Herpetology Notes, volume 11: 901-905 (2018) (published online on 01 November 2018) Oochoristica infection in anurans (Sclerophrys maculata and Ptychadena oxyrhynchus) from southern Nigeria Martins S.O. Aisien1,* and Joseph E. Igetei1 Oochoristica species are cosmopolitan anoplocephalid The anuran hosts investigated were collected from cestodes whose adults are parasitic mainly in reptilian Okomu Rubber Plantation (6°21ˊN and 6°39ˊN; 5°11ˊE hosts but occasionally in mammals (see McAllister and 5°18ˊE) located at Okomu-Udo in Ovia South-West and Bursey, 2017; Okafor, 1988). Species reported Local Government Area (LGA) of Edo State, Nigeria from Africa (O. beveridgei Masova, Tenora, Barus from June, 2010 to May, 2011and from Uzere (5°19ˊN; and Koubek 2010; O. crassiceps Baylis 1920 (Syn. 6°15ˊE) in Isoko South LGA of Delta State, Nigeria O. sigmoides Moghe 1926, O. fusca Meggit 1927); between January and May, 2017. Okomu Rubber O. jonnesi Bursey, McAllister and Freed 2011; O. Plantation is located in a rainforest biotope where the koubeki Mašová, Tenora and Baruš 2012; O. theileri wet season is from April to October and the dry season Fuhrmann 1924; O. truncata (Krabbe 1897) Zschokke lasts from November to March. Uzere is located in the 1905 (Syn. Taenia truncata Krabbe 1897); O. agamae freshwater swamp of the Niger Delta. The wet season Baylis 1919; O. africana (Malan 1939) and O. ubelakeri in this area lasts from February to October and the dry (Bursey, McAllister, Freed and Freed 1994) have all season from November to January with intermittent been described from reptilian hosts, mostly lizards. rains in the month of December. Oochoristica agamae, which infects agamid lizards has The amphibians were collected at night using the been reported from two insectivorous bats, Tadarida Visual Acoustic Encounter Survey method (Crump chaeraphon nigeriae and Hipposidero capher tephrus and Scott, 1994). In the laboratory, the anurans were (Okafor, 1988). identified (Roedel, 2000), euthanized with Benzocaine Reports on Oochoristica spp. infection among solution and post mortem examination conducted on amphibians are uncommon. The only known case is in the gastro-intestinal tract (oesophagus, stomach, small the report of Southwell and Lake (1939) who recorded intestine, large intestine and rectum), lungs, urinary O. truncata in the eastern groove-crowned bull frog, bladder, liver/gall bladder and the body cavity. Cestodes Hoplobatrachus occipitalis. In recent investigations of recovered were flattened under cover slip pressure and the parasitic helminths of anurans in southern Nigeria, fixed with 5% formol-saline. The worms were washed we recorded infections with Oochoristica species in free of the fixative and stained with acetocarmine, two anuran hosts, namely, Sclerophrys maculata and dehydrated and permanent mounts made in Canada Ptychadena oxyrhynchus. The materials obtained are balsam. Cestodes were identified using the protocols described and compared with other species from the of Beveridge (1994). Photomicrographs of the parasites Afrotropical realm. The possible role of these anurans were taken with a digital camera attached to a binocular as paratenic or transport hosts is discussed. research microscope. The amphibians collected from Okomu Rubber Plantation are listed in Table 1. Infection with Oochoristica was recorded only in S. maculata with a prevalence of 1.04%. Of the two parasite specimens found, only one had mature proglottids but it lacked gravid segments; the second specimen was immature, 1 Laboratory of Parasitology Research, Department of Animal and Environmental Biology, Faculty of Life Sciences, showing only primordia of the reproductive organs. University of Benin, P.M.B. 1154, Benin City, Nigeria. Measurements of the morphological features of the * Corresponding author. E-mail: [email protected] two worms (in µm) are shown in Table 2. The worms 902 Martins S.O. Aisien & Joseph E. Igetei Table 1. Amphibian species investigated for Oochoristica sp. at two locations inNigeria. Table 1. Amphibian species investigated for Oochoristica sp. at two locations inNigeria Amphibian species No examined at No examined at Okomu Rubber Uzere swamps Plantation Pipidae Silurana tropicalis 02 -- Bufonidae Sclerophrys maculata 96 02 Hemisotidae Hemisus mamoratus 22 -- Ranidae Hylarana galamensis -- 02 Hoplobatrachidae Hoplobatrachus occipitalis 20 01 Phrynobatrachidae Phrynobatrachus natalensis 02 -- Phrynobatrachus sp. -- 03 Arthroleptidae Arthroleptis poecilonatus 25 -- Arthroleptis sp. 08 -- Hyperolidae Afrixalus dorsalis 53 01 Afrixalus fulvovittatus -- 28 Hyperolius concolor 04 01 Hyperolius fusciventris 02 -- Hyperolius guttulatus -- 01 Hyperolius picturatus 04 -- Leptopelis spiritusnoctis 10 -- Ptychadenidae Ptychadena bibroni 45 02 Ptychadena longirostris 27 -- Ptychadena mascareniensis 39 03 Ptychadena oxyrhynchus 19 15 Ptychadena pumilio 34 02 Total 412 61 were small-sized, measuring 9170 and 5261 µm in total in shape, occurring in two clusters, with a mean number length, respectively. The scoleces measured 648 µm of 19.6±1.5 but ranged from 18-22. Among the anurans and 698 µm, respectively, in length, bearing four oval investigated at Uzere (Table 1), only Ptychadena suckers (Fig. 1A). The mature worm had 50 proglottids oxyrhynchus harboured infection with Oochoristica with the first mature segment being the 37th. Mature with a prevalence of 13.3%. The two worms recovered proglottids (Fig. 1B) had a mean length of 305 (268- were mature but differed in their sizes, measuring 10023 335) µm and were 583 (549-603) µm in breadth. The µm and 6094 µm in length, respectively (Table 2). The genital pores alternate irregularly. The testes were oval longer worm had 34 proglottids while the shorter of the Oochoristica infection in anurans from southern Nigeria 903 TableTable 2. 