Interciencia ISSN: 0378-1844 [email protected] Asociación Interciencia Venezuela

Duré, Marta I.; Kehr, Arturo I.; Schaefer, Eduardo F.; Marangoni, Federico Diversity of amphibians in rice fields from northeastern argentina Interciencia, vol. 33, núm. 7, julio, 2008, pp. 523-527 Asociación Interciencia Caracas, Venezuela

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How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Diversity of amphibians in rice fields from northeastern Argentina

Marta I. Duré, Arturo I. Kehr, Eduardo F. Schaefer and Federico Marangoni

SUMMARY

The anuran biodiversity and richness of a frog community in- etation was the most diverse of the microhabitats, while gullies habiting rice fields in northeastern Argentina was surveyed and were the poorest in species. The amphibian species of three of analyzed. The samples were taken between October 2001 and the microhabitats adjusted to the logarithmic range-abundance June 2003. Twenty six species of amphibians were identified in model, one to the geometric and one to the broken stick model. five microhabitats: rice fields per se, ditches and paths, natu- The data suggest that rice cropping in northeastern Argentina, if ral vegetation, aquatic vegetation and gullies. The natural veg- properly managed, can support a diverse anuran fauna.

DIVERSIDAD DE ANFIBIOS EN CAMPOS DE ARROZ EN EL NORESTE DE ARGENTINA Marta I. Duré, Arturo I. Kehr, Eduardo F. Schaefer y Federico Marangon RESUMEN

Se registró y analizó la diversidad y riqueza de una comuni- que las barrancas presentaron la menor cantidad de especies. El dad de anfibios que habita campos de arroz en el nordeste de modelo de rango abundancia serie logarítmica fue el de mejor Argentina. Las muestras fueron obtenidas en el período compren- ajuste para tres de los microhábitats analizados, otro se ajustó dido entre octubre 2001 y junio 2003. Se identificaron 26 espe- al modelo geométrico y el restante al modelo de varilla rota. Los cies habitando cinco microhábitats: campos de arroz, zanjas y datos sugieren que los cultivos de arroz del nordeste argentino, caminos, vegetación natural, vegetación acuática y barrancas. podrían albergar una fauna muy diversa si están sujetos a un La vegetación natural fue el microhábitat más diverso mientras manejo apropiado. diversidadE de anfÍbios eM campos de arroz NO nordeste da argentina Marta I. Duré, Arturo I. Kehr, Eduardo F. Schaefer e Federico Marangoni. RESUMO Registrou-se e analisou-se a diversidade e riqueza de uma co- quanto que as barrancas apresentaram a menor quantidade de munidade de anfíbios que habita campos de arroz no nordeste espécies. O modelo de espécie-abundância de série logarítmica da Argentina. As amostras foram obtidas no período compreen- foi o de melhor ajuste para três dos microhábitats analisados, dido entre outubro de 2001 e junho de 2003. Identificaram-se outro foi ajustou ao modelo geométrico e o último ao modelo 26 espécies habitando cinco microhábitats: campos de arroz, de vara quebrada. Os dados sugerem que os cultivos de arroz sulcos e caminhos, vegetação natural, vegetação aquática e bar- do nordeste argentino poderiam abrigar uma fauna muito diver- rancas. A vegetação natural foi o microhábitat mais diverso en- sa se estão sujeitos a uma manipulação apropriada.

Introduction 1997 to 1998 to ~86000ha and animal species (Bam- edges that delimit the plots. (Begenesic, 1998). baradeniya and Amerasinghe, The present study analyzes Rice cultivation in Ar- Rice fields also have a fun- 2003; Bambaradeniya et al., amphibian diversity and rich- gentina provides fundamen- damental role in the regula- 2004; Doody et al., 2004). ness in agricultural ecosys- tal contributions to the re- tion of local water and climate A field systematically set tems, particularly in rice fields. gional economies involved. cycles. The ecological features for rice cultivation possesses Amphibians are of interest The Province of Corrientes of the wetlands are a key for main and secondary channels because their special physi- is an important rice producer the preservation of wildlife in for irrigation water supply and ological (skin permeability) whose cultivated surface area these ecosystems, since they outlet, bounds that delimit the and ecological (compound two- increased considerably from harbor highly diverse plant cultivated paddies and interior phase life cycle) characteris-

