular projections, each with a slender or robust seta (6 robust setae, a row of slender setae). Maxilliped basal endite (inner plate) oval, with 1 small nodular seta, with 3 setae near distal margin; ischial endite (outer plate) oval, 2 x length of inner plate, inner margin smooth, without many fine setae, with 2 setae on inner margin; palp article 2 setose on inner margin; palp article 3 not expanded, palp article 3 with moderately dense (15–16) distal setae; palp article 4 (dactylus) weakly falcate.

Pereon. Head length 0.64 mm, pereonite 1, 0.64 mm, pereonite 2, 2.25 mm, pereonite 3, 2.96 mm, pereonite 4, 2.66 mm, pereonite 5, 2.25 mm, pereonites 6, 0.64 mm, pereonite 7, 0.56 mm, pereonite 3 longest. Pereonite 2 with anterolateral triangular projection, without midlateral projection, with paired reduced middorsal projections, without paired midventral projections, without dorsodistal projection, without ventral projection between insertion of gnathopods, without acute sternal spine. Pereonite 3 with subacute anterolateral projection, without mid-dorsal projections, without paired midventral projections, without dorsodistal projection. Pereonite 4 with anterolateral projection; without mid-dorsal projections. Pereonite 5 without anterolateral projection, without dorsal projections. Pereonites 6 and 7 not articulated obliquely.

Gnathopod 1 carpus and propodus setose; propodus triangular, with 4 rows of submarginal setae on distal part (near anterior margin), palm begins 1/4 along posterior margin, smooth, with 2 robust setae (one large and one small) near corner of palm, dactylus curved. Gnathopod 2 begins 1/3 (0.3) along posterior margin; coxa vestigial; basis subequal in length to pereonite 2, basis with small projecton near distal margin; ischium with distolateral projection; carpus 0.16 x propodus length; propodus elongate (subrectangular), large, length 2.3 x width, anterodistal margin angled, without dorsodistal triangular projection, without mid-dorsal projections; palm proximal projection with 1 robust (grasping) seta, palm margin convex, smooth, with two triangular projections distally, with large midpalmar spine, with deep, wide sinus, with broad well developed distal shelf, with 3 small projections.

Gill 3 length about 1/3 of corresponding pereonite, curved anteriorly. Pereopod 3 very slender; article 1 length about 4 x width; with 5 distal setae and 1 lateral seta; article 2 tiny, conical. Gill 4 length about 1/2 of corresponding pereonite, curved anteriorly. Pereopod 4 very slender; similar in length to pereopod 3; article 1 length about 4 x width; article 1 with 5 distal setae and 1 lateral seta; article 2 tiny, conical. Pereopods 6 and 7 present. Pereopod 6 basis longest followed by carpus; carpus with 5 setae on anterior margin; propodus with 1 pair of robust setae on anterior margin, propodus with 6 robust setae along palm, propodus without trapezoid comb on distal part of palm; dactylus curved, not setose. Pereopod 7 similar to pereopod 6; merus shorter than basis.

Pleon. Uropod 1 present; peduncle free, elongate, length about 2.5 x width; ramus length 1.5 x width, ramus 0.23 x peduncular length. Uropod 2 ramus absent.

Female (sexually dimorphic characters). Paratype female, body length 7.75 mm, AM P75895. Head smooth, rounded dorsally. Antenna 1 slender; flagellum with 16 articles. Head length 0.52 mm, pereonite 1, 0.31 mm, pereonite 2, 1.55 mm, pereonite 3, 1.71 mm, pereonite 4, 1.19 mm, pereonite 5, 1.53 mm, pereonites 6, 0.52 mm, pereonite 7, 0.42 mm. Gnathopod 1 propodus anterodistal margin slightly angled; palm with deep, narrow sinus. Pereopod 6 basis and propodus subequal in length; carpus with 5 setae on anterior margin; propodus with 1 pair of robust setae on anterior margin, propodus with 5 pairs of robust setae along palm, propodus without trapezoid comb on distal part of palm; dactylus curved, dactylus not setose. Pereopod 7 merus shorter than basis. Uropod 1 absent.

