Prey Composition of Two Syntopic Phrynobatrachus Species in the Swamp Forest of Banco National Park, Ivory Coast

Prey composition of two syntopic Phrynobatrachus species

SALAMANDRA 44 3 177-186 Rheinbach, 20 August 2008 ISSN 0036-3375

Prey composition of two syntopic Phrynobatrachus species in the swamp forest of Banco National Park, Ivory Coast

N’Goran Germain Kouamé, Blayda Tohé, N’Guessan Emmanuel Assemian, Germain Gourène & Mark-Oliver Rödel

Abstract. We studied the diet of two syntopic and morphologically very similar leaf litter frogs, Phryno- batrachus ghanensis and P. phyllophilus, in Banco National Park, south-eastern Ivory Coast. We determined the prey composition of females of both species to understand the potential avoidance of competition for food. Insects dominated (> 80%) the general diet of both species. We determined insect prey items down to the level of the order. At this level the diet of both species differed, however not significantly. Whereas P. ghanensis preyed mainly on hymenoptera (65.6%, mostly ants); P. phyllophilus mainly preyed on coleoptera (56.8%). With respect to seasons these differences were even larger, although again not statistically significant. Hence, there seem to be some differences in the food preference of the two species. However, the large overlap in prey can be taken as a hint that competition for food does not play a major role between these two frogs. The slightly different diets are more likely the result of so far undetected differences in habitat preferences and / or activity patterns. Key words. Amphibia: Anura: Phrynobatrachidae: Phrynobatrachus ghanensis, P. phyllophilus, diet, swamp forest, syntopic occurrence, West Africa.

Résumé. Les régimes alimentaires de Phrynobatrachus ghanensis et P. phyllophilus, deux grenouilles de litière vivant en sympatrie et morphologiquement très proches ont été étudiés dans le Parc National du Banco, sud-est de la Côte d’Ivoire. Chez des individus femelles, les types de proies ont été déterminées afin de comprendre comment les deux espèces peuvent-elles éviter les effets de nuisance relatifs à la com- pétition pour la nourriture dans un même habitat. Les insectes dominent le régime alimentaire général de P. ghanensis et de P. phyllophilus (> 80%). Pour ce qui concerne les ordres des proies consommées, les deux espèces diffèrent. P. ghanensis se nourrit principalement d’hyménoptères (65,5%), en particulier de fourmis. En revanche, P. phyllophilus consomme principalement les coléoptères (56,8%). Cette diffé- rence observée entre espèces n’est cependant pas significative du point de vue statistique. Concernant les régimes saisonniers, les variations enregistrées au niveau des préférences alimentaires sont grandes, mais non significatives sur le plan statistique. Certes, il semble y avoir des préférences alimentaires chez ces deux espèces. Mais, un grand chevauchement trophique pourrait insinuer que la compétition pour la nourriture ne joue pas un rôle majeur entre les deux espèces de grenouilles. Les légères différences des régimes alimentaires sont plus vraisemblablement, de loin, le résultat de l’existence d’habitat et/ou d’activités non décelés. Mots-clés. Amphibia: Anura: Phrynobatrachidae: Phrynobatrachus ghanensis, P. phyllophilus, régime alimentaire, forêt marécageuse, occurrence en sympatrie, Afrique de l’Ouest.

Introduction tats, ranging from dry savanna to rainforests (Rödel 2000, Channing 200, Chan- The genusPhrynobatrachus is one of the most ning & Howell 2006). With a few excep- species rich African anuran genera (Poyn- tions (Rödel & Ernst 2002a, b, Rödel et al. ton 999). Currently approximate 72 valid 2004), Phrynobatrachus species exhibit simi- species are known, occurring exclusively in lar reproduction strategies and often occur in Sub-Saharan Africa (Frost 2007). Species sympatry (Lamotte & Dzieduszycka 958, of this genus inhabit a huge variety of habi- Barbault & Trefaut Rodrigues 978, 979,