KEYWORDS / Amphibians / Argentina / Biodiversity / Range-Abundance Models / Rice Fields / Received: 12/17/2007. Modified: 06/03/2008. Accepted: 06/05/2008

Marta I. Duré. Doctor in Natu- Argentina. Address: Cecoal. Arturo I. Kehr. Doctor in Natu- gentina. Researcher, CECOAL- ral Sciences, Universidad Na- Ruta Prov. Nº 5, Km 2.5. C.C. ral Sciences, UNLP, Argentina. CONICET, Argentina. cional de La Plata (UNLP), 140. C.P. 3400. Corrientes, Researcher, CECOAL-CONI- Federico Marangoni. Doctor Argentina. Researcher, Cen- Argentina. e-mail: martadure@ CET, Argentina. in Ecology, Universidad de tro de Ecología Aplicada del yahoo.com Eduardo F. Schaefer. Doctor in Sevilla, Spain. Researcher, CE- Litoral (CECOAL-CONICET), Natural Sciences, UNLP, Ar- COAL-CONICET, Argentina.

JUL 2008, VOL. 33 Nº 7 0378-1844/08/06/523-05 $ 3.00/0 523 tics happen to be potentially ing of shrubs and small sized Sampling methods The similarity between the excellent bioindicators, which trees; d) aquatic vegetation, specific composition of every in turn makes it very com- small ponds in which floating Sampling began in October microhabitat was estimated us- mon for amphibian populations aquatic plants had flourished, 2001 and was completed in June ing the Sorensen similarity in- to be severely affected when forming a layer that covered 2003, covering two continuous dex, which uses only binary there are serious disturbances the whole surface of the wa- rice cultivation cycles. The sam- information (presence/absence) to their natural habitats (Blaus- ter; and e) gullies, formations pling was initiated immediately and is calculated as tein and Belden, 2003; Carey that could be up to 20m deep, after completion of field prepa- S=2c/(a+b) and Alexander, 2003; Collins between rice plantations and ration work, which coincided and Storfer, 2003). river banks. with spring and sowing of the where a: number of taxa present Given that rice fields have rice, and continued till the fal- in sample A, b: number present heterogeneous ecological con- Agricultural practices low period. The sampling was in sample B, and c: number of ditions, organisms that live carried out fortnightly, during taxa that are present in both in this habitat must be well For four years prior to this day (18:00) and night (23:00), samples. adapted to continuous changes study, agricultural activities on each session spanning 2.5h. A The Sorensen index can be and their survival will depend the site being monitored were total of 41 sampling sessions also quantitative (species and both on their physiological related entirely to rice culti- were carried out during the en- their abundances in common). characteristics and their ability vation. Preliminary sampling tire survey period. This is one modification of the to migrate. Moreover, agro- began in August, followed in The capture method was Bray and Curtis (1957) formula nomic practices carried out in October by flooding of the manual, with nets, using a and frequently named as So- rice cultivation, for example field with water extracted from sampling methodology known rensen index (Magurran, 1988): when ploughing the fields, ap- the Parana River and, also, wa- as “visual encounters surveys” C = 2jN/(N +N ) plying of herbicides, fertilizers ter distribution to the channels (Heyer et al., 1994). Each sam- N a b and fungicides, and frequent by means of pumping stations. pling was carried out by the where Na: total number of in- adjustments of the water level, The crop period lasted ~100 same three people and each dividuals in site A, Nb: total are considered limiting factors days. Immediately after the microhabitat was supervised number of individuals in site B, for amphibians that inhabit crop was harvested, in Febru- for 30-40min in order to avoid and 2Jn: sum of the lowest of these ecosystems (Bambarad- ary and April, the plots were underestimation of the biodi- the two abundances for species eniya, 2000). prepared for a new sowing. versity. Amphibian specimens found in both sites (Magurran, The aim of this study was to During