Desmognathus comprises 21 currently recognized species of salamanders in eastern North America. Assemblages of 3–6 species occur in the Appalachian Mountains, wherein the larger species are more aquatic and the smaller more terrestrial. Adaptive divergence along the habitat gradient from stream to forest involves variation in such life-history traits as age and size at metamorphosis and maturation, survival, propagule size, and fecundity. In this study I examined the tradeoff between egg size and clutch size in North Carolina populations of D. santeetlah, D. ocoee, and D. aeneus, with special emphasis on the latter two species. Traits evaluated included standard length, body mass, trunk volume, egg size, clutch size, and clutch volume. For D. aeneus and D. ocoee, regressions of log-transformed values of body mass and trunk volume on standard length, and trunk volume on body mass, indicated strong similarity between the species in those body proportions that ostensibly constrain female reproductive effort. In all three species bivariate linear regressions of log-transformed values of clutch dimensions on body size suggested little correlation between egg size and body size within species, although larger species had larger eggs, larger clutches, and greater clutch volumes. An apparent interspecific tradeoff between egg size and clutch size in D. aeneus and D. ocoee suggested a common pattern in the relationship between body size and reproductive effort in these species. The results provided further evidence of a high level of life-history invariance in the genus Desmognathus, embodied in tradeoffs, which may stem from morphological conservatism related to specializations of the musculo-skeletal system.
Understanding the spatial ecology and foraging strategy of invasive animals is essential for success in control or eradication. We studied movements and activity in juvenile Brown Treesnakes on Guam, as this population segment has proven particularly difficult to control. Distance between daytime refugia (from telemetry of 18 juveniles, 423–800 mm snout–vent length) ranged from 0–118 m (n = 86), with a grand mean of 43 m. There were tendencies for shorter snake movements on nights directly following a full moon and on dry nights, but variation among snakes was of a larger magnitude and would greatly reduce chances to detect moon or rain effects unless corrected for. Snake activity was estimated from audio recordings of signals from “tipping” radio transmitters, analyzed for pulse period and amplitude. Activity was highest in the hours immediately after sunset, and gradually declined throughout the night before dropping abruptly in conjunction with sunrise. Snake activity was higher on rainy nights, and tended to be highest during waning moons and when the moon was below the horizon. We conclude that small Brown Treesnakes forage actively and appear to move far enough to regularly encounter the traps and bait used on Guam for control purposes, suggesting that alternative explanations are required for their low capture rates with these control tools.
Reproductive success is often difficult to ascertain in reptiles because of inconspicuous reproductive behaviors such as courtship that occurs in aquatic habitats and cryptic breeding outcomes such as multiple paternity and sperm storage. We corroborated field observations of mating behavior with genetic parentage analysis to assess the mating system and reproductive success in the rare Blanding's Turtle (Emydoidea blandingii) within a fragmented landscape in Will County, Illinois. During four consecutive years of radio-telemetry monitoring, we observed promiscuous mating behavior among males and females. Parentage was strongly skewed (one male sired 38% of 272 offspring) and multiple paternity was rare (11% of 28 clutches). Both males and females produced offspring with multiple individuals over the course of the study, but parentage did not always correspond with observed mating attempts; only 41% of male mating attempts observed in the field corresponded with sired offspring. For males, number of female mates inferred from paternity analysis was positively correlated with total number of offspring sired. No correlation was found between relatedness of observed mating pairs and hatching success. Repeat paternities in clutches were detected among years, with one confirmed instance of across-season sperm storage. High variation in reproductive success and low levels of multiple paternity in Blanding's Turtle in Will County compared to other areas may be attributed to habitat modification, small population size, and disruption of the mating system.
