Checklist of Platyhelminthes , Acanthocephala , Nematoda and Arthropoda parasitizing penguins of the world

Host–Parasite Database, a partial implementation of which is now available on-line (Gibson et al. 2005). Secondly, searches of the Zoological Record, Biological Abstracts and Helminthological Abstracts, Web of Knowledge, Google Scholar and the Scopus databases were undertaken up to October, 2013. The checklist follows the parasite classification and systematic arrangement of Gibson et al. (2002) and Jones et al. (2005) for Digenea; Khalil et al. (1994) for Cestoda; Anderson et al. (2009) for Nematoda; Amin (2013) for Acanthocephala; Gugliemone et al. (2010) for Acari; and Clay (1967) for Insecta with some modifications based on recent records. The species of parasites are presented in alphabetical order, followed by hosts with its respective site of infection and localities, and the references in chronological order. We adopted the 18 recognized species by Birdlife International and International Union for Conservation of Nature (IUCN), the global organization which is the sponsor of the Red List of Threatened Species (Birdlife International 2013; IUCN 2010). The parasite species names have been updated to agree with the recent literature, but inclusion in the parasite or host lists does not imply that the authors necessarily agree with their validity. This compilation is presented as parasite-host and hostparasite lists. We have attempted to include information from all published reports.


Introduction
Penguins are seabird animals that live only in the Southern Hemisphere.They breed in climates that range from -60°C to +40°C, breeding farther south than any other birds, up to the latitude of 77°33′ S. They also breed right on the Equator in the Galápagos Island.Penguins can be found around South America, southern Africa, Australia, New Zealand, and the islands of the subantarctic (Davis 2007).
There are six clearly defined genera of extant penguins: Aptenodytes, Eudyptes, Eudyptula, Megadyptes, Pygoscelis and Spheniscus, all from the same family Spheniscidae.WoRMS (2013) recognized 18 valid species of penguins.Some species are reconized by some authors as valid but others as subspecies only (Marchant and Higgns 1990;Sibley et al. 1990;del Hoyo et al. 1992).
The wild penguins are commonly parasitized by ectoparasites such as fleas (Siphonaptera), lice (Phthiraptera), mites and ticks (Acari) (Murray et al. 1991;Clarke and Kerry 1993), which may act as vectors of many diseases.Several endoparasites such as trematodes, cestodes, acanthocephalans, nematodes and coccidian can also be found on these organisms (Clarke and Kerry 1993;Duignan 2001;Barbosa and Palacios 2009), causing damages more or less serious to the host health.Information regarding to parasites and their associated hosts may be useful to studies on biodiversity, biogeography and also on host phylogeny.Here we provide a checklist of the metazoan parasites reported from penguins including the information on parasite distrution and site of infection.The information is presented as parasite-host and host-parasite lists.

Discussion
Endoparasites were the richest group presenting highest richness of species with 68 species of parasites, while ectoparasites were represented by 40 species.The transmission of this group of parasites tends to be favored by the feeding of the penguins, which consists mainly of fishes, squids and krill, the former being one of the main intermediate hosts for these parasites.
Spheniscus magellanicus (20), Eudyptula minor (16) and Pygoscelis papua (14) present the richest helminth communities.These results may be influenced by the distribution of the species and by the effort of the researchers on the knowledge of the parasitic fauna of this species and its health state, seeing that some of then can cause serious damages to the host.
The poorest parasite richness is found in E. moseleyi and S. mendiculus.Eudyptes moseleyi has a restricted breeding range (Davis and Renner 2003), occurring just on seven islands with a total land area of 250 km 2 , and the low number of parasitological studies in this species certainly plays an important role.
The phylogeny is an important factor that shows the relationship among penguins' species and helminths (Poulin and Morand 2004).It is more frequent to find the same species of helminths among penguins of the same genus.Notwithstanding all penguins came from the same family and also share some helminth species.Parasites are useful in information on host ecology, biogeography and phylogeny (Raga et al. 2008;Gardner and Campbell 1992), and also serve as indicators of current and historical ecological relationships (Aznar et al. 2001).
Recently Brandão et al. (2013) added 60% of the Magellanic penguin's parasite fauna known so far, and this is a well studied species of penguin.Thus indicating the necessity of the maintenance of information on the biodiversity of parasites of penguins, mainly at remote places like Antarctica.