Taxonomy, zoogeography, and conservation of the herpetofauna of Nicaragua [Elektronische Ressource] / von Javier Sunyer Mac Lennan

Javier Sunyer

Informations

• Publié par: goethe_universitat_frankfurt_am_main
• Publié le: 01 janvier 2009
• Nombre de lectures: 14
• Langue: English
• Poids de l'ouvrage: 10 Mo

Extrait

Taxonomy, zoogeography, and
conservation of the herpetofauna of
Nicaragua

Dissertation
zur Erlangung des Doktorgrades
der Naturwissenschaften


vorgelegt beim Fachbereich Biologie
der Goethe-Universität
in Frankfurt am Main


von
Javier Sunyer Mac Lennan
aus Madrid, Spanien

Frankfurt am Main, 2009

Gedruckt mit Unterstützung des Deutschen Akademischen Austauschdienstes

vom Fachbereich Biowissenschaften der Goethe-Universität als Dissertation
angenommen.



Dekan: Prof. Dr. Volker MÜLLER
Gutachter: Prof. Dr. Bruno STREIT (Frankfurt am Main)
Prof. Dr. Wolfgang BÖHME (Bonn)
Datum der Disputation:


iiABSTRACT
Central America is one of the world’s most herpetological diverse areas in relation to its
size. Nicaragua is the largest country in this region and separates Nuclear from Lower
Central America. It is one of the least herpetological explored countries in Central
America and few studies dealing with the herpetofauna of a potion or the entire country
have been published. I here update the checklist of the Nicaraguan herpetofauna, present
taxonomic revisions of some difficult species complexes, compare the similarities of the
composition of the herpetofaunal communities in the major forest formations present in
the country within a zoogeographical context, and identify those species with a greater
vulnerability risk in Nicaragua.

Taxonomy
The herpetofauna of Nicaragua currently consists of 244 species representing 134 genera
and 42 families with 78 amphibian species representing 35 genera and 15 families, and
166 reptile species representing 99 genera and 27 families, which includes six marine
species. Sixteen species (12 amphibians and four reptiles) are endemic to the country. Of
the 12 endemic amphibian species, three are here described. In addition, five genera
(Anotheca, Cerrophidion, Duellmanohyla, Isthmohyla, and Rhinobothryum) and two
species (Rhadinea godmani and Urotheca decipiens) are known to occur both north and
south of Nicaragua although there are no voucher specimens of these taxa to confirm their
presence in country.
I complete a bibliographic research updating the nomenclature changes and provide a
brief herpetological history of Nicaragua, a recompilation of all species described upon
Nicaraguan material and their current synonymy, the first time each species was recorded
from the country, and a list of all recognized subspecies occurring in Nicaragua. I discuss
the taxonomic uncertainties among the Nicaraguan populations of amphibians and
reptiles and take further detailed taxonomic revisions on selected Nicaraguan species
groups from the genera Anolis, Bolitoglossa, and Craugastor along their known
distributional range. I describe five new species of herpetofauna (three of which are based
on Nicaraguan material), redescribe five species of Anolis (three of which occur in
iiiNicaragua), and provide voucher specimens of five other species for the first time in
Nicaragua. In detail:
• I studied the pholidosis, morphometrics as well as hemipenis and dewlap
morphology in Anolis wermuthi, an anole endemic to the highlands of northern
Nicaragua. I examine patterns of geographic variation using discriminant function
analysis and discuss the characters that vary both individually and among
populations. The results indicate that A. wermuthi is a single species with several
disjunct, slightly divergent populations. I provide a standardized description,
illustrations of the everted hemipenis of an adult topotype, the male and female
dewlap, and a distribution map. I also provide brief descriptions of the localities
where this species occurs and some ecological notes.
• I studied the pholidosis, morphometrics as well as hemipenis morphology in the
Central American anole species Anolis humilis, A. quaggulus, and A. uniformis.
The three taxa are distinct in hemipenis morphology. However, very little
differentiation in pholidotic and morphometric characters is documented. I
document interspecific variation in several characters but with overlap of the
documented ranges. A discriminant function analysis based on five pholidotic
characters yielded a scatter diagram that showed large overlap between the
clusters of the three taxa. I provide head scalation illustrations, an identification
key, a distribution map, and standardized descriptions of the commonly
distributed in Nicaragua A. quaggulus as well as of the other two species.
• I describe two new species of anoles (genus Anolis) from Panama formerly
referred to as Anolis limifrons. The two new species, Anolis apletophallus and
Anolis cryptolimifrons, differ from A. limifrons by having a large bilobed
hemipenis (small and unilobed in ). The new species differ from each
other in male dewlap size and coloration. I provide illustrations of the head
scalation, everted hemipenis, and dewlap, an identification key, a distribution
map, and standardized descriptions of the commonly distributed in Nicaragua A.
limifrons and the two new species described herein.
• I describe two new species of salamanders of Bolitoglossa from southern
Nicaragua. Bolitoglossa indio is known from Río Indio in the lowlands of the Río
San Juan area and Bolitoglossa insularis from the premontane slopes of Volcán
ivMaderas on Ometepe Island. The two new species are of unknown affinities but
both differ from their congeners in coloration. Bolitoglossa indio is most similar
to B. mexicana and B. odonnelli from which differ by having both broad
dorsolateral pale brown stripes not clearly delimited in outline. Bolitoglossa
insularis is most similar to B. mombachoensis and B. striatula from which differ
by the absence of dark or light defined stripes on dorsum and venter.
• I describe a new species of frog of the genus Craugastor from Río San Juan,
Nicaragua. The new species, Craugastor chingopetaca, is assigned to the
fitzingeri group and differs from most Central American species of that group by
the absence of a midgular pale stripe. Within the fitzingeri group it is most similar
to C. crassidigitus and C. talamancae from which it differs in several
morphological characteristics such as more extensive webbing, retuse disk covers
on some digits, and relative toe length.
• I provide voucher specimens of Cochranella spinosa, Kinosternon angustipons,
Mesaspis moreletii, Cnemidophorus lemniscatus and Adelphicos quadrivirgatum
for the first time in Nicaragua. I include descriptions, illustrations, and brief
ecological notes for the five new country records.