Sexual size dimorphisms are common in many species of anurans, and have often been ascribed to different selective forces that influence reproductive success in males and females. However, less is known about dimorphisms in whole-organism physiology or in internal morphology in anurans. In this study, we investigated potential differences in metabolism, visceral organ mass, and stored energy content between male and female American Toads (Anaxyrus americanus) collected en route to breeding areas during the spring. Female toads were both longer and more massive than males. Males demonstrated larger increases in metabolic rate, heart mass, liver mass, and nonpolar lipid content with increasing body size than did females, but kidney mass did not differ between the sexes. The ovaries of the females represented, on average, 38% of the total dry mass and 54% of the total caloric energy contained in their bodies. However, the body-size adjusted caloric content of the carcass did not differ between males and females. Our findings suggest that larger males are physiologically able to support greater levels of activity during the breeding season and thus will more likely engage in more strenuous activities such as calling, active seeking of females, and amplexus interference, compared to smaller males. Large females, on the other hand, appear to preferentially allocate resources to oogenesis. In addition, our findings suggest that although the overall energetic cost of reproduction may be greater for females, there may be other energetic constraints within or outside of the reproductive period that limit the ability of males to allocate resources to growth and storage.
Loss of biodiversity within relatively pristine protected areas presents a major challenge for conservation. At La Selva Biological Station in the lowlands of Costa Rica, amphibians, reptiles, and understory birds have all declined over the past four decades, yet the factors contributing to these declines remain unclear. Here, we conduct two tests of the hypothesis that faunal declines are linked to shifting dynamics of leaf litter, a critical microhabitat for amphibians and reptiles and a major component of forest carbon cycles. First, we conduct a 16-month manipulation of leaf litter and measure response by terrestrial amphibians and reptiles. Second, we synthesize three year-long datasets collected over four decades to evaluate potential multi-decade change in standing litter depth. We show that litter depth regulates density of amphibians and reptiles, and that the strongest response to manipulations is in species that decline most rapidly based on long-term data. Our synthesis of litter depth data suggests considerable interannual variability in standing stocks of leaf litter with lowest quantity of leaf litter in the most recent sampling period. These tests are consistent with the hypothesis that these faunal declines may be in part driven by changes in forest litter dynamics, and ultimately to climate-sensitive carbon cycles.
The tuvirão (Gymnotus inaequilabiatus) attains the largest body size (c. 1 m) of any species within Gymnotus, and the type specimen is the largest known specimen of the genus. Gymnotus inaequilabiatus is one of several species in Gymnotus that often have been misidentified or mistaken for one another, in part because of their similar external appearance and their overlapping geographic ranges in southern Brazil and northern Argentina. Here we redescribe G. inaequilabiatus using conventional osteological and morphological tools, and also High Resolution X-Ray Computed Tomography of the 184-year-old type specimen of the species. We report characters showing that this species is a member of the G. tigre species group, rather than the G. carapo species complex, as had previously been believed. We also provide a detailed description of the cranial osteology of the large-bodied type specimen, which represents the greatest extent of hypermorphosis known in the Gymnotus. O tuvirão (Gymnotus inaequilabiatus) é a maior espécie de Gymnotus (c. 1 m) e seu espécime tipo é um dos maiores espécimens conhecidos deste grupo. Gymnotus inaequilabiatus é uma das espécies deste gênero erroneamente identificada e confundida com outro congênere que possue uma distribuição similar no sul do Brasil e nordeste da Argentina. Nesse trabalho nos redescrevemos G. inaequilabiatus baseando-se em osteologia convencional e a tomografia computadorizada de alta resolução do espécime tipo. Demonstra-se que esta espécie faz parte do grupo de espécies G. tigre e não parte do complexo de espécies do grupo G. carapo como previamente proposto. Uma detalhada descrição osteológica do crânio do espécime tipo é fornecida, e este representa o extremo máximo de hipermorfose no gênero.
Here we present a re-description of Abudefduf luridus and reassign it to the genus Similiparma. We supplement traditional diagnoses and descriptions of this species with quantitative anatomical data collected from a family-wide geometric morphometric analysis of head morphology (44 species representing all 30 damselfish genera) and data from cranial micro-CT scans of fishes in the genus Similiparma. The use of geometric morphometric analyses (and other methods of shape analysis) permits detailed comparisons between the morphology of specific taxa and the anatomical diversity that has arisen in an entire lineage. This provides a particularly useful supplement to traditional description methods and we recommend the use of such techniques by systematists. Similiparma and its close relatives constitute a branch of the damselfish phylogenetic tree that predominantly inhabits rocky reefs in the Atlantic and Eastern Pacific, as opposed to the more commonly studied damselfishes that constitute a large portion of the ichthyofauna on all coral-reef communities.