Barbault & Pilorge 980, Barbault 984, was only recently rediscovered (Rödel et al. Rödel 998, 2000, De Sá & Channing 2003, 2005). In Banco National Park, this species Ernst et al. 2006). From West African forests seems to reach its westernmost distribution up to 3 Phrynobatrachus species have been limit (Assemian et al. 2006). Phrynobatra- reported (Rödel & Ernst 2004). Although, chus phyllophilus Rödel & Ernst, 2002 was some Phrynobatrachus species, together described from western Ivory Coast and has with members of the genus Arthroleptis, are its easternmost distribution limit in Ban- among the most abundant leaf litter frogs in co (Assemian et al. 2006). Both species are West Africa, there seem to be no or only mi- small leaf litter frogs of similar morphology nor competition for food between these spe- and size that prefer swampy parts of primary cies (Ernst & Rödel 2006). However, only a rainforests. The Banco National Park is the few studies have so far investigated the prey only site where both species are known to oc- of Phrynobatrachus species (Inger & Marx cur in sympatry and even syntopy. 96, Barbault 974a, Rödel 995). In Ban- co National Park two morphologically very similar and abundant Phrynobatrachus spe- Prey composition cies, Phrynobatrachus ghanensis and P. phyllophilus, co-occur in the swampy parts of the Within a general amphibian monitoring pro- primary forest (Assemian et al. 2006, N.G. gram of the National Park (see Assemian et Kouamé unpubl. data). In this paper we in- al. 2006) we searched for frogs along vari- vestigate what these two species prey upon ous transects. A transect was 600 m in length and if their food composition is diﬀerent or and 2 m width (surface searched for frogs per not. transect walk: ,200 m²). Each transect was walked for 24 times; every transect walk last- ed app. 45 min. A detailed description of the Materials and methods collecting method and the general transect Study site design is given by Rödel & Ernst (2004). Between March 2004 and February 2005 we The Banco National Park (BNP, 5°2’-5°25’ N; collected 30 adult females of both species, on 4°0’-4°05’ W) is a small (3000 ha) rain for- two transects (BT5 and BT6; compare As- est park, located in the middle of Abidjan, the semian et al. 2006) in swampy parts of the economic capital of Ivory Coast. The mean rainforest (see Appendix). We collected 4 P. annual temperature in Banco is 26-27°C. ghanensis during the rainy season and 6 dur- The mean annual precipitation ranges from ing the dry season. From P. phyllophilus we 600-2500 mm. A longer major dry season collected 8 specimens during the rainy and extends from December to March, and is fol- 2 specimens during the dry season. Snout- lowed by the period with highest precipita- vent-lengths of the living frogs were taken tion in March to July. A minor rainy season with dial callipers (accuracy ± 0.5 mm). Un- lasts from October to November. Assemian fortunately the frogs were too small and too et al. (2006) provide an overview about the fragile to employ stomach-ﬂushing, as e.g. de- climate, vegetation and especially the anuran scribed by Joly (987) and Solé et al. (2005). fauna of this park. Hence, frogs were euthanized in a chlorob- utanol solution and thereafter dissected. Stomachs were preserved in 70% ethanol and Target species stomach content analyzed in the laboratory with the aid of a dissecting microscope. For Phrynobatrachus ghanensis Schiøtz, 964 every specimen we determined and count- was described from rainforests in southern ed the prey items, and thereafter dried and Ghana (Schiøtz 964, Perret 988) and weighed the prey (Sartørius scale; accuracy

178 Prey composition of two syntopic Phrynobatrachus species

± 0.000g). We distinguished between insect were classified according to the scheme of orders, arachnids (Arachnida), crustaceans Simenstad (970). As principal prey we de- (Isopoda), myriapods (Diplopoda), and oth- fined those prey items that summed to more er animal remains and plant parts (Dierl & than 50% of the Ip index. As secondary prey Ring 992, Tachet et al. 2003). As the frogs we defined those items that accomplished the had to be killed for the analyses we decided Ip index to more than 75%. We used the in- to restrict the study to females. The speci- dex of shared prey Cλ according to Morisita mens hence could be additionally used for (959) modified according to Horn (966) research questions that concern the repro- to evaluate the prey overlap between the two ductive effort and strategies of both species species. Cλ would be 0 is the prey composi- (N.G. Kouamé unpubl. data). The frogs are tion in both species would be completely deposited in the collection of the Laboratoire different; Cλ is  if the prey of both species d’Environnement et de Biologie Aquatique at is identical. A Cλ value larger than 0.6 rep- the University Abobo-Adjamé, Abidjan (Ap- resents a significantly different trophic niche pendix). (Zaret & Rand 97).