the period between were captured inside the rice 2004). determine amphibian diversity crop harvest and sowing (fal- field, in channels that take the The community composition and species richness in rice low period), the field retained water from the river up to the for each microhabitat was char- fields in the Corrientes Prov- some water in the channels of plantation and connect different acterized by means of the range ince in relation to the different irrigation and drainage, as well sowed areas, and at relictual - abundance models. For every microhabitats formed inside as in small temporary pools in vegetation that remains inside case, it was specified which of this particular environment. rice fields. the area of study. The sub- the more common three series, Generally, in the rice fields stratum on which specimens logarithmic, geometric and “bro- Materials and Methods of the Corrientes Province, were found at the moment of ken stick”, presented a better herbicides such as glypho- capture and their behavior (i.e. adjustment to the observational Study Site sate or N-(fosfometil) gly- singing and/or listening) were data. The comparisons between cine (3-6l·ha-1) are applied noted. different variables were done by This study was conducted in before sowing for the control On each sampling day, the means of the Chi-square test. a rice field located 30km south of grasses. After germina- presence of anurans was re- To avoid underestimation of of the city of Corrientes, in the tion, when the plants are 7-10 corded by direct observations the population in some micro- Corrientes Province (27º47′S, days old, fertilizer is added or by auditive identification. The habitats, due to differences in 58º46′W), with a surface of (NPK= 5-30-15 or 5-30-20) captured specimens were identi- sample size or to the difficulty ~1000ha. A reconnaissance for a final 2N concentration of fied using various guides and to reach the specimens, the rar- survey was conducted prior to 150-180kg·ha-1 and urea con- keys (Cei 1980, 1987; Gallardo efaction model proposed by carrying out the field sampling, centration of 100-120kg·ha‑1. 1987; Frost 2004; Faivovich et Sanders (1968) and corrected in order to select, within the Fertilization is generally per- al., 2005; Frost et al., 2006). by Hurlbert (1971) and by Sim- study site, different habitats for formed in fractional appli- berloff (1972) was used. This the survey. cations, with half or 70% Data analysis procedure allows to compare Five dominant microhabi- in pre-watering and the re- the species richness and diver- tats were selected in rice field mainder during FPD (foliate Diversity was calculated by sity in different environments, habitats. These were a) rice primordial differentiation). the Shannon diversity index regardless of the sample size. fields per se, an area where During flowering, insecticides (Shannon and Weaver, 1949), The samples were rarefied to rice was sowed and cultivated; are applied for the control of using natural logarithms. The the smallest sample size. The b) ditches and paths, which ants (Fipronil) and bedbugs specific diversity for each mi- richness and diversity results included the paths and ditch- (Metamidofos). Other pesti- crohabitat was obtained by were obtained for five classes es on both sides of the rice cides, such as deltametrine means of the method proposed of abundance (5, 10, 15, 20 and fields and routes that linked and dimethoates, are also by Zar (1996). Every calculation 25 individuals). Subsequently, the different sowed plots; c) used. Fungicides were only was made by using the Bio-Dap the microhabitat diversity for natural vegetation, an area in- used on a small scale and software (Thomas and Clay, each one of the five classes of side the rice-field which was were generally mixed. The 2000), which is based on the abundance was compared with not sowed, often resulting in fumigation process was car- methods proposed by Magur- the non-parametric Kruskall- the natural vegetation consist- ried out by airplane. ran (1988). Wallis test.