Polymorphic species provide an opportunity to examine the process of sympatric divergence as it occurs. The Eastern Red-backed Salamander, Plethodon cinereus, is a polymorphic species that has served as a model organism in behavioral and ecological studies. Recent work suggests that the two most common color phenotypes (striped and unstriped) exhibit weak assortative mating and are diverging along a number of niche dimensions including temperature optima, diet, and response to predators. Males and females of P. cinereus are territorial and this behavior is thought to function in the context of prey and mate acquisition. Striped males have been shown to gain access to larger, and presumably more fecund, females. We posited that this pattern emerges through differential territorial behavior between the two phenotypes. We predicted that striped and unstriped salamanders would differ in their use of cover objects in the field, and in their aggressive responses to intruders in the laboratory. We examined salamander cover use and movement by placing artificial cover objects (ACOs) on the forest floor and monitoring them for 3.5 years. We compared residency time, number of recaptures, and number of ACOs occupied between the two phenotypes. The proportion of striped salamanders that were territorial residents was significantly greater than the proportion of unstriped salamanders that were territorial residents. Striped salamanders also exhibited significantly longer territorial residency, were recaptured more often, and were more often found under multiple, adjacent cover objects than unstriped salamanders. In the laboratory, we examined territorial behavior of the two morphs. As residents, striped salamanders were more aggressive and less submissive than were unstriped residents. When compared to intruders, resident salamanders of both morphs behaved more aggressively, but significant differences between resident and intruder behavior were only detected for the striped phenotype. These differences in aggression and cover object use may help to explain how striped males gain access to larger females and may be important in the interpretation of sympatric niche divergence and assortative mating by color in this species.
Based on previous literature, male salamanders of the genus Eurycea possess sperm transport ducts that are homogenous (in terms of histology) along their entire length; i.e., a transverse tubule. Considering this structural homogeneity is unique among salamanders, this feature could potentially be a synapomorphy for Spelerpinae. We tested this hypothesis by re-evaluating the histology of the sperm transport ducts of multiple members of Spelerpinae (Eurycea longicauda, E. lucifuga, and E. multiplicata) and compared our results with representatives from all subfamilies of Plethodontidae (Bolitoglossinae, Hemidactylinae, and Plethodontinae). We reject the findings of previous work that spelerpine salamanders possess homogenous sperm transport ducts along their entire length. Discrete regions are present along the sperm transport ducts of Spelerpinae that include, from proximal to distal, a vas efferens, genital kidney proximal tubule, genital kidney distal tubule, and genital kidney collecting tubule. A distinct renal corpuscle often exists between the communication of the vas efferens and genital kidney proximal tubule. This regionality is not only stereotypical for the sperm transport ducts in all plethodontid salamanders, but also for salamanders in general. Similar to other lineages of salamanders (i.e., Rhyacotritonidae and Sirenidae), all plethodontid salamanders examined lack a longitudinal collecting duct and distinct neck and intermediate segments. We found no characteristic that could potentially serve as a non-ambiguous synapomorphy for Spelerpinae or Plethodontidae with use of sperm transport duct histology. However, it appears that the Bolitoglossinae, Hemidactylinae, and Spelerpinae often lack arteriole connection to their glomeruli within the genital kidney renal corpuscles, yet this trait is ambiguous within taxa of these subfamilies.