Female "c", body length, 7.57 mm, AM P47629. Pereopod 5 basis merus and carpus, subequal and longest; carpus with 3 setae and a pair of setae on interior face; propodus with a pair of robust (grasping) setae about 1/5 of proximal end on the palm. Pereopod 6 lacking. Pereopod 7 similar to pereopod 5 except propodus longer than merus and carpus, and carpus more setose.

Etymology. This species, berentsae , is named in honour of Dr. P.B. Berents to acknowledge her contribution to the systematics of the Amphipoda in Australia.

Habitat. Marine; recorded from Posidonia .

Distribution. New South Wales: Port Stephens; Broken Bay ( Mayer 1903); Port Jackson; Quarantine Bay and Murrumbulga Point, Twofold Bay.

Remarks. About 20 specimens of O. mayeri (sensu lato) collected from the New South Wales coast are deposited in the Australian Museum. Of them, a male and a female from the “old collection”, recorded as “separated by Steinberg, Reg. No P47601” were identified as the holotype and paratype, since we could not find the specimens collected from Broken Bay that were referred to in Mayer (1903).

The close comparison of the type specimen and other specimens of Orthoprotella mayeri K.H. Barnard, 1916 from South African with specimens of O. mayeri from New South Wales reveals significant differences in the following characters: 1) pereonites 6 and 7 are clearly separated in the New South Wales population, while partially fused in the South Africa population; 2) mandibular palp article 3 lacks a triangular projection in the New South Wales population, which is present in the South African population; 3) the uropod in the New South Wales population has a minute ramus which is shorter than the peduncle, while in the South African population the ramus is longer than the peduncle; 4) in the New South Wales population the notch on the palm of propodus of the gnathopod 2 is wider, and 5) the apical article of antenna 2 is wider than in the South African population. Thus, we describe O. mayeri of New South Wales as O. berentsae sp. nov., based Australian Museum specimens.

Mayer (1903) also reported the occurrence of Orthoprotella sp. from Sydney, Australia and from Singapore in the description of Orthoprotella australis (Haswell, 1879) . Later, K.H. Barnard (1916) described briefly Orthoprotella mayeri as a new species, and treated Mayer's Orthoprotella sp. as the junior synonym of O. mayeri (sensu lato) as mentioned in the remarks. Recently, the occurrences of O. mayeri (sensu lato) were from 440 to 570 m depth off New Caledonia ( Laubitz 1991) and from Lizard Island, Queensland (Guerra- García 2006). Since we have not yet studied the Orthoprotella mayeri (sensu lato) recorded as Orthoprotella sp. from Singapore ( Mayer 1903) and the Orthoprotella mayeri (sensu lato) from New Caledonia ( Laubitz 1991) and Queensland and Elizabeth and Middleton Reefs, New South Wales ( Guerra-García 2006), the distributions of Orthoprotella mayeri (sensu stricto) and O. berentsae in the tropical to subtropical area of Indo- Pacific region are open to the future study.

Figures

FIGURE 4. Orthoprotella berentsae sp. nov., holotype, male, from Port Stephens, New South Wales; a, lateral view; a’, anterior projection on pereonite 2; a’ ’, mid-dorsal projection on pereonite 2; a’ ’’, anterolateral projection on pereonite 3. Female, paratype from Port Stephens, New South Wales; b, female, paratype. Scale 0.10 mm.

FIGURE 5. Orthoprotella berentsae sp. nov., holotype, male, from Port Stephens, New South Wales; a, Flagellum of antenna 2; b, gnathopod 1; c, gnathopod 2; d, pereopod 3; e, pereopod 4, f, urosome (lateral view). Female, paratype; g, gnathopod 2, urosome (lateral view). Female “ c ” from Port Jackson, h, pereopod 5; h’, palm of propodus; i, pereopod 7; i’; palm of propodus. Scale: a, b, d, e, f and h = 0.1 mm, c, d, I and j = 0.5 mm.

FIGURE 6. Orthoprotella berentsae sp. nov., holotype, male, from Port Stephens, New South Wales; a, maxilliped; a’, inner plate of maxilliped; b, right mandible; b’, incisor, lacinia mobilis and finely setose of right mandible; d, maxilla 1. Bars scale 0.1 mm.