Zoogeography
Based on the concept of ecological formations proposed by HOLDRIDGE (1967), nine
forest formations are found in Nicaragua. Of the total number of terrestrial species of
herpetofauna found in Nicaragua, 131 species (55.0%) occur in Lowland Wet Forest, 21
of which (8.8%) are restricted to this forest formation, 168 species (70.6%) occur in
Lowland Moist Forest, 15 of which (6.3%) are restricted to this forest formation, 84
species (35.3%) occur in Lowland Dry Forest, four of which (1.7%) are restricted to this
forest formation, 47 species (19.7%) occur in Lowland Arid Forest, with no species
restricted to this forest formation, 59 species (24.8%) occur in Premontane Wet Forest,
three of which (1.3%) are restricted to this forest formation, 116 species (48.7%) occur in
Premontane Moist Forest, 10 of which (4.2%) are restricted to this forest formation, 51
(21.4%) species occur in Premontane Dry Forest, with no species restricted to this forest
formation, 13 species (5.5%) occur in Lower Montane Wet Forest, two of which (0.8%)
vare restricted to this forest formation, and 50 species (21.0%) occur Lower Montane
Moist Forest, seven of which (2.9%) are restricted to this forest formation.
The Coefficient of Biogeographic Resemblance algorithm show a distinct composition of
the herpetofauna from the isolated highlands of northeastern Nicaragua, which is
characterized by a high proportion of endemic species. Two other clusters are evident
when analyzing the herpetofaunal similarities among Nicaragua, the Pacific versant and
the central mountains and the Atlantic lowlands. In addition, the Pacific lowlands are
characterized by a relatively homogeneous composition of the herpetofauna. In contrast,
many species have their northern limit of distribution in the Atlantic lowlands with the
ranges of most of these species ending in southern Nicaragua. The central mountains
constitute the southern limit of distribution of several highland species. In general, there
is a greater contribution of reptile than amphibian species to the total herpetofauna
present in each forest formation. This unbalance is slightly higher in the dry than in the
moist parts of the country. The similarities in the composition of the reptiles between the
different forests formations seem to be relatively distinct on an elevation factor, whereas
in amphibians similarities might be better explained in correlation with humidity. The
total amount of amphibian and reptile species in Nicaragua has a Middle American
Element dominance and varies b