The Spotted Eagle Ray, Aetobatus narinari, is a semi-pelagic myliobatoid recognized as near threatened by the World Conservation Union. A decreasing population trend, K-selected life history, and primarily inshore, coastal habitat renders this species susceptible to over-exploitation by targeted fisheries, drift netting, and capture as bycatch. Recent molecular investigations and subsequent taxonomic recognition as a species complex have left a large deficiency in current knowledge of A. narinari and a complete absence of data concerning population structure and genetic health for the northwestern Atlantic Ocean. Our study is the first to examine fine-scale structure on a regional basis in the Gulf of Mexico and coastal Atlantic waters off the United States. Individuals sampled non-invasively from four sites, Sarasota, FL (n = 143), the Everglades, FL (n = 36), Ft. Pierce, FL (n = 8), and the southeastern U.S. Atlantic coast (n = 24), were genotyped across eight microsatellite loci. Standard tests for Hardy-Weinberg equilibrium, null alleles, linkage disequilibrium, allelic richness (mean = 15.38), and gene diversity (0.701) were performed. Analyses of statistically significant patterns of geographic structure using STRUCTURE and AMOVA procedures yielded non-significant findings and support a single population model. Effective population size was estimated between 2,200 and 3,300 (LDNe and ONeSAMP, respectively). Assessments of structure and genetic health for the northwestern Atlantic are critical to furthering our understanding of viability of A. narinari.
Variation at two mitochondrial DNA regions was used to assess the phylogeographic history of the American brook lamprey, Lethenteron appendix, a widespread and typically non-parasitic species in eastern North America. Little differentiation (<0.2%) was observed among populations throughout its range. Specimens of putatively parasitic individuals had sequences identical to non-parasitic individuals. Additional sequences from other members of the genus Lethenteron also demonstrated little or no differentiation with American brook lamprey (<1.2%). These results support the hypothesis of a recent range expansion of the American brook lamprey. Further, the absence of variation among several of the species of Lethenteron suggests a recent origin of multiple non-parasitic species with insufficient time for lineage sorting or ongoing gene flow among populations of a trophically polymorphic species. This study calls into question the current species diversity of Lethenteron.
Subspecies have most often been described qualitatively with small sample sizes as excerpted from geographic continua. They present a long-standing conflict with evolutionary and statistical principles as well as conservation planning that often relies upon a phylogenetic perspective. Herpetological subspecies have been recognized in the literature as exceeding numerical expectations and subsequent reevaluations during the last decade have decreased their numbers ∼50%, the exception being whiptail lizards (Aspidoscelis, family Teiidae). Here we used 842 base pairs of mitochondrial (mt) DNA to examine potential taxonomic and conservation boundaries among two putative species and four subspecies of the abundantly polytypic Aspidoscelis inornata (Little Striped Whiptail Complex, LSWC) of southwestern North America. Body coloration, but not mtDNA, distinguished two putative species inhabiting alkali deposits, whereas neither dataset could diagnose three paraphyletic subspecies. A trend to elevate putative subspecies following a more contemporary evaluation is premature for the LSWC: we suggest that two species (arizonae, pai) and three subspecies (gypsi, junipera, llanuras) lack molecular and morphological differentiation and thus should be rescinded in taxonomic rank. These uncertainties concerning the LSWC with regard to its distributions and relationships impinge upon conservation proposals that, for example, seek to list A. arizonae as ‘threatened’ under the Endangered Species Act. Frecuentemente las subespecies han sido descritas cualitativamente y con tamaños de muestra pequeños extraídos de un continum geográfico. Ellas representan un viejo conflicto con los principios evolutivos y estadísticos así como para desarrollar planes de conservación que frecuentemente dependen de una perspectiva filogenética. Las subespecies herpetológicas han sido reconocidas en la literatura como excediendo las expectativas numéricas y una reevaluación subsecuente durante la década pasada ha disminuido sus números en ∼50%, siendo la excepción los Huicos (Aspidoscelis, familia Teiidae). Aquí utilizamos 842 pares de ADN mitocondrial (mt) para examinar el potencial taxonómico y límites de conservación entre dos supuestas especies y cuatro subespecies de la abundante y politípica Aspidoscelis inornata (complejo del Huico Liso, CDHL) del suroeste de Norteamérica. El patrón de coloración, pero no el ADN mitocondrial, distingue a dos supuestas especies que habitan en los depósitos de álcali mientras que ningún conjunto de datos pudo diferenciar las tres subespecies parafiléticas. Elevar a estas supuestas subespecies siguiendo una evaluación más contemporánea es prematuro para CDHL: sugerimos que las dos especies (arizonae y pai) y las tres subespecies (gypsi, junipera, llanuras) carecen de diferenciación morfológica y molecular por lo que deben ser consideradas sin rango taxonómico. Esta incertidumbre con respecto a las CDHL en cuanto a sus relaciones y distribuciones impacta propuestas de conservación que, por ejemplo, buscan enlistar a A. arizonae como “amenazada” bajo la ley de especies en peligro de extinción.