524 JUL 2008, VOL. 33 Nº 7 2 Results dance (x (with Yates correction for continu- Table II ity)= 1.34, df= 1, p= 0.24). The Range - abundance series for each of During the first year of sam- highest abundance of different the microhabitats considered in a rice pling, the flooding of the rice species were observed during field NEAR Corrientes, Argentina field began in September 2001 autumn (N= 474) and spring Microhabitats Series X2† df† Significance Diversity and the crop was harvested in (N= 439), which coincided (Shannon Jan-Mar 2002. The second year with the respective emptying index) it began in Sep 2002 and the and flooding of the field. This Ditches and paths Logarithmic 14.13 7 14.06* 2.07 crop harvesting took place in number decreased slightly in Rice-field Logarithmic 4.31 6 12.59 2.08 Apr 2003. summer (N= 330), during this Aquatic vegetation Logarithmic 1.51 5 11.07 1.69 A total of 1380 individuals period when the emptying of Natural vegetation Broken stick 2.92 5 11.07 2.36 were collected, belonging to the field occurs and the labor Gullies Geometric 0.50 3 7.81 0.91 four families: Cycloramphidae, related to rice harvest starts. † x2: chi square, df: degrees of freedom, significance: p≤0.05 (*). Bufonidae, Hylidae and Lep- In contrast, the lowest abun- todactylidae, and appertaining dance of amphibians was re- to 26 species of amphibians corded during the winter (N= subfamily was represented only the aquatic vegetation, fitted (Table I). 137), which coincides with by Lysapsus limellum. This spe- this series better. low temperatures and, towards cies was only found on two oc- The natural vegetation mi- Seasonality the end of winter, ploughing casions, in Feb and Mar 2002. crohabitat presented the highest the field. The Microhylidae family was specific diversity and it was fit- Significant differences were The Leptodactylidae family, represented in this area by Ela- ted to the “broken stick” model observed in species abundance with 10 species, was the most chistocleis bicolor, although series, which represented a more in the four seasons of the year abundant family in the rice field only tadpoles and vocalizations suitable species abundance dis- (x2= 199.90, df= 3, p<0.0001). and was found in every sample. were registered in Dec 2001 tribution. The lowest number of Autumn and spring did not Bufonidae and Hylidae were and Sep 2002, and the family taxa was registered in the gul- witnessed any significant dif- most abundant during the spring Cycloramphidae was represented lies, thus fitting the geometric ferences in relation to abun- and summer and the Pseudidae by Odontophrynus america- series (Table II). nus a species captured in the The greatest similarity, in months of May and September. qualitative and quantitative TABLE I The most common species were terms, was observed between List of amphibian species in a rice field Leptodactylus chaquensis (N= the rice field and the ditches locaTED 30km from CIUDAD Corrientes, 317), Pseudopaludicola falcipes and paths linking the different Argentina (N= 300) and Dendropsophus cultivated sectors. In contrast, nanus (N= 194). All frogs were the gullies and the natural veg- Family Species collected during the winter, de- etation presented the greatest Microhylidae Elachistocleis bicolor* spite the evident decrease in difference from a qualitative activity during these months point of view, and the gullies Cycloramphidae Odontophrynus americanus (N=2) demonstrated by the majority and the ditches and paths in of species. quantitative terms (Table III). Bufonidae Chaunus schneideri (N= 57) Significant differences were Chaunus granulosus (N= 3) Microhabitat preferences observed in the diversity of Chaunus fernandezae (N= 16) microhabitats, with the excep- Chaunus bergi (N= 42) The natural vegetation was tion of the comparison between the most diverse microhabitat ditches and paths and the rice Leptodactylidae Leptodactylus (Lithodytes) diptyx (N= 7) (H’= 2.36, E= 0.82, N= 236). field (Table III). The Anuran Leptodactylus podicipinus* Thereafter, in decreasing or- families observed were rep- Leptodactylus elenae (N= 5) Leptodactylus latinasus (N= 70) der, the rice field (H’= 2.08, resented in a different way in Leptodactylus chaquensis (N= 317) E= 0.77, N= 296), ditches and those microhabitats. Leptodactylus ocellatus (N= 9) paths (H’= 2.07, E= 0.70, N= In order to compare richness Pseudopaludicola boliviana (N= 32) 723) aquatic vegetation (H’= and diversity amongst the five Pseudopaludicola falcipes (N= 300) 1.69, E= 0.74, N= 100), and microhabitats, the calculations Physalaemus santafecinus (N= 91) gullies (H’= 0.91, E= 0.66, were rarefied to the smallest Physalemus albonotatus (N=12) N= 25). The distribution of sample, e.g. gullies (N= 25; species abundance in the mi- Table IV). Hylidae Lysapsus limellum (N= 4) crohabitats was adjusted to The majority of the species Hypsiboas raniceps (N= 4) different series of the range belonging to the Leptodactyli- Hypsiboas pulchellus (N= 13) - abundance model (Table dae family were observed inside Dendropsophus nanus (N= 194) II). Even though the distribu- the rice field and prior to the Dendropsophus sanborni (N= 93) tion of species abundance in flooding phase. Once flooded, Scinax fuscomarginatus (N= 22) ditches and paths did not fit they were observed preferably Scinax nasicus (N= 7) any of the series models, it in the shores of the channels Scinax acuminatus (N= 76) came close to being within and paths. The fossorial species, Argenteohyla siemersii (N=1) the limits of the logarithmic such as Leptodactylus latinasus, Phyllomedusa hypochondrialis (N= 3) distribution model (Table II). L. elenae or L. (Lythodytes) * Species identified only by calling or presence of tadpoles. N: number of Nevertheless, other microhabi- diptyx frequented areas with individuals recorded, tats, such as the rice field and dense vegetation in those sec-

JUL 2008, VOL. 33 Nº 7 525 Table III sects and crabs (Bambaradeniya Values of similarity (orensen’s index) and comparative analysis and Amerasinghe, 2003). of diversity index for each microhabitat identified in a rice Rice production may have field near Corrientes, Argentina demonstrable positive effects inasmuch as the required cre- Ditches and Rice-field Aquatic Natural Gullies paths vegetation vegetation ation of large flooded areas that must be maintained for extended Ditches and paths Qu= 0.88† Qu= 0.69 Qu= 0.70 Qu= 0.34 periods represents a viable al- Qt= 0.55† Qt= 0.23 Qt= 0.36 Qt= 0.06‡ ternative to natural wetlands in t= 0.16 t= 4.01 * t= 4.12 * t= 6.84 * providing reproductive habitats df= 598.87 df= 144.61 df= 461.39 df= 27.86 for anurans (Baker and Halliday, Rice-field Qu= 0.64 Qu= 0.72 Qu= 0.42 1999; Knutson et al., 2004). Qt= 0.39 Qt= 0.47 Qt= 0.15 Indeed, some authors character- t= 3.81 * t= 3.45 * t= 6.72 * ize rice fields as an important df= 190.25 df= 517.71 df= 30.97 man-made habitat for amphib- ians (Bambaradeniya and Am- Aquatic vegetation Qu= 0.50 Qu= 0.43 erasinghe, 2003) and suggest Qt= 0.53 Qt= 0.32 that appropriately managed rice t= 6.43 * t= 4.20 * fields may somewhat ameliorate df= 196.81 df= 39.64 shrinking global habitats for Natural vegetation Qt= 0.15 ‡ anuran amphibians (Fujioka and t= 8.28 * Lane, 1997; Elphick, 2000). df= 31.65 There are many negative side Gullies effects, such as the loss of natu- ral habitats, isolation, the harm- Qu: qualitative, Qt: quantitative, df: degrees of freedom. † : maximum and ‡ : minimum values obtained. ful use of herbicides and the * Significant differences between microhabitats (p<0.05). systematic flooding and draining of these plantations, all of which tors that were kept unsown (e.g. chondrialis, remained in areas of microhabitats suitable for the could directly affect amphibian the natural vegetation). covered by dense vegetation sustenance of a diverse anuran life cycles (Fujioka and Lane, The two specimens found bordering the sowed rice field fauna that approximates what 1997; Knutson et al., 2004). that corresponded to the Cy- areas near the water reservoirs. might be found in undisturbed The present study showed cloramphydae Odontophrynus Argenteohyla siemersii, on the wetlands, a fact previously rec- five distinctly different habitats americanus were found in the other hand, was observed very ognized by Bambaradeniya et defined by structure and plant ditches and paths that connect sporadically within natural veg- al. (2004). species composition, and by the paddy fields, always on dry etation on Gramineae plants ex- The environmental impact the water availability. It is not land. ceeding 1m in height. Lysapsus produced by rice plantations surprising that, of the delineated Concerning Bufonidae, before limellum was found inside the varies depending on production microhabitats, natural vegeta- the flooding phase it was com- irrigation channels, in areas methods (Donald, 2004) but tion supports the highest diver- mon to find specimens inside inundated with water ~70cm in there is the possibility of affect- sity and species richness. The the rice field. However, after the depth, where aquatic plants also ing amphibian ecology, ethol- rice production system studied flooding phase the individuals grew alongside floating leaves. ogy and distribution in some employs an irrigation system were observed on the slopes of The call of the Microhylidae areas (Fujioka and Lane, 1997). that is intermediate between the channels. Elachistocleis bicolor was re- Nevertheless, this environmental the “old-style” and “new-style” As soon as the rice field corded in the surrounding areas impact should not necessarily be irrigation methods (Fujioka and was flooded, and by the time of the irrigation channels, inside classified only in negative terms, Lane, 1997) and contains ele- that the crop had reached ap- natural vegetation. given that this type of farming ments of both. The study site proximately 30cm in height, practice, due to the particular contained fields irrigated with some species of Hylidae, such Discussion characteristics of its water man- water taken from the Parana as Dendropsophus nanus, Sci- agement, can provide an impor- River and raised by pumps to nax acuminatus and S. fusco- This study shows that irri- tant source of microhabitats for an earthen distribution system marginatus, were frequently gated rice fields in northeastern amphibians. Anurans are im- consisting of a network of shal- observed inside the field. Other Argentina are more than an portant natural enemies of pest low ditches. Field drainage is larger hylids, such as Hypsiboas agricultural enterprise. Rice pro- insects, and some species act as likewise through earthen ditch- raniceps or Phyllomedusa hypo- duction currently creates a mix biocontrol agents of rice pest in- es that support the growth of aquatic and terrestrial vegeta- tion. Minimal structural changes Table IV carried out on rice fields would Average (±SD) richness and diversity for each microhabitat identified probably prevent a drastic de- in a rice field near CIUDAD Corrientes Argentina crease in frog population. Ditches and Rice fields Aquatic Natural Gullies Spring is the most favorable paths vegetation vegetation season for studies related with the anuran communities in the Richness 8.26 ±1.38 8.61 ±1.22 6.38 ±1.06 9.96 ±1.45 4 ±0 rice field, because during these Diversity 1.79 ±0.17 1.83 ±0.17 1.55 ±0.14 2.04 ±0.14 0.91 ±0 months the highest richness and diversity were registered.