Statistical analysis Results

For a quantitative analysis of the frogs’ diets Snout-vent-lengths in female P. ghanensis we calculated: the percentage or the frequen- varied from 7.5-20.5 mm; SVL in P. phyllo- cy of presence F (Rosecchi & Nouaze 987, philus ranged from 4.5-2.0 mm. Hence both Gray et al. 997, Young et al. 997); the exact species showed no significant size differences percentage of prey weight P (Hyslop 980) (Mann-Whitney-U; Z = .38; p = 0.255; N = and the index of occurrence of the percent- 60). During 240 transect walks we recorded age of weight Ip [Ip = (F.P*00)/(ΣF.P); Ip 394 P. ghanensis (2.2 individuals per transect- may vary from 0 to 00, Natarajan & Jh- hour) and 303 P. phyllophilus (.7 frogs / t-h). ingran 96]). The different prey categories We recorded P. ghanensis on transects BT Tab. 1. Number of particular prey items (n) in stomachs of Phrynobatrachus ghanensis and P. phyllophilus (each N = 30).

Phrynobatrachus ghanensis Phrynobatrachus phyllophilus n stomachs n stomachs Coleoptera 6 4 0 9 Dermaptera – – 2 2 Diptera 8 7 2 2 Heteroptera – – 2 2 Hymenoptera 6 30 69 8 Isoptera 2 2 2 2 Lepidoptera 4 3 2 2 Orthoptera 3 3 3 2 Thysanoptera 2 2 2 2 Arachnida 0 9 5 4 Isopoda 3 2 0 0 Diplopoda 2 2 0 0 other animals 7 7 8 8 plants 5 5  

179 N’Goran Germain Kouamé et al.

(0 specimens), BT4 (5), BT5 (25), BT6 (242) items for both species through both seasons and BT7 (2). We found P. phyllophilus on (Tab. 2), but especially for P. ghanensis dur- BT4 (2), BT5 (238) and BT6 (63). The number ing the rainy season. During the dry season of individuals per transect was not signifi- arachnids became of increasing importance cantly different (Wilcoxon paired-test, Z = - for both species. During the dry season flies 0.944; p = 0.345; N = 5). For a short habitat became the most dominant prey item for description of the transects see Assemian et P. ghanensis and this species then also cap- al. (2006). tured more woodlice and butterflies (Tab. 2). We found prey items in the stomachs of Phrynobatrachus phyllophilus switched from all 60 frogs (Tab. ). In total we found six dif- predominant beetle prey in the rainy season ferent major prey categories consumed by P. to hymenopterans and arachnids in the dry ghanensis (Insecta, Arachnida, Isopoda, Di- season. Eleven stomachs of P. phyllophilus plopoda, other animals and plants) and four contained plant items, eight stomachs were major prey categories in P. phyllophilus stom- almost completely filled with plants parts, ac- achs (Insecta, Arachnida, other animals and counting for the high percentage of this “prey plants). In Table 2 the percentage of prey item” (Tabs. +2). However, neither in P. categories (Ip) consumed by both species is ghanensis (Mann-Whitney-U; Z = - 0.793; p summarized. Both species mainly preyed on = 0.427) nor in P. phyllophilus (Mann-Whit- insects, 8.8% and 80.5%, respectively. Co- ney-U; Z = 0.390; p = 0.696), prey compo- leoptera and Hymenoptera dominated the sition differed significantly between the two diet of both species. However, whereas P. seasons. Likewise the trophic niche of both ghanensis mainly preyed on hymenopterans species did not differ significantly, neither

(predominantly ants), P. phyllophilus seemed during the rainy (Cλ = 0.49), nor during the to prefer beetles (Tab. 2). Hymenopterans dry season (Cλ = 0.39). (predominantly ants) were important prey

Tab. 2. Percentage (Ip% Index, see Materials and methods) of prey categories consumed by female Phrynobatrachus ghanensis and P. phyllophilus throughout a whole year (complete), during the rainy (rainy) or dry (dry season, respectively (Sample size in parentheses).

Phrynobatrachus ghanensis Phrynobatrachus phyllophilus Season / complete rainy dry complete rainy dry Prey category (N = 30) (N= 4) (N= 6) (N= 30) (N= 8) (N= 2) Coleoptera 5.07 4.02 6.47 56.77 69.34 .6 Dermaptera – – – 0.04 – 0.78 Diptera 6.75 0.30 25.76 0.0 0.6 – Heteroptera – – – 0.22 – 3.88 Hymenoptera 65.55 82.8 6.98 22.6 7.62 35.40 Isoptera 0.02 0.05 – 0.8 – 3.3 Lepidoptera .5 – 0.54 0.03 – 0.48 Orthoptera 2.88 2.4 .60 0.49 – 8.73 Thysanoptera 0.0 – 0.04 0.09 0.4 – Insecta (Σ) 8.79 89.59 6.39 80.53 87.26 53.73 Arachnida 3.93 0.37 7.72 .30 0.05 .06 Isopoda .75 7.7 6.87 – – – Diplopoda 0.50 .43 – – – – other animals .5 0.66 2.66 3.00 3.0 .75 plants 0.53 0.24 .36 5.7 9.59 33.46

