Checklist of helminths from lizards and amphisbaenians ( Reptilia , Squamata ) of South America

A comprehensive and up to date summary of the literature on the helminth parasites of lizards and amphisbaenians from South America is herein presented. One-hundred eighteen lizard species from twelve countries were reported in the literature harboring a total of 155 helminth species, being none acanthocephalans, 15 cestodes, 20 trematodes and 111 nematodes. Of these, one record was from Chile and French Guiana, three from Colombia, three from Uruguay, eight from Bolivia, nine from Surinam, 13 from Paraguay, 12 from Venezuela, 27 from Ecuador, 17 from Argentina, 39 from Peru and 103 from Brazil. The present list provides host, geographical distribution (with the respective biome, when possible), site of infection and references from the parasites. A systematic parasite-host list is also provided.


INTRODUCTION
Parasitological studies on helminths that infect squamates (particularly lizards) in South America had recent increased in the past few years, with many new records of hosts and/or localities and description of several new species (1)(2)(3).Such studies, however, date back to 1920, when Dr. Lauro Travassos and his colleagues presented important contributions to the field of helminth systematics (4)(5)(6).
The first comprehensive efforts to summarize the knowledge about helminths of squamates are those from Baker (7), who listed all available published data on the occurrence of nematodes infecting reptiles and amphibians.Other studies have a regional scope and treat each helminth group separately, for example, nematodes collected from reptiles of Brazil, digenetic trematodes of amphibians and reptiles from Argentina and acanthocephalans in amphibians and reptiles from Brazil and Paraguay (8)(9)(10).
The present checklist summarizes the diversity of helminths from lizards and amphisbaenians of South America, providing a host-parasite list with localities and biomes.
Each record is constituted by the class, order, superfamily, family and species of the helminth; as well as the name of the authority who described it and year; besides its host(s), geographical record with country and state/province (when available) and information on biome of host.Comments include taxonomy, synonyms and also changes in the host taxonomy.
Comments: No indication of family and/or genus, but probably belong to Centrorhynchidae, since several cystacanths of this family have been found in South American lizards (16).

Kalicephalus Molin, 1861
Kalicephalus sp.Hosts: Tupinambis teguixin Site of infection: Intestine Distribution: Brazil -Sooretama, ES; Alegria (Pampas), RS.Comments: Species of Kalicephalus spp.have been reported in several snake species, and seems to be restricted to these animals, likewise Diaphanocephalus spp.(a sister taxon) in Tupinambinae.Published records could be a misidentification or a case of incidental infection in a Tupinambis teguixin (8,143,152).

FINAL REMARKS
The literature on helminth parasites of lizards and amphisbaenians from South America is extensive, dating back to the 1920's with the studies by Lauro Travassos.However, the information is scattered, and reviews of helminth parasites are necessary because they provide a basis for a better understanding on parasitism in these groups for future research (180).The need of updated knowledge becomes clear considering the valuable information that parasites provide because it is synergistic with all the information about the natural history of the hosts (181).
Helminths are high diverse in vertebrates, but the species richness are poorly known (182,183).For example, less than a half of nematode species are believed to be currently described (148).In this paper, a total of 644 records of helminths collected from lizards are reported.Since many species descriptions were made in the last decade, the diversity of helminth parasites of lizards from South America should be increased with further studies.
Of the 644 records in the present study, at least nine species of acantocephalans, 15 cestodes, 20 trematodes and 111 nematodes were reported, including records in which family or genus were not identified.From the 155 helminth species reported, one was recorded from Chile and French Guiana, three were from Colombia, three were from Uruguay, eight were from Bolivia, nine were from Surinam, 13 were from Paraguay, 12 were from Venezuela, 27 were from Ecuador, 17 were from Argentina, 39 were from Peru and 103 were from Brazil.Five species considered species inquirenda were also reported.
Lizards and amphisbaenians comprises approximately 420 genera and more than 3,300 species, most of which can be found in South America (184,185).Many South American countries exhibit great lizard diversity, for example Argentina presents 167 species while Brazil has 240 species, but data presented herein includes only 114 lizard species, which indicates that much work has to be done (186,187).
Rego & Ibañez, 1965 Hosts: Dicrodon heterolepis; D. guttulatum Duméril & Bibron, 1893 Site of infection: Small intestine Distribution: Peru -Trujillo, LL; TU, PI.Comments: Bursey and Goldberg (163) and Arizmendi-Espinosa et al. (164) apparently ignored the presence of O. freitasi in their findings of Oochoristica spp.infecting lizards in neotropical regions.The species is not included in any synonymy of the revisions made by Bursey et al.
Comments: Despite the citation by Pérez et al.
(147)record must be discharged, because no mention of Micropleura was found in Travassos and Freitas(147)as cited by Vicente et al.