Senckenberg Research Institute and Natural History Museum Frankfurt

Herpetology

Our research activities focus on the Neotropical herpetofauna (Central and South America, Mexico, and the West Indies).  Formerly, we carried out additional research activities in Malawi.

The basis of our research is usually a species inventory of the given region with a taxonomic treatment of its faunal elements. Then, based on external morphological traits, genital morphological data, and molecular genetic markers, we evaluate the phylogenetic relationships of the species in question and establish hypotheses for the evolution of the studied taxa. Statistical analyses of the zoogeography of the species assembledges are also part of our work.

Since 1995, the genus Anolis is the animal group we have studied most intensively. More than one third of the 96 species of Anolis currently known to occur in Central America have been described or resurrected by us. With close to 400 recognized species, the genus Anolis provides great opportunities to study various aspects of speciation.

 Diversity of Herpetofauna

Diversity, taxonomy, and phylogeny of the herpetofauna of Latin America

Since 1995 we have conducted herpetological research in all Central American countries, as well as in selected South American countries. Projects on the Antilles are in preparation. We plan to do fieldwork on Hispaniola in October and November of this year. Thus, we have established excellent contacts and some long-term colaborations with scientists, universities, museums, and ministries in Latin America. The Senckenberg herpetological laboratory in Frankfurt, Germany, is the only lab in the world that is undertaking projects on the diversity, taxonomy, and phylogeny of the herpetofauna throughout Central America (Mexico, Belize, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica, and Panama). This makes possible large-scale comparisons and, in some cases, this can highlight problems that would otherwise not be visible or obvious, e.g., the study of the geographic variation of a “species” that is subsequently understood to represent actually a complex of species. Also for the evaluation of supra-regional phenomena such as population dynamics in anurans, this holistic perspective is helpful because it makes it easier to detect patterns.

For the past several years, the focus of our herpetological research in South America has been in Bolivia, Paraguay, Peru, and Ecuador. In Bolivia, Senckenberg has established a Research Station (Ecological Research Station Chiquitos, San Sebastian) providing an infrastructure that has allowed the completion of two doctoral dissertations and several undergraduate research projects. In Costa Rica, we are the leading partners in a long-term herpetology monitoring project.

Aside from numerous publications in international journals, the results of our work in Latin America has resulted in the publication of several books on the diversity, taxonomy, and identification of the Central American herpetofauna, as well as several regional identification guides. Two of the more prominent works are the following comprehensive monographs on the herpetofauna of Central America:

Köhler, G. (2008): Reptiles of Central America. 2nd edition. Offenbach (Herpeton), 400 pp.
Köhler, G. (2011): Amphibians of Central America. Offenbach (Herpeton), 379 pp.


Diversity, taxonomy, and phylogeny of anoles (genus Anolis)

The anoles (Anolis sensu lato), with close to 400 recognized species, represents the most diverse lizard genus, with more species being described almost every year. The phylogenetic relationships and taxonomy of this group of lizards remain subject to serious controversy in the recent literature. Indeed, our understanding of the systematics of these lizards is still at a low level. For most “species groups” of anoles, as proposed by various researchers in the literature, the evidence that these actually represent monophyletic groups is meager. Some of them probably are natural groups of species, while others represent artificial groupings of species that are simply similar and are placed together because of particular character resemblances.

Based on morphological characteristics, such as pholidosis, body proportions, osteology, and hemipenial morphology, the Central American anoles are being revised. In addition to fieldwork in the natural habitat, the extensive collections in European, North American, and Central American museums are being integrated into this study.

Hemipenial morphology as a source of information for systematics and taxonomy in anoles had received relatively little attention in the past. A comparative study of shape and surface ornamentation of the male copulatory organs indicates an enormous diversity in these lizards. Intraspecific and geographic variation is negligible, whereas there is substantial variation among species. We have documented 12 species pairs of Central American anoles that are extremely similar in their external morphology (scalation and morphometrics), but differ drastically in their hemipenial morphology. Typically, one of the species in each pair has a large bilobed hemipenis whereas the other has a small unilobed organ. Thus, these are cryptic species that were differentiated based on their divergent hemipenial morphology. In all cases studied, we found a close correlation between female cloacal morphology and male hemipenial morphology.

We can assume that differentiation took place in isolation (allopatry) with males and females coevolving. The available molecular data indicate a close relationship of the differing hemipenial morphs. This situation suggests that changes in genital morphology evolve very quickly in Anolis, probably by a self enhancing process like “runaway evolution by cryptic female choice” or “chase away evolution by sexual conflict.”

Anolis_01

Along contact zones between closely related species, individuals with intermediate hemipenal morphologies are found, indicating that hybridization occurs. This is confirmed by looking at hemipenial morphology of hybrids produced in the laboratory. This phenomenon raises the question of functional neutrality for anole genital morphology. Female cloacal morphology closely matches the hemipenial morphology of sympatric males. Thus, hemipenial morphology is probably not functionally neutral. However, there is no evidence of reinforcement along contact zones of closely related anole species. Differences in hemipenal morphology does not prevent hybridization, indicating that a “key-lock” mechanism is not operating in anoles.

Anolis_02

Genital morphology in anoles is an understudied yet promising area of research. There are many potential projects for investigating the role that genital morphology plays in speciation in the genus Anolis, including the mating systems in anoles, processes during copulation, sperm storage, and the effects of genital morphology on sperm storage.

Publications

 

Taxonomic studies of selected genera of the family Gymnophthalmidae

The family Gymnophthalmidae is sometimes collectively called the microteiids because this assemblage of several hundred, mostly small bodied species was historically recognized as a subfamily of the Teiidae. Based on morphological characteristics (pholidosis, body proportions, and hemipenial morphology), selected genera of this family are being revised. We aim to clarify existing taxonomic issues, provide a synopsis of the morphological variation of the species studied, an identification key to the genera (restricted to a certain country if useful), and dot distribution maps. Aside from fresh collections obtained during our own fieldwork, we aim to include in our revisionary work as many specimens as possible from existing collections worldwide.

So far, the results of the revisions of the genera Alopoglossus, Echinosaura, Euspondylus, and Proctoporus have been published, including the descriptions of a new species of Echinosaura, three new species of Euspondylus, and two new species of Proctoporus.


Research and conservation project Utila Iguana

The Utila Iguana (Ctenosaura bakeri) is a large iguanid lizard that is restricted to the small Caribbean island of Utila (Islas de la Bahia, Honduras) and threatened by extinction due to overhunting and loss of habitat. The "Research and Conservation Project Utila Iguana" was established in 1994 as a joint project by the Frankfurt Zoological Society and the Senckenberg Nature Research Society. As originally planned, in 2008, the responsibility and leadership of the project was transferred to the Bay Islands Foundation.

The goal of the project is the long-term conservation of Ctenosaura bakeri in its natural environment on Utila. The primary activities of the project are to develop a broad education and information program for the local community, investigate the natural history and reproductive ecology of C. bakeri, establish and maintain a headstart program, and protect iguana habitat on Utila.

For volunteers, the "Conservation Project Utila Iguana" offers a multitude of tasks and activities at the "IGUANA Research & Breeding Station" on Utila, including environmental education, public relations, animal care, gardening, station maintenance, and ecological research, to name a few examples.

http://www.utila-iguana.de/

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

C. bakeri

 Male Utila Iguana (Ctenosaura bakeri)

 

https://die-welt-baut-ihr-museum.de/en