Eptatretus aceroi, new species, is described from one specimen captured on the upper continental slope in Colombian Caribbean waters at 705 m depth. The species can be distinguished from all congeners by having five gill apertures, 3/2 multicuspid teeth in the outer and inner tooth rows, respectively, an extremely slender body with the depth at the vertical through the pharyngocutaneous aperture 2.4% of the total length, and by having a total of 174 slime pores, the highest count in the genus. The species is compared with the other western Atlantic five-gilled species of Eptatretus. Se describe a Eptatretus aceroi a partir de un espécimen capturado en el talud continental superior del Caribe colombiano a 705 m de profundidad. La especie se distingue de todos sus congéneres por poseer cinco aberturas branquiales, un patrón dental de 3/2 dientes multicúspidos en la hilera externa e interna respectivamente, un cuerpo extremadamente delgado, con un profundidad del cuerpo a nivel del ducto faringocutáneo de 2.4% de la talla total, y por tener un conteo total de poros de 174, el mayor conteo en el género. La especie se compara con otras especies de Eptatretus del Atlántico occidental que presentan cinco aberturas branquiales.
A new genus and species of the frogfish family Antennariidae, subfamily Histiophryninae, is described on the basis of three specimens collected near Kurnell and Bare Island in Botany Bay, New South Wales, Australia. It differs from all other antennariid genera in having a combination of features that includes a unique morphology of the first and second dorsal-fin spines, some or all fins fringed with red, and a unique combination of fin-ray and vertebral counts. The new genus is diagnosed, described, and compared to its sister genus, Kuiterichthys, using both molecular and morphological data. Notes on habitat and sponge mimicry, locomotion and defense, and reproduction and parental care are also provided as well as a diagnosis and a revised key to the known genera of the Histiophryninae.
Phylogenetic placement of most species of darters is reasonably well understood regarding their closest relatives. However, an exception is the apparently extinct Etheostoma sellare. In this paper, we included E. sellare in a phylogenetic analysis with 62 extant species representing one or more species from all previously recognized darter subgenera. The analysis included 77 new, or previously proposed, polarized, morphological characters for E. sellare and those characters plus reported molecular sequences (RAG1) for the extant species. A parsimony analysis of concatenated data for each species produced nodes congruent with the subgeneric taxonomy of darters and established unambiguous placement for the morphologically distinctive E. sellare placed in the newly created subgenus Mooreichthys to resolve a previous triotomy in which the single taxon was grouped with subgenera Poecilichthys and Litocara. Unique morphological or nucleotide synapomorphies support the monophyly of the subfamily Etheostomatinae and the most basal genus Percina sister to sister genera Ammocrypta and Etheostoma. Other unique synapomorphies support relationships within genus Percina, a close relationship of subgenus Allohistium to a clade containing subgenera Etheostoma + Ulocentra + Nanostoma, rather than to subgenus Nothonotus, and the monophyly of subgenus Catonotus. Relationships of some species, including sisters E. mariae and E. parvipinne, remain uncertain.