180 Prey composition of two syntopic Phrynobatrachus species

Discussion composition in populations of one species, living in different areas or habitats. These Whereas in some reptile assemblages compe- “preferences” are then directly dependant on tition for food seems to play a role, or spe- the availability of the respective prey species. cies differ to a high degree in specializing on For example the frog Aubria subsigillata pre- particular diets (Toft 985, Akani et al. 200, dominantly feeds on fish in Gabon (Epiplatys Luiselli 2006), it is assumed that competi- spp.) but not in Ghana (Knoepffler 976, tion for food is only of minor importance in Hughes 979). anurans that generally feed on a huge variety Phrynobatrachus spp. usually occur in of prey items (Toft 980a, b, Kuzmin 995, very high abundances in African forest Hofer et al. 2004, Ernst & Rödel 2006). For (Ernst & Rödel 2006) as well as in savan- example the herpetofauna of Lamto, a forest- na ecosystems (Barbault 967, Gardner et savanna mosaic in Central Ivory Coast, con- al. 2007). During the rainy season in Lam- sists of species with a specialised diet (snakes) to four Phrynobatrachus species accounted and species that feed on very diverse prey for 8.6% of the savanna amphibians and for items (amphibians, lizards and some snakes, 74% of the anurans in the gallery forest (Bar- Barbault 974b). Particular prey preferenc- bault 972). During the core rainy season es in lizards are often correlated with habitat these Phrynobatrachus species achieved den- and foraging mode, although this correlation sities of up to 453 individuals per hectare in seems to differ between different ecosystems a swampy valley (Barbault 972). Such den- (Huey & Pianka 98, Gasnier et al. 994). sities might result in a competition for food. Wild (994) reports competition for food be- However, the limiting factor for amphibian tween a toad, Bufo camerunensis and a rep- populations in Lamto was not food, but rain- tile, the ground dwelling chamaeleon Rham- fall (Barbault 974b). pholeon spectrum, the toad out-competing In our study both species occurred often the reptile. in sympatry, namely swampy parts in pri- So far competition for food in amphib- mary rainforests. Their microhabitat choice ians was only recorded in laboratory experi- seemed to be the same (N.G. Kouamé un- ments with unnaturally high densities (Kuz- publ. data) and the two species occurred in min 995) or tadpoles in very special natu- comparable densities. The observed densities ral habitats (Woodward 982, Osborne & were far lower than those in Lamto, hence al- McLachlan 985, Rudolf & Rödel 2005). ready contradicting the potential importance It seems that food normally cannot be con- of competition for food between the two spe- sidered a limited resource for amphibians. In cies. This was further supported by the fact Lamto the arthropods, mostly consumed by that the differences in food composition be- the various anuran species, were extremely tween the two species were not significant. abundant (Barbault 974a). With a few ex- In our study all stomachs were filled. Thus ceptions adult anurans are known to be ex- it seems that both species frequently feed clusively carnivorous (but see below) and to all year round. Although it is believed that especially feed on a variety of small arthro- frogs do not normally feed on plants, it is pods (Kam et al. 998, Hirai & Matsui 999; known that some frogs may have consider- but e.g. only termites and ants in Hemisus able amounts of plant material in their stom- marmoratus, Barbault 974a, Rödel et al. achs. Simon (983) found more plant mate- 995), and hence are generally regarded as rial in breeding than in non-breeding indi- opportunistic feeders (e.g. Inger & Marx viduals of a New Guinean microhylid frog. 96, Barbault 974a, Duellman & Trueb We detected more plants during the dry sea- 986). This is reflected in seasonal shifts in son than during the rainy season. Hence, we food composition (Inger & Marx 96, Toft would not a priori exclude the possibility that 980a, b) or by profound differences of prey some plants are devoured deliberately dur-

