Hyachelia lowryi, Serejo & Sittrop, 2009

Serejo, Cristiana S. & Sittrop, Daniela J., 2009, Hyalidae *, Zootaxa 2260 (1), pp. 440-452 : 441-444

Hyachelia lowryi sp. nov.

( Figs 1 , 2 )

Type material. Male, holotype 7.5 mm, QM W28860, Mon Repos , Queensland, Australia (~ 24°48’S 152°26’E), on loggerhead turtle Caretta caretta ( Linnaeus, 1758) , C. Limpus, 1975-1976. Paratypes: female, 5.2 mm, QM W28861, same station data; male, 7.5 mm, AM P80162, same station data; 45 males and 7 females, QM W28862, same station data; 2 males, 1 female, AM P80163, same station data; 4 males (3.3–4.8 mm) and 7 females (3.2–4.4 mm), QM W7387 , Heron Island, Queensland, Australia (~ 23°27’S 151°55’E), from turtle, C. Limpus & R. Monroe, July 1975 ; 4 males (7.1–7.7 mm) and 5 females (8.2–8.6 mm), QM W7393 , Heron Island , Queensland, Australia (~ 23°27’S 151°55’E), on green turtle Chelonia mydas, C. Limpus , 10 July 1975 .

Type locality. Mon Repos, Queensland, Australia (~ 24°48’S 152°26’E) (on loggerhead turtle, Caretta caretta ).

Etymology. The name of the species is in honor to Dr Jim Lowry (Australian Museum), a great amphipod specialist, a good friend, and also one of the organizers of the Lizard Island workshop and consequently editor of this book.

Description. Male, holotype, 7.5 mm, QM W28860.

Head. Head eyes present, well developed, round. Antenna 1 slightly longer than peduncle of antenna 2. Antenna 2 short, not surpassing pereonite 2, peduncle slender, flagellum with 9 articles. Upper lip distally setose. Lower lip with distal and inner margin densely setose. Mandible right with bifid lacinia; left lacinia 5– 6 dentate. Maxilla 1 palp 1-articulate, reaching the base of setal-teeth of outer lobe. Maxilliped palp with long, whip-like apical seta, about 4 x article 4 length.

Pereon. Gnathopods 1–2 distinctly different in size. Gnathopod 1 subchelate; coxa about as long as broad, narrowing distally and distinctly smaller than subsequent coxae; propodus palm transverse, dactylus shorter than palm. Gnathopod 2 subchelate; coxa subquadrate; carpus not projecting between merus and propodus, without setae on the posterior margin; palm extremely acute, parallel to anterior margin and with robust setae all over its extension; dactylus about as long as palm. Coxae 1–4 lacking posterior process. Coxa 2–4 longer than wide; coxa 4 wider than long. Pereopods 3–7 prehensile, propodus with 7 distal robust setae in a sequence; dactylus lacking seta on inner margin. Pereopod 7 basis about as long as broad.

Pleon. Epimeron 3 posterior margin smooth, posteroventral corner subquadrate. Uropod 1 peduncle without enlarged distal robust seta. Uropod 3 peduncle narrowing distally, with a distal robust seta. Uropod 3 lacking rami. Telson cleft, much wider than long.

Female (sexually dimorphic characters). Based on female, 5.2 mm QM W28861. Maxilliped palp with short apical seta, slightly longer than article 4. Gnathopods 1–2 subequal in size and similar; carpus projecting between merus and propodus; palm nearly transverse. Oostegite 2 subtriangular with about 42 setae, oostegite 3 trapezoidal with about 59 setae, oostegite 4 half circle-shaped with about 52 setae, oostegite 5 elongated, narrow with about 34 setae.

Habitat. Ectocommensal on sea-turtles.

Remarks. Besides some important characters discussed at a generic level that also can be used to distinguish H. lowryi sp. nov. from H. tortugae , such as the palp of maxilla 1 reaching the base of outer lobe setal-teeth (vs vestigial) and the whip-like seta of the male palp of maxilliped (vs. short seta), other differences were noticed. Coxa 4 is wider, about 1.2 x wider than long (vs. as long as wide); propodus of pereopods 3–7 with 7 robust setae (vs 4 robust setae); and the inner ramus of uropods 1–2 with 4–5 setae (vs. lacking setae).

Distribution. Australia. North-eastern Queensland (current study).

Figures

FIGURE 1. Hyachelia lowryi sp. nov., holotype, male, 7.5 mm, QM W28860, Mon Repos, Queensland.

FIGURE 2. Hyachelia lowryi sp. nov., paratype, female, 5.2 mm, QM W28861, Mon Repos, Queensland.