The extinction of Stomatepia mongo Trewavas, 1972, a cichlid species from the Barombi Mbo crater lake, Cameroon, has been repeatedly speculated. Here, we review over 180 presumably unpublished records of this species since its description. Because a majority of them originate from our extensive surveys in the last several years, it is evident that this species still persists. Nevertheless, it is still considered as the rarest species in the lake, but its relative abundance is probably comparable to that in 1972 when the species was originally described. The species also does not seem to live exclusively in deep waters as was previously hypothesized, because we repeatedly collected and/or observed it in the shallow waters as well. We also listed our notes on the species' coloration and behavior. Although we document the persistence of S. mongo, it remains threatened by the impact of intensive human activities (fishing and farming) in the area.
We describe Oryzias soerotoi, a new species of ricefish, from Lake Tiu, Central Sulawesi, Indonesia. The new species is distinguished from all other species in the genus Oryzias in Sulawesi by combination of brilliant orange coloration in the dorsal and ventral margins of the caudal fins of adult males, 30–32 scales along the lateral midline, 9–10 pectoral-fin rays, head lengths of 21.9–24.9% SL, anal-fin base lengths of 23.7–29.7% SL, and maximum SL up to 32.1 mm. The orange margins of the caudal fins of males become more brilliant during courtship. Kami mendiskripsi Oryzias soerotoi, satu jenis baru ikan padi dari Danau Tiu, Sulawesi Tengah, Indonesia. Jenis baru ini dengan mudah dapat dibedakan dari semua jenis anggota genus Oryzias di Sulawesi dengan adanya kombinasi warna jingga yang sangat mencolok di bagian atas dan bawah sirip ekor pada jantan dewasa, 30–32 jumlah sisik sepanjang garis sisi, 9–10 jumlah jari-jari sirip dada, ukuran kepala pendek 21.9–24.9% SL, panjang pada pangkal sirip anal 23.7–29.7% SL, dan maksimal SL mencapai 32.1 mm. Warna jingga di sirip ekor pada jantan menjadi lebih mencolok selama proses percumbuan.
To determine the valid name of the Borneo eel that has a plain body coloration and is endemic to Borneo Island, three type specimens of Anguilla borneensis Popta, 1924, Anguilla malgumora Kaup, 1856, and Muraena malgumora Bleeker, 1864 were examined and compared to the morphological characters of the 42 longfin eels from Borneo, A. anguilla (44), A. japonica (37), and A. dieffenbachii (14), all of which have the same external appearance of a long dorsal fin and plain body color, except for M. malgumora Bleeker, 1864, which has a short dorsal fin. Discriminant analysis using 13 proportional characters and the relationship among three vertebral characters clearly showed that the type specimen of Anguilla malgumora Kaup, 1856 upon which Bauchot et al. (1993) proposed the revival of that name to replace A. borneensis Popta, 1924, based on priority without examining the specimen, was in fact clearly not a specimen of the Borneo eel as was concluded by Ege (1939). Therefore A. borneensis Popta, 1924 is the valid name for the Borneo eel, and A. malgumora Kaup, 1856 appears to be a junior synonym of A. anguilla (Linnaeus, 1758), and M. malgumora Bleeker is a junior synonym of A. bicolor McClelland, 1844.
Whereas, the vastly increased use of rotenone and other poisons in controlling fish populations, in more and larger bodies of water (including even whole stream systems), that has threatened the continued existence of certain local populations and even some local forms of native fishes, Be it therefore resolved, by the American Society of Ichthyologists and Herpetologists [ASIH], at its fortieth annual meeting, that federal, state, and other authorities, in planning and executing such control measures, be urged to seek in advance the advice of independent zoologists, and to use full caution and restraint, to the end that such populations and
THE Herpetologists' League is pleased to announce competitive grants for graduate student research for 2015. These awards are named in honor of the late Ernest E. Williams, the first Distinguished Herpetologist of The Herpetologists' League. An award ($1000.00 maximum amount) will be presented to one winner in each category: Behavior Conservation Ecology Physiology Morphology/Systematics The application form and rules are also available on the HL website at http://www.herpetologistsleague.org/dox/eewilliamsgrant.pdf. Entries must be received by 5:00 PM central time on 15 December 2014. Send complete application (cover page,THE HERPETOLOGISTS' LEAGUE EE WILLIAMS RESEARCH GRANT
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