Anurans from the rainforest (Okomu National Park) and derived savanna (Agbede) locations in Nigeria were investigated for their role either as intermediate or paratenic hosts of helminth infections. A total of 269 anuran specimens (157 from the Okomu National Park and 112 from Agbede) were examined. Metacercariae of a strigeoid trematode, two nematode species, a proteocephalid cestode, and an acanthocephalan were recovered from infected hosts. Except for the strigeoid trematode, which was only recorded in the rainforest, there was no ecological dichotomy in the distribution of the larval parasites recorded. Tree frogs from the rainforest only served as second intermediate hosts for the strigeoid trematode. The two nematode larvae (type I and type II) found in the body cavity of the infected host are believed to use them as paratenic hosts. Tree frogs were the predominant intermediate hosts of the proteocephalid cestode larvae in the rainforest, while Ptychadena and Phrynobatrachus spp. served this function in the derived savanna. The occurrence of cystacanths in the anurans from both biotopes confirms their known role as paratenic host for acanthocephalans. Afrixalus dorsalis is a new host record for the ascaridoid nematode while the finding of the strigeoid trematode, the proteocephalid cestode larvae and acanthocephalan cystacanths in the anurans investigated represents new geographical records.

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The parasitic infections of market derived Osteolaemus tetraspis from the rainforest and Varanus ornatus from locations in the savanna-mosaic and the rainforest of southern Nigeria were investigated. Parasites recovered from O. tetraspis included members of the Pentastomida, Trematoda and Nematoda. An undescribed pentastomid belonging to the family Sebekidae was recovered from O. tetraspis. The same parasite was also found to parasitize V. ornatus from the rainforest. Other parasites found in O. tetraspis were Pseudoneodiplostomum thomasi, Dujardinascaris sp. and larva of a Camallanus sp. Varanus ornatus from the rainforest and the derived savanna had some parasites including Duthiersia fimbriata, an unidentified pseudophyllidean cestode and Tanqua tiara in common. Cosmocerca ornata and Oswaldocruzia hoepplii were restricted to hosts from the derived savanna while the unidentified trematode occurred only in lizards from the rainforest. The unidentified pseudophyllidean cestode bears a close resemblance to Probothriocephalus, a cestode previously reported only from deep water teleosts. Pseudoneodiplostomum thomasi and Duthiersia fimbriata are new locality records for Nigeria.

An investigation of the digenetic trematodes of anurans from Agbede, a location in the derived savanna biotope in Edo state,Nigeria was conducted from August, 2007 to July, 2008. Anuran hosts examined included Sclerophrys maculata, S.regularis, Ptychadena pumilio, P. bibroni, P. oxyrhynchus, Hoplobatrachus occipitalis and Hylarana galamensis. Theanurans were collected using the Visual Acoustic Encounter Survey (VAES) method, dissected and examined for trematodeinfections. A total of 267 anurans were examined of which 33 were infected with an overall prevalence of 12.36%. Seasonalprevalence was 14.88% for the wet season and 8.08% for dry season. The difference in prevalence values was not statisticallysignificant (p >0.05). Four digenetic trematodes, namely, Mesocoelium monodi, an unidentified Mesocoelium sp.,Haematoloechus exoterorchis and an unidentified Haematoloechus sp. Haematoloechus exoterorchis was recovered from H.occipitalis while the unidentified Haematoloechus sp. infected H. occipitalis and Sclerophrys maculata. Mesocoeliummonodi infected only Sclerophrys maculata while the unidentified Mesocoelium sp. was a generalist, infecting five anuranhosts. Sclerophrys maculata is thus a new host record for the genus Haematoloechus in Nigeria. In conclusion, this studyrevealed a low trematode diversity in the anurans of the savanna-mosaic at Agbede. However, anurans from this locationharboured two new trematodes: an unidentified Mesocoelium sp and a Haematolechus sp. Sclerophrys maculata as a newhost record for the genus Haematoloechus in Nigeria. More specimens of the Haematoloechus sp. are needed for themorphological description and molecular characterization of the parasite, to establish its relationship with the cogener inH.occipitalis. Keywords: Derived savannah, Anurans, Digenetic trematodes, new host record

As part of a broader study to increase the information of parasite infections of anurans from the savanna biotope, an investigation of the nematode parasites of anurans in Agbede, a location in the derived savanna of Edo State, Nigeria was undertaken from August 2007 to July 2008. Anurans were collected at night using the visual acoustic encounter survey (VAES) sampling method, dissected and examined for nematode infections. A total of 329 anurans belonging to sixteen taxa, were examined, of which 235 were infected with an overall prevalence of 71.43%. Seasonal prevalences were 85.63% for wet season and 52.48% for the dry season (p<0.05). Ten nematode species, namely: Amplicaecum africanum, Cosmocerca ornata, Oswaldocruzia hoeplii, Physaloptera sp., Rhabdias africanus, Rhabdias sp., Camallanus dimitrovi, an unidentified oxyurid nematode, Ophidascaris larva, and an unidentified nematode were recovered from the hosts examined. The most common nematode species was Amplicaecum africanum (31.31%), whereas the least common was an unidentified oxyurid nematode (0.30%).Physaloptera sp. is a new record for the anurans of the derived savanna.