In an effort to identify long-term changes in a river turtle community and its habitat, we reexamined the turtle community in a 4.6 km section of the North Fork of White River (NFWR), Ozark County, Missouri, that was previously studied between 1969 and 1980. We compared data collected in 2004 to data from 1969 and 1980 to determine if alterations in the habitat, community composition, or Northern Map Turtle (Graptemys geographica) population size and structure had occurred. Previous studies showed that the population of G. geographica declined between 1969 and 1980. Our results indicate that the population of G. geographica failed to rebound by 2004. The population of Red-eared Sliders (Trachemys scripta elegans) that established in the research section between 1971 and 1980 expanded their distribution between 1980 and 2004. Threats to the population of G. geographica included lack of basking sites, increased human recreational use of the stream, and water quality degradation.

We investigated the effects of riparian zones, and associated environmental variables, on the composition and number of species of frogs per sample unit in an Amazonian forest. Sample plots in riparian (up to 10 m from water bodies) and non-riparian areas were distributed over a 25 km² sampling grid to obtain a representative sample of habitats in each category. Each plot was sampled three times, over two rainy seasons. The riparian plots harbored more and different species than the non-riparian plots. In riparian areas near streams, the species composition changed along the gradient associated with stream width. The higher number of individuals and species in riparian plots highlights the importance of water courses and associated riparian areas for the conservation of anuran diversity in Amazon rainforests.

In mouth-brooding fishes, there may be a trade-off between respiratory function (gill size and shape) and reproduction (space in the buccal cavity for offspring) during periods of parental care. This trade-off may become particularly apparent under low-oxygen conditions if a mouthful of eggs compromises respiratory pumping. In this study, we compare gill size and position among five males, ten brooding females, and eight non-brooding females of the African cichlid, Pseudocrenilabrus multicolor victoriae collected from a hypoxic swamp in Uganda. Brooding females exhibited a smaller total and average gill filament length than non-brooding females and males and a more elongated arch that may relate to spatial constraints imposed by the young. Importantly, brooding females also exhibited smaller overall hemibranch surface area than non-brooding females and males. In conjunction with earlier studies on this species that have reported a higher metabolic rate, higher aquatic surface respiration thresholds, and deeper ventilations in brooders, we suggest that the smaller gill size in brooders may reflect spatial accommodation and reduced respiratory function associated with parental care.

Despite monogamous mating systems and size-assortative mating observed in many seahorse (Hippocampus) species, sexual dimorphism is nonetheless observed in some. This study documents morphometry and allometry of the adult Lined Seahorse, Hippocampus erectus, and examines sexual dimorphism in these measures. Males exhibit longer standard lengths, shorter trunks with isometric growth, and longer tails with positively allometric growth. In contrast, females demonstrate positively allometric growth of trunk length and isometric growth in tail length. There is no observed dimorphism in the weight–length relationship, but it is positively allometric. Sexual dimorphism of body parts suggests sexually selective pressures, with longer trunks in larger females accommodating developing ovaries, and longer tails hypothetically garnering advantages for larger males in courtship behavior (tail grabbing), gestation (supporting brood pouