ANARTIA

Publicación del Museo de Biología de la Universidad del Zulia ISSN 1315-642X


Anartia, 28 (junio 2019): 98-102



C. L. Barrio-Amorós

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Amphibians of Costa Rica. A field guide


Leenders, Twan


2016. San José: Zona Tropical Publication, Comstock Publishing Associates,

Cornell University Press, 531 pp. ISBN 978-0-9894408-3-7



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There is no doubt that Costa Rica has one of the best well-known Tropical herpetofauna in the world. It has been studied by single herpetologists and also teams for more than two centuries. It is also the only Neotropical country with more comprehensive books about its own herpetofauna (Savage 2002, Solórzano 2004, Kubicki

2004, 2007; Muñoz-Chacón & Johnston 2013, etc.).

For those reasons, everyone interested in amphibians and reptiles (professional or amateur) in Costa Rica were happy to have on hand several references that allow them to easily identify the species they could find over there (with only a few exceptions). However, the main refer- ence that was written so far, Savage’s masterwork (popu- larly called “the Bible”), has been paying the price of time. Treating it only the amphibians, it is now obsolete and has never been a true field guide. It was an encyclopedic volume that helps to identify the specimens once at home or at the laboratory. Kubicki’s two books about leaf frogs (Phyllomedusidae) and glass frogs (Centrolenidae) are very complete, but also suffer from becoming out of date and most of the species have changed their generic names ever since. The mini-guide by Muñoz-Chacón & Johnston (2013) is more recent, having scientific names in order, but the presented information is too basic to help identifica- tions, and the pictures are too small and not always good. The Amphibians of Central America by Köhler (2011) is a valid reference, and uses dichotomous keys that I am not sure how accurate they are, but also need important infor- mation about the morphology of each species; further, it has a wider scope and its strength is limited for Costa Rica. So, we herpetologists have so far believed to have all under control… until this new book arrived, making a triumphal entrance!

And that’s why. We really needed a modern book deal- ing with Costa Rican amphibians (as we do about rep- tiles!), presenting an easy way to check species and identify them. Maybe we did not miss it, but now that we have it, I really want to thank Twan for that marvelous present.

The book, in field guide format, is small and prepared for action. It is easily portable to the ground, making the identification an easy goal. How? Actually, this book has not dichotomous keys, however, they probably are a little obsolete as well. New generation field guides, led in the Neotropics by masterpiece Amphibians and Reptiles from

Recensión: Amphibians of Costa Rica. A field guide


Mindo Ecuador (Arteaga et al. 2013; see book review by Barrio-Amorós 2015), show a different panorama, with all species depicted in white background, and highlighting taxonomic characters useful to recognize every species. It is much more visual and appealing than boring and usu- ally difficult to interpret key. It is also outstanding how the author made not only the distribution maps, but also the technical drawings, and how he also prepared (and cut) all images to fit the white background rule.

Step by step, the book starts with a cover which actu- ally is not very appealing. For such a great effort inside, I think both the authors and editors should have selected a more interesting presentation. The letter font is ugly and the picture of a walking Agalychnis callidryas is predictable and non-breathtaking. The inside cover explains how the distribution maps are presented and show a small and con- venient map with ecoregions division of Costa Rica. It fol- lows explaining how to take measurements to caecilians, salamanders, and anurans. A foreword by Robin Moore and the acknowledgments by the author are next. An in- troduction to the book, talking about the geography, cli- mate and weather of the country, its ecoregions; a word on classification and scientific names, on how to observe and identify amphibians, and a necessary explanation about one of the amphibian modern nemesis, the amphibian de- cline, is after. Then, the author encourages readers to share their observations with other naturalists and specialists, as part of the newly recognized citizen science, which will be greatly benefited by this book.

Continues an introduction to each order; first the cae- cilians (same with salamanders and anurans), a very useful two pages pamphlet “Costa Rican Caecilians at a glance” (also the same later with salamanders and anurans) which depicts the three genera of the country with its main ex- ternal characters. In the case of “Costa Rican frogs and toads at a glance” every family is introduced with its main characters using a single species as a representative. For each Order, will appear a short introduction (in one page) to the family (e. g. Caeciliidae), another short introduc- tion on another page to each genus (e. g., Oscaecilia), and then, the formal account for each species. The accounts are usually two to three pages long, and include the scientific and common names, its IUCN status; a short paragraph of definition; a distribution map, highlighting by number the ecoregions where it is distributed, and a comment on the general and local distribution; a natural history section which is quite complete and resumes most of the general knowledge on the species in question (not as deep as in Savage 2002), and a description section with a picture of the taxon on white background, where external obvious characters are highlighted and pointed out, bringing the

attention of the reader to help identification. Finally, a very interesting and visual section is “Similar Species”, in which it is possible to check closely the main differences with most of their alike taxa.

A glossary of technical terms follows every account; then a Bibliography, very short to me, although it is not intended to provide an extensive list of references; fur- thermore, the author suggests consulting the references in Savage (2002) volume and some websites, among which, I miss the Amphibian Species of the World (Frost 2016). The penultimate section is devoted to credit the photos in the book, and the last is a taxonomic index, useful to quickly locate the species, genus or family. Two pages in blank for notes and the inside back cover is a little more detailed physical map of the country. The cover shows two short blurbs and a presentation of the book and its author.

Now that I have presented the book and that I really enjoyed reading it, there are some little details to mention, which I hope will help to improve a future edition.

There is mention of three species of salamanders and two frogs that have never been recorded for Costa Rica: Bolitoglossa indio, B. pygmea, Oedipina sp. (which very probably is the newly described O. berlini), Craugastor ch- ingopetaca and Pristimantis taeniatus. This is not bad per se… as the author states; B. pygmea is reported at 5 km of the border in Panama, therefore highly expected to occur in Costa Rica. Bolitoglossa indio was reported from close localities to the Costa Rican-Nicaraguan border, and one specimen is believed to be a record of this species from 1890. Of course, it can be very difficult to demonstrate this assessment without newly collected biological mate- rial. Pristimantis taeniatus, on the other hand, has been mentioned on an unpublished list from the Universidad de Costa Rica, and therefore it is included in the book without any distributional data. Gómez-Hoyos et al. (2018) will confirm the presence of the species through a picture taken recently.

I miss the accounts of some basic issues. First; scientific names should always be accompanied by their author(s) and year of description. This information helps to under- stand a lot about the history of the species at a glance. For example, if the species has been recently described or not, who is the authority to contact if the reader happens to have or require some information, etc. This should be linked to the reference (mentioned on the account and fully written on the bibliography section) of the original description. Also, there is no reason why there are sec- tions with an appropriate heading (like Natural History, Description or Similar species) and others not mention- ing it, as the Definition and Distribution. Also, and very important, it should be cited the origin of every speci-

C. L. Barrio-Amorós


men depicted, even if is not Costa Rica. As a photogra- pher, I would also like to see the photographer’s credits on each picture and not in a heavily charged page at the end. This gives information and makes easier to contact the photographer if you are interested in the species or locality. On the contrary, if you want to know who is the photographer of, for example, the lower right photo of Bolitoglossa alvaradoi on page 42, you go to page 525 and need to start searching among hundreds of very small page numbers.

Another issue that could be better resolved is the size of the letter font on the accounts. It is very small (am I picky with this? am I the only one who had a hard time reading the very small lines, especially under low light?) Probably my sight is becoming older and lazier. I know this is to save space!!

Only a few species lack their pictures, then it would be good to try an illustration of at least a preserved specimen.

A problem of design is that some species (e. g., Oe- dipina alfaroi, pp. 123) seem to have occupied only half page (and the remaining space white), which requires to turn to the next one to see the image of the species. This is confusing.

Dermophis gracilior (pp. 24) is a rare caecilian, but easy to distinguish due to its checkered belly. So, even if it is mentioned in the text, the best way to show it is with a good image.

About Bolitoglossa colonnea and B. striatula, both cases are common salamanders on the Caribbean versant or ecoregion 1, but they have been mentioned from the Pa- cific region without any proofs. These salamanders are dif- ficult to distinguish from B. lignicolor (which can also have a striped pattern) to non-specialists, and I think they do not occur in the area. However, they are worthy of men- tion as any new report would bring light to the subject.

I cannot be completely sure, but in my experience, the male Atelopus senex (pp. 156) looks to me like a female.

About Incilius fastidiosus (pp. 170-171), the picture bottom line says that that species is a “usual” little toad. Probably the author meant “unusual”, as nothing is nor- mal in that toad, not the shape, and not the abundance, as it has disappeared for a long time. In the Similar species section, there should be a reference to Incilius holdridgei, which is the most alike species.

After Acevedo et al. (2016) the common cane toad of Central America and those from South America west of the Andes became Rhinella horribilis instead R. marina. I am not sure if Twan had the time to check this before clos- ing the edition, but I see that there are even more recent data published which appear in the book.

Hyalinobatrachium fleischmanni is no longer recog- nized from Venezuela, as it says in pp. 208. Populations related to the species have been described as H. guai- rarepanensis and H. tatayoi recently (Señaris 1999, Castro- viejo et al. 2007, Barrio-Amorós 2004). The author also states that this species is likely the most frequently encoun- tered glass frog in Costa Rica. Well, this is so relative, as for me and according to my experience in the country, I have only seen two populations; it is true, however, that I don’t move much around the central mountains; but this is a matter of where each person looks for. In my area, Costa Ballena in the southern Pacific (Barrio-Amorós 2016), H. fleischmanni is absent, and other species are dominant.

On page 217, Sachatamia albomaculata is not men- tioned from Ecuador, and on pp. 219, Sachatamia ilex is mentioned on a locality (the Tarcoles river) where it has been accepted with doubts (Kubicki 2007).

On pages 227-228, the genus Craugastor is defined as containing some species groups, the fitzingeri s.g., the gollmeri s.g., the rhodopis s.g., the rugulosus s.g., and the bi- porcatus s.g. Actually, biporcatus is not a Craugastor, but a Strabomantis and the three species contained in Leenders’s classification (C. gulosus, C. megacephalus and C. rugosus) are currently being under a C. punctariolus species group (after Padial et al. 2014).

Furthermore, the Craugastor species groups used by Leenders are obsolete, and they must change as follows: the Craugastor gollmeri species group is now the C. laticeps series (after Hedges et al. 2008, Frost 2017). The Craugas- tor rhodopis species group is no longer stand, and all spe- cies in it belong to the C. podiciferus s.g. The Craugastor rugulosus species group as defined by Leenders must be understood as the C. punctariolus s.g.

Craugastor rugosus has become very scarce and difficult to observe, at least in the adult stage, while juveniles are often reported. I miss a picture of an adult specimen on its account.

Craugastor stejnegerianus is one of the most polychro- matic and abundant species of its genus; still, there are only two chromotypes depicted, which could lead to con- fusing many of these patterns with other species.

One of the most common mistakes that so many au- thors drag is to name familiarly the dendrobatid frogs as poison arrow or dart frogs. I really see this as confusing and misleading. Only two or three species (in the genus Phyllobates) are really used to poison darts (and none ar- rows), and they live in Chocoan Colombia. So, the rest of them, including all in Costa Rica, must be named poison frogs. To use the impractical and inadequate “dart” only generates more confusion.

Recensión: Amphibians of Costa Rica. A field guide


Treating Dendrobates auratus would be welcome to show the sexual dimorphism on the disk size and shape.

I also miss more chromotypes depicted for Oophaga granulifera, which is only shown as the Osa population (red anterodorsally and blue posteroventrally) and the Green one from Central Pacific. Where I live the chromo- type is red with only greenish blue hands and feet. Popula- tions northwards are yellow and orange.

Same is valid for Oophaga pumilio, a highly variable spe- cies. In Costa Rica, there are at least a dozen variants. De- picted is the typical blue jeans from La Selva and Sarapiquí to the North, and a reticulated variant (page 302) with no locality data.

Silverstoneia flotator, as all dendrobatids in Costa Rica, breeds in the rainy season. Its breeding activity is along the same season, never during the dry season, as the book states (pp. 310). It is true that during the dry season, many specimens can be gathering at small creeks and some can call, but this is not the real peak of breeding activity.

After Duellman et al. (2016) –probably the author did not receive the reference at time-, the panorama of the family Hylidae changed, and Phyllomedusidae raised to family in its own right. The author states that there are 8 species of the genus Agalychnis, which is not correct, being 13 after the change of the Phyllomedusa buckleyi group to the genus (Faivovich et al. 2010).

The size of the female of Agalychnis spurrelli is wrong, it says up to 72 mm, but Savage (2002) already stated that it was up to 93 mm. Populations from the southern Pa- cific are much smaller, with males up to 50 mm (Duellman 1970), and are differentiable from the larger Caribbean populations. I miss some information and at least a pic- ture of an individual of the Pacific populations, to be used for comparison. However, the maximum size mentioned in Leenders might refer to the mean between both data, instead of the maximum size for the species.

The genus Ecnomiohyla is no longer formed by 14 species but 12, after E. miotympanum and E. tuberculosa changed of the genus (now in the genera Rheohyla and Tepuihyla respectively after Duellman et al. 2016 and Ron et al. 2016).

Scinax elaeochrous is the proper naming for the species (not elaeochroa) since Scinax is masculine and not neuter (see Duellman et al. 2016).

About Engystomops pustulosus (pp. 451), there is a men- tion of the bat Trachops cirrhosus as predator, but the com- mon name used for it was wrong. I am not a friend of com- mon names, but in this case, I am sure Trachops is not the “common fishing bat”. I found a more accepted common name as a fringe-lipped bat.

About the size of Leptodactylus insularum, there is an error that has been dragged by Savage (2002) himself to date. For example, Savage (op. cit.) states that females of Leptodactylus insularum (as L. bolivianus in that book) are larger than males, and it is also repeated by Leenders. Ac- tually, males of many Leptodactylus species are larger than females, and so, males of L. insularum can reach up to 104 mm and females up to 99 mm (Heyer & De Sá 2011). Also, the main character to recognize and distinguish L. insularum among other congeners is the presence of two thumb spines, instead of one in L. bolivianus (Barrio- Amorós 2004), which should have been shown.

Since the publication of this very recent field guide, two latest publications added two new species to the Costa Ri- can panorama, reaching the number of 209 species. These new species added in 2016 are Bolitoglossa aurea Kubicki

& Arias, 2016, and Oedipina berlini Kubicki, 2016. Costa Rica, aside from its immense diversity does not seem to ex- pect many more discoveries of new amphibians as in other Latin American countries. The small size of the country

(51.11 km2) and the continuous work by many herpe- tologists from around the world in a territory filled with biological stations, make new taxonomic discoveries every day less probable. However, we are aware of some new sur- prises to arise soon enough.

This book, aside from its minor details, is a must in any herpetologist library, but very especially on Neotropi- cal research libraries, universities, and interested people. From any naturalist that comes to Costa Rica just for a few weeks to enjoy nature and photograph a few frogs, to the hardcore herper that needs all species identified on its list, Leender’s book will be highly appreciated.


REFERENCES


Acevedo, A., M. Lampo & R. Cipriani. 2016. The cane or marine toad, Rhinella marina (Anura, Bufonidae): two genetically and morphologically distinct species. Zootaxa 4103: 574–586. Arteaga, A., L. Bustamante & J. M. Guayasamin. 2013. The amphibians and reptiles of Mindo. Quito: Universidad Tec-

nológica Indoamerica, 258 pp.

Barrio-Amorós, C.L. 2004. Amphibians of Venezuela, sys- tematic list, distribution and references; an update. Revista Ecología Latino Americana 9: 1–48.

Barrio-Amorós, C.L. 2015. Book review. The amphibians and reptiles of Mindo. Life in the cloud forest. Herpetological Re- view 46: 111–113.

Barrio-Amorós, C.L. 2016. Amphibians and reptiles of Costa Ballena, Costa Rica. The Field Museum Guides 772: 1–9.

Castroviejo-Fisher, S., J. Ayarzagüena & C. Vilà. 2007. A new species of Hyalinobatrachium (Anura: Centrolenidae) from Serranía de Perijá, Venezuela. Zootaxa 1441: 51–62.

C. L. Barrio-Amorós


Duellman, W. E. 1970. Hylid frogs of Middle America. Mono- graphs of the Museum of Natural History, University of Kansas 1–2: 1–753.

Duellman, W. E., A. B. Marion & B.S. Hedges. 2016. Phylo-

genetics, classification and biogeography of the treefrogs (Amphibia: Anura: Arboranae). Zootaxa 4104: 1109.

Faivovich, J., C.F.B. Haddad, D. Baeta, K.H. Jungfer, G. F.R. Alvares, R. A. Brandao, C. Sheil, L.S. Barrientos, C. L. Barrio-Amorós, C. A.G. Cruz & W. C. Wheeler. 2010. The phylogenetic relationships of the charismatic poster frogs, Phyllomedusinae (Anura, Hylidae). Cladistics 26: 227–261. Frost, D.R. 2017. Amphibian species of the World: an online ref- erence. Version 6.0. Accessed in December 2017. Electronic Database is accessible at http://research.amnh.org/herpetol-

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Gómez-Hoyos, D., R. Méndez-Arrieta, A. Méndez-Arrieta,

R. Seisdedos-de-Vergara, J. Abarca, C. Barrio-Amorós & J. González-Maya. 2018. Anuran inventory in a locality of the buffer area of La Amistad International Park, Costa Rica: pi- lot study for citizen science application. Anales de Biologia 40: 57–64.

Heyer, R. & R. O. de Sá. 2011. Variation, systematics and re- lationships of the Leptodactylus bolivianus complex (Am- phibia: Anura: Leptodactylidae). Smithsonian Contributions to Zoology 635: 1–58.

Köhler, G. 2003. Reptiles of Central America. Offenbach: Her- peton, 367 pp.

Köhler G. 2011. Amphibians of Central America. Offenbach: Herpeton, 378 pp.

Kubicki, B. 2004. Leaf frogs of Costa Rica. Santo Domingo de Heredia: INBIO, 98 pp.

Kubicki, B. 2007. Ranas de Vidrio. Costa Rica glass frogs. Santo Domingo de Heredia: INBIO, 299 pp.

Kubicki, B. 2016. A new species of salamander (Caudata: Ple- thodontidae: Oedipina) from the central Caribbean foothills of Costa Rica. Mesoamerican Herpetology 3: 819–840.

Kubicki, B. & E. Arias. 2016. A beautiful new yellow salaman- der, genus Bolitoglossa (Caudata: Plethodontidae), from the northeastern slopes of the Cordillera de Talamanca, Costa Rica. Zootaxa 4184: 329–346.

Muñoz-Chacón, F. & R. D. Johnston. 2013. Amphibians and reptiles of Costa Rica. A pocket guide in English and Spanish. San José: Zona Tropical Publication: 215 pp.

Padial, J. M., T. Grant & D. R. Frost. 2014. Molecular system- atics of terraranas (Anura; Brachycephaloidea) with an as- sessment of the effects of alignment and optimality criteria. Zootaxa 3825: 1–132.

Ron, S. R., P. J. Venegas, M. Ortega-Andrade, G. Gagliardi-Ur- rutia & P. E. Salerno. 2016. Systematics of Ecnomiohyla tu- berculosa with the description of a new species and comments on the taxonomy of Trachycephalus typhonius (Anura, Hyli- dae). Zookeys 630: 115–154.

Señaris, J. C. 1999. Una nueva especie de Hyalinobatrachium (Anura: Centrolenidae) de la Cordillera de la Costa, Vene- zuela. Memoria de la Fundación La Salle de Ciencias Natura- les 152: 133–147.

Savage, J. M. 2002. The Amphibians and reptiles of Costa Rica: a herpetofauna between two continents, between two seas. Chi- cago: The University of Chicago Press, 934 pp.

Solórzano, A. 2004. Serpientes de Costa Rica: distribución, tax- onomía e historia natural / Snakes of Costa Rica: distribution, taxonomy, and natural history. Santo Domingo de Heredia: INBIO, 791 pp.


César L. Barrio-Amorós*


* Doc Frog Expeditions. E-mail: cesarlba@yahoo.com