Hyachelia lowryi Serejo and Sittrop, 2009

Iwasa-Arai, Tammy, Andrade, Sónia C. S., Miguel, Camila, Siqueira, Silvana G. L., Werneck, Max Rondon, Leite, Fosca P. P., Moraes, Lara, Santos, Marcelo Renan D., Medeiros, Luciana S., Lopes, Uylia H. & Serejo, Cristiana, 2023, Tuerkayana latens Ng and Hsi-Te Shih 2023, n. sp., Zoological Studies 62 (54), pp. 1-12 : 5

Hyachelia lowryi Serejo and Sittrop, 2009 ( Figs. 1 and 2 )

Hyachelia lowryi Serejo and Sittrop, 2009: 441–444 , figs. 1–2; Yabut et al. 2014: 5–6, figs. 1B, 5B, 6.

Material examined: 5 males, Feliz Deserto, Alagoas, Brazil (10°17'59.0"S, 36°17'25.6"W), ZUEC CRU 4385; 13 males, 9 females and 4 juveniles, Arembepe, Bahia, Brazil (12°45'54.8"S, 38°10'11.5"W).

Distribution: Type locality: Mon Repos, Queensland, Australia (~ 24°48'S, 152°26'E), on loggerhead turtle Caretta caretta (Linnaeus, 1758) and green turtle Chelonia mydas (Linnaeus, 1758) ( Serejo and Sittrop 2009) . Palmyra Atoll National Wildlife Refuge (5°53'N, 162°5'W), on C. mydas ( Yabut et al. 2014) . Atlantic Ocean: Feliz Deserto, Alagoas (10°17'59.0"S, 36°17'25.6"W), Brazil, on hawksbill turtle Eretmochelys imbricata (Linnaeus, 1766) (present study) ( Fig. 2 ). Arembepe, Bahia (12°45'54.8"S, 38°10'11.5"W), Brazil, on C. caretta (present study).

Remarks: The genus Hyachelia presents two species, Hyachelia lowryi and H. tortugae that are obligate commensals of marine turtles. Hyachelia lowryi is very distinct from H. tortugae and the Brazilian material displayed the overall morphology of the original description from Queensland, Australia provided by Serejo and Sittrop (2009). Differences between H. lowryi and H. tortugae (in parentheses) are: palp of maxilla 1 reaching the base of outer lobe setalteeth (vs vestigial); presence of a long whip-like seta on the male palp of maxilliped (vs short seta); coxa 4 wider, about 1.2x 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) ( Serejo and Sittrop 2009). Previous records from the Palmyra Atoll National Wildlife Refuge reported both Hyachelia species, H. lowryi and H. tortugae on green turtles ( Chelonia mydas ), where they can co-occur in the same turtle host ( Yabut et al. 2014). In our study, H. lowryi were absent on the sampled green turtles. This is the first record of H. lowryi on a hawksbill turtle [ Eretmochelys imbricata (Linnaeus, 1766) ], as well as the first observation in the Atlantic Ocean for both hawksbill and loggerhead turtles.

Figures

Fig. 1. a, Hawksbill turtle (Eretmochelys imbricata) stranded in Alagoas, northeast Brazil. b, Amphipods (Hyachelia lowryi) associated to E. imbricata, arrow indicates H. lowryi specimens. c, Hyachelia lowryi Serejo and Sittrop, 2009 (ZUEC CRU 4385). d, Hyachelia tortugae Barnard, 1967 (ZUEC CRU 4386).

Fig. 2. Hyachelia lowryi Serejo and Sittrop, 2009 (ZUEC CRU 4385). a, Maxilliped, scale bar: 0.1 mm. b, Gnathopod 2, scale bar: 1.0 mm. c, Uropod 3, scale bar: 0.1 mm. d, Gnathopod 1, scale bar: 0.5mm; e) Uropod 1, scale bar: 0.5 mm. f, Pereopod 4, scale bar: 0.5 mm. g, Pereopod 7, scale bar: 0.5 mm; h) Uropod 2, scale bar: 1.0 mm.