2. Measurements Measurements (µm) (µm) of morphological of morphological structures structures of Oochoristica of Oochoristica recovered recovered from anuran from hosts anuran hosts from Nigeria. from Nigeria Hosts Structures S. maculata . Pty. oxyrynchus Specimen 1 Specimen 2 Specimen 1 Specimen 2 Body length 9170 5261 10023 6094 Scolex length 648 671 846 939 Scolex diameter 631 698 805 778 Sucker length (mean) 210 (203-216) 225 (214-228) 236 (228-242) 261 (255-268) Sucker diameter (mean) 172 (162-189) 191 (188-201) 185 (175-188) 232 (228-242) Neck (length) 1261 1208 1274 1207 No of proglottids 50 29 34 31 First mature proglottids 37th -- 21 25 Mature proglottids (length) 305 (268-335) -- 335 (268-403) 254 (201-268) Mature proglottids (width) 583 (549-603) -- 579 (537-617) 673 (510-738) Genital atrium 37 (34-40) -- 37.6 (36-39) 26.8±0.0 Cirrus sac 60 (54-67) -- 64 (62-67) 65 (60-67) No of testes 19.6±1.5 (18-22) indistinct 14.7±1.6 (12-16) 16.3±3.1 (12-20) No of clusters 2 -- 2 2 Testes shape Oval -- Oval Oval Testes length 62.4±7.2 -- 76.5±9.1 45.6±6.9 Ovary (total width) 379.6±29.7 -- 389.2±25.6 281.8±28.5 Ovary (lobule no) 11-19 -- 8-14 8-14 Vitellaria 128.2±117.9 -- 132.0±15.0 120.8±19.0 Gravid proglottid None None None None two had 31. The scolex (Fig. 1C) bore four oval suckers 2016, 2017a; Imasuen et al., 2012), while C. compactus and the mature proglottid of the parasite is shown in occurs in pipid anurans (Xenopus muelleri and Xenopus Figure 1D. The testes were oval and occurred in two (Silurana) tropicalis and Hoplobatrachus occipitalis clusters, ranging from 12 to 20 in number. No gravid (Jackson and Tinsley, 2001; Aisien et al., 2017a). segments were observed in these specimens. Larval proteocephalids, whether encysted or free in the From published information on the helminths intestine, use different anuran species as paratenic hosts parasitizing amphibians in Nigeria, four cestode species (Imasuen et al., 2012; Aisien et al., 2017a). Cysticercoids are known to occur in these hosts and they include of Diplopylidium triseriale, a parasite of viveriids Cylindrotaenia jaegerskioeldi, Cephalochlamys similarly uses Sclerophrys maculata, Phrynobatrachus compactus, larval proteocephalids (Aisien et al., calcaratus and Ptychadena mascareniensis as paratenic 2001, 2009, 2015, 2017a) and larvae of Diplopylidium hosts (Aisien et al., 2017a). triseriale (Aisien et al., 2017b). Cylindrotaenia Oochoristica sp. recorded in S. maculata and Pty. jaegerskioeldi and C. compactus occur as adults while oxyrhynchus in this study represents the fifth cestode juveniles and encysted larvae of proteocephalids have infection in Nigerian amphibians. It however represents been recorded in Nigerian anurans (Aisien et al., 2009, the second record of Oochoristica sp. in an anuran 2016, 2017a); the cysticercoids of D. triseriale occur host in Africa. Southwell and Lake (1939) recorded either on the liver or on the intestinal mesentery of Oochoristica truncata (Syn. Taenia truncata Krabbe the infected anurans. Cylindrotaenia jagerskioeldi and 1879; Oochoristica agamae Baylis 1919; Oochoristica Cephalochlamys compactus are generalist parasites, africana Malan 1939; Oochoristica africana var with C. jaegerskioeldi infecting both terrestrial and ookispensis Malan 1939) in Hoplobatrachus occipitalis arboreal frogs (Aisien et al., 2001, 2003, 2004, 2009, collected in Belgian Congo. All other reports of 904 Martins S.O. Aisien & Joseph E. Igetei size range. Secondly, the mature proglottids in both specimens were wider than long, which is in direct contrast to those of other Oochoristica spp., where the proglottids were longer than wide (see McAllister and Bursey, 2017). Thirdly, the testes in both materials occurred in two clusters and the follicles are oval in shape. It is also obvious that the present parasite is not O. truncata recovered from H. occipitalis by Southwell and Lake (1939). Apart from their size differences, the present parasite has a neck which is lacking in O. truncata. Whereas the sucker in O. truncata is circular, those in the present materials are oval. There are also differences in the number and arrangement of the testes in the two parasites. While the number of testes in O. truncata range from 27 to 48 and arranged in one cluster, those in the present specimens from these anurans are less than 30 and are arranged in two clusters.