181 N’Goran Germain Kouamé et al. ing less favourable periods and were not only tles as dominant food may hence reflect some swallowed randomly. This possibility is fur- so far undetected differences in the frogs’ mi- ther supported by the fact that the high per- cro-habitat choice and / or activity patterns, centage of plant material in the dry season rather than being the result of current com- diet of P. phyllophilus was due to some stom- petition for food. Further in-detail-analyses achs completely filled with plants (for frogs of the habitat requirements and the species’ that deliberately feed on plants compare Da behaviour may help clarifying this point. Silva & De Britto-Pereira 2006 and other literature cited therein). The Phrynobatra- chus species’ ability to digest plant matter is Acknowledgements completely unknown. We are especially grateful to the “Office Ivoirienne However, and as expected, insects in gen- des Parcs et Réserves” and the “Direction des Eaux eral and beetles and ants in particular were et Forêts de Côte d’Ivoire” for the access permit to dominant in the prey of both frog species in- Banco National Park. The research permission was vestigated. The dominance of ants and bee- issued by the “Ministère de l’Enseignement Su- tles in the diet was also revealed in six Con- périeur et de la Recherche Scientifique”, Republic golese Phrynobatrachus species by Inger & of Côte d’Ivoire. This paper is part of the projects Marx (96). They partly observed differen- “Banco-Santé-Ecologique” at the “Laboratoire ces in diets between the sexes, altitudes and d’Environnement et de Biologie Aquatique” of the University Abobo-Adjamé, Abidjan and the BIO- seasons. P. anotis ate more beetles during LOG-program of the German Ministry of Educa- the dry, more ants in the wet season. In con- tion and Science (BMB+F; Project W08 BIOTA- trast P. perpalmatus consumed beetles, cica- West, FZ 0 LC 0040). Timo Moritz commented das and spiders in the wet season and beetles, on a previous draft of the manuscript. These sup- cicadas and flies in the dry season. Phryno- ports are gratefully acknowledged! batrachus rungwensis (termed P. gutturosus is this publication) and P. natalensis preyed much on termites, but only during the wet References season. Only in P. perpalmatus ants did not play an important role, which might be ex- Akani, G.C., O.K. Ogbalu & L. Luiselli (200): plained by the aquatic habitat of the frog, Life-history and ecological distribution of cha- from which the ants were nearly absent. In meleons (Reptilia, Chamaeleonidae) from the the other five Phrynobatrachus species In- rain forest of Nigeria: conservation implicati- ger & Marx (96) explained the dominance ons. – Animal Biodiversity and Conservation, of ants in the prey samples with the overall 24: -5. dominance of these insects. A similar pref- Assemian, N.E., N.G. Kouamé, B. Tohé, G. erence for beetles like in P. perpalmatus, and Gourène & M.-O. Rödel (2006): The anur- the scarcity of ants was recorded from the ans of the Banco National Park, Côte d’Ivoire, prey of the semi-aquatic P. accraensis at the a threatened West African rainforest. – Sala- mandra, 42: 4-5. end of the dry season (Rödel 995, termed P. francisci in this paper). We observed simi- Barbault, R. (967): Recherches écologiques dans la savane de Lamto (Côte d’Ivoire): Le cycle lar, although not significant seasonal switch- annuel de la biomasse des amphibiens et des es in food composition like Inger & Marx lézards. – Terre Vie, 3: 297-38. (96). Even though we have not simultane- Barbault, R. (972): Les peuplements d’amphibiens ously recorded the availability of the respec- des savanes de Lamto (Côte d’Ivoire). – Anna- tive prey, we presume that the food choice in les de l’Université d’Abidjan, Sér E., 5: 59-42. the two Phrynobatrachus species most likely Barbault, R. (974a): Le régime alimentaire can be explained by differences in the avail- des amphibiens de la savane de Lamto (Côte ability of the various arthropod taxa. The dif- d’Ivoire). – Bulletin de l’Institut fondamental ferences in the consumption of ants and bee- d’Afrique noire, Sér A, 36: 952-972.

182 Prey composition of two syntopic Phrynobatrachus species

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Appendix

Field numbers, size and origin of Phrynobatrachus females examined in this work. Vouchers will be all deposited in the collection of the Laboratoire d’Environnement et de Biologie Aquatique at the University Abobo-Adjamé, Abidjan. BT = Banco transect; SVL = Snout-Vent-Length.