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This encouraging Magurran AE (2004) Measuring versity of anuran populations result invites further research Collins JP, Storfer A (2003) Global Biological Diversity. Black- in rice cropping. This arrange- designed to evaluate the impact amphibian declines: sorting the well Publishing. Oxford UK. hypotheses. Divers. Distrib. 256 pp. ment, together with the use of less obvious rice production 9: 89-98. of earthen irrigation distribu- factors on anuran communities Sanders HL (1968) Marine benthic Donald, PF (2004) Biodiversity diversity: a comparative study. tion ditches, seems to assure and to optimize the benefits impacts of some agricultural Am. Naturalist 102: 243-282. that rice fields per se can serve of management practices with commodity production systems. Cons. Biol. 18: 17-37. Shannon CE, Weaver W (1949) as significant habitats for an- negligible costs, and to evaluate The Mathematical Theory of Doody SJ, Osborne W, Bourne D, urans, because frogs and toads the possible production benefits Communications. University Bronwyn R, Sims R (2004) of Illinois Press, Urbana, IL. and their larvae can use unim- obtained by anuran biological Vertebrate biodiversity on Aus- 144 pp. proved channels for dispersal control of crops. tralian rice farms. Rural Indus- from natural vegetation into tries Research and Development Simberloff DS (1972) Properties of the rice fields when conditions Acknowledgments Corporation. Australia. 185pp. the rarefaction diversity mea- surement. Am. Naturalist 106: Elphick CS (2000) Functional equiv- in the fields are favorable (i.e. 414-418. flooded). Bambaradeniya et The authors thank M. Fu- alency between rice fields and seminatural wetland habitats. Thomas G, Clay D (2000) BIO- al. (2004) found that aquatic jioka for reviewing an early Cons. Biol. 14: 181-191. DAP- ecological diversity and organisms were able to use version of the manuscript and Faivovich J, Haddad CFB, García its measurement. Resource dry rice field soil cracks and Robert L. Smith for English re- PCA, Frost DR, Campbell JA, Conservation. Fundy National crevices for aestivation when vision. This work has been sup- Wheeler WC (2005) System- Park. New Brunswick, Canada. atic review of the frog family (http://nhsbig.inhs.uiuc.edu/ the fields were drained. This ported in part by the Consejo populations/bio-dap.zip). finding is cooroborated by the Nacional de Investigaciones Hylidae, with special refer- ence to Hylinae: phylogenetic Zar JH (1996) Biostatistical Analy- present study, having found Científicas y Técnicas (CONI- analysis and taxonomic re- sis. 3rd ed. Prentice Hall. Up- Chaunus bergi and Leptodac- CET), Argentina, through grant vision. Bull. Am. Mus. Nat. per Saddle River, NJ, USA. tylus chaquensis in cracks after PIP 2766 to AIK. Hist. 294: 1-240. 917 pp.

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