Aspects of ecology and biogeography of Acanthocephala in antarctic seabirds

Abstract

SUMMARY. Four species of acanthocephalans are reported from seabirds, nototheniid fishes and gammaridean amphipods in the western Antarctic. Corynosoma hamanni (von Linstow, 1892) was found in Phalacrocorax atriceps King, Chionis alba (Gmelin), Larus dominicanus Lichtenstein, and Catharacta lonnbergi (Mathews). The complete life cycle of this acanthocephalan was elucidated : cysticanths develop in the haemocoel of a gammaridean amphipod, Pontogeneiella sp. of the family Eusiridae and presumably, following ingestion of parasitized amphipods, encyst in the body cavity of antarctic fishes of several species. Corynosoma singularis Skriabin and Nikol'skii, 1971 was found only in P. atriceps. Corynosoma bullosum (von Linstow, 1892) occurred in both P. atri ceps and Pygoscelis papua (Forster). Neither of these species of Corynosoma had previously been reported from avian hosts. Corynosoma shackletoni Zdzitowiecki, 1978 was recorded only as a parasite of P. papua. The first known gravid females of this species were found during this study, indicating that C. shackletoni is a typical parasite of avian, rather than mammalian, final hosts. It is the first acanthocephalan known to typically occur in an avian definitive host in Antarctica. The host-distribution of Corynosoma spp. in birds suggested that these parasites were being acquired from piscine or possibly amphipod prey, generally in nearshore situations. Seabirds representing the zooplanktivore feeding guild were not infected. This indicates that pelagic foodwebs, and other trophic pathways in which Euphausia superba Dana is a dominant prey organism, are probably not involved in the life cycles of Corynosoma spp. The host and geographic distribu tions of Corynosoma in piscine, avian, and mammalian hosts suggested that oceanographic factors, particularly the Antartic Convergence, could limit the ranges for some species of parasites. Hostparasite coevolution appears to have had an important influence on the species composition of the acanthocephalan fauna of seabirds and marine mammals in Antarctica.

Helminths of Antarctic fishes: Life cycle biology, specificity and geographical distribution

“…probably have either two or three hosts. Antarctic Amphipoda are recorded as the intermediate hosts of four acanthocephalan species (Hoberg 1986, Zdzitowiecki 2001, Zdzitowiecki and Presler 2001. Zdzitowiecki (1991a) reported that acanthocephalans are common in bottom-living fishes, but absent from pelagic ones.…”

Erection of Ibirhynchus gen. nov. (Acanthocephala: Polymorphidae), Based on Molecular and Morphological Data

“…Their life cycles typically include a crustacean (amphipod, copepod, or decapod) as an intermediate host and may include fish, snakes, frogs, or toads as paratenic hosts (Schmidt, 1985;Hoberg, 1986;Nickol et al, 1999Nickol et al, , 2002. Polymorphids include approximately 127 species, classified into 11 genera (Schmidt, 1973;Dimitrova and Goergiev, 1994;Nickol et al, 1999Nickol et al, , 2002Aznar et al, 2006).…”

Changes in acanthocephalan infection of the Antarctic fish Notothenia coriiceps in Admiralty Bay, King George Island, over 29 years

“…It is possible that parallel rebuilding of parasites took place during the time and could be the reason for an increased number of cystacanths of C. arctocephali in fish (Zdzitowiecki 1987). Zdzitowiecki (1985) and Hoberg (1986) established the gentoo penguin (Pygoscelis papa) as the only final host of C. shackletoni. The abundance of the gentoo penguin population in Admiralty Bay has been fluctuating in the 29 years between the first study and the current one.…”

“…According to Palm et al (1998) N. coriiceps plays the important role in life cycles of many different parasites including Acanthocephala. The most important data on the infection of this fish with acanthocephalans were published by Johnston and Best (1937), Szidat (1965), Hoogesteger and White (1981), Hoberg (1986), Zdzitowiecki (1986aZdzitowiecki ( , 1986bZdzitowiecki ( , 2001a, Zdzitowiecki and Rokosz (1986), White (1992, 1996), Palm et al (1998), Rohde et al (1998), Zdzitowiecki et al (1998) and Zdzitowiecki and Laskowski (2004). The most extensive investigations were carried out in two localities at King George Island (South Shetland Islands): in Admiralty Bay (Zdzitowiecki 1986a(Zdzitowiecki , 1986bZdzitowiecki and Rokosz 1986) and in Potter Cove (Palm et al 1998).…”