Species Specimens SVL (mm) Transects Date of capture P. ghanensis No. 20.0 BT6 0.03.2004 P. ghanensis No.2 8.5 BT6 07.04.2004 P. ghanensis No.3 7.5 BT6 07.04.2004 P. ghanensis No.4 8.0 BT6 8.05.2004 P. ghanensis No.5 20.5 BT6 8.05.2004 P. ghanensis No.6 9.0 BT6 8.05.2004 P. ghanensis No.7 20.0 BT5 02.06.2004 P. ghanensis No.8 9.0 BT5 02.06.2004 P. ghanensis No.9 8.0 BT5 29.06.2004 P. ghanensis No.0 20.0 BT6 29.06.2004 P. ghanensis No. 9.0 BT5 30.06.2004 P. ghanensis No.2 9.0 BT5 30.06.2004 P. ghanensis No.3 20.0 BT5 07.07.2004 P. ghanensis No.4 8.0 BT5 08.07.2004 P. ghanensis No.5 8.0 BT5 08.07.2004 P. ghanensis No.6 8.0 BT6 05.08.2004 P. ghanensis No.7 20.0 BT6 0.09.2004 P. ghanensis No.8 9.5 BT6 0.09.2004 P. ghanensis No.9 7.5 BT5 6.09.2004 P. ghanensis No.20 9.5 BT5 6.09.2004 P. ghanensis No.2 8.5 BT5 6.09.2004 P. ghanensis No.22 8.0 BT5 28.2.2004 P. ghanensis No.23 7.5 BT5 28.2.2004

185 N’Goran Germain Kouamé et al.

Species Specimens SVL (mm) Transects Date of capture P. ghanensis No.24 8.5 BT6 28.2.2004 P. ghanensis No.25 8.5 BT6 28.2.2004 P. ghanensis No.26 8.5 BT6 25.0.2005 P. ghanensis No.27 9.0 BT6 25.0.2005 P. ghanensis No.28 9.0 BT6 25.02.2005 P. ghanensis No.29 20.0 BT6 25.02.2005 P. ghanensis No.30 8.0 BT6 25.02.2005 P. phyllophilus No.3 20.0 BT5 06.04.2004 P. phyllophilus No.32 9.0 BT5 06.04.2004 P. phyllophilus No.33 9.0 BT6 06.04.2004 P. phyllophilus No.34 9.0 BT6 06.04.2004 P. phyllophilus No.35 9.0 BT5 07.04.2004 P. phyllophilus No.36 8.5 BT5 07.04.2004 P. phyllophilus No.37 8.0 BT6 07.04.2004 P. phyllophilus No.38 9.0 BT5 8.05.2004 P. phyllophilus No.39 20.0 BT5 02.06.2004 P. phyllophilus No.40 2.0 BT5 02.06.2004 P. phyllophilus No.4 20.0 BT5 02.06.2004 P. phyllophilus No.42 20.0 BT5 02.06.2004 P. phyllophilus No.43 20.0 BT5 03.06.2004 P. phyllophilus No.44 7.0 BT6 29.06.2004 P. phyllophilus No.45 8.0 BT6 08.07.2004 P. phyllophilus No.46 20.0 BT6 08.07.2004 P. phyllophilus No.47 9.0 BT5 05.08.2004 P. phyllophilus No.48 8.0 BT5 05.08.2004 P. phyllophilus No.49 8.0 BT6 05.08.2004 P. phyllophilus No.50 9.5 BT5 0.09.2004 P. phyllophilus No.5 8.0 BT5 0.09.2004 P. phyllophilus No.52 8.5 BT5 0.09.2004 P. phyllophilus No.53 4.5 BT5 0.09.2004 P. phyllophilus No.54 20.0 BT6 6.09.2004 P. phyllophilus No.55 9.5 BT5 8.0.2004 P. phyllophilus No.56 20.0 BT6 22..2004 P. phyllophilus No.57 8.5 BT5 28.2.2004 P. phyllophilus No.58 20.0 BT5 28.2.2004 P. phyllophilus No.59 8.5 BT5 25.0.2005 P. phyllophilus No.60 8.5 BT5 25.0.2005

Manuscript received: 3 May 2007 Authors’ addresses: N’goran Germain Kouamé, Blayda Tohé, N’Guessan Emmanuel Assemian, Germain Gourène, Université d´Abobo-Adjamé, Laboratoire d’Environnement et Biologie Aquatique, UFR-SGE, 02 BP 801, Abidjan 02, Côte d´Ivoire, E-Mail: [email protected]; Mark-Oliver Rödel, Humboldt University Berlin, Museum of Natural History, Herpetology, Invalidenstr. 43, D-10115 Berlin, Germany, E-Mail: [email protected].

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