Association between Hyperoche martinezii (Amphipoda: Hyperiidae) and ctenophores from the Buenos Aires coast, Argentina (South-western Atlantic Ocean)

PUENTE TAPIA F; DIAZ BRIZ L.; SCHIARITI A.; GASCA R.; GENZANO G. N.

MARINE BIOLOGY RESEARCH

TAYLOR & FRANCIS AS

Lugar: Londres; Año: 2016

1745-1000

This survey examined the association between the hyperiid amphipod Hyperoche martinezii andctenophores off the Argentinian coasts (38°08′17′′S, 57°31′18′′W) through the evaluation ofseasonality, prevalence and intensity of infection during an annual cycle. Medusae were alsoexamined but only the ctenophores Mnemiopsis leidyi, Pleurobrachia pileus and Beroe ovatashowed this association during the austral mid-spring to mid-summer. A total of 502hyperiids were obtained; most (422 individuals) were larval stages, 53 juveniles and 27adults. Mnemiopsis leidyi had the highest number of hyperiids with the 98.6%, followed byP. pileus (0.80%), and B. ovata (0.60%). Total prevalence was 2.0 and intensity of infectionranged between 1?17 hyperiids per ctenophore. The host with highest prevalence wasB. ovata (4.54), followed by M. leidyi (3.76) and P. pileus (0.1). Prevalence values had somecorrelations with the increase in the total length of B. ovata (r = 0.480, P = 0.006) and M. leidyi(r = 0.501, P < 0.001), and between total length and intensity in B. ovata (r = 0.425, P = 0.017).The hyperiid was found in different parts of the host body: larval stages were found in thecanal close to the subtentacular comb row and the stomodeum, whereas juvenile/adultstages were observed with a resting posture on the external surface of the ctenophores. Theknown geographic distribution of H. martinezii was extended; this finding represents theaddition of three new hosts for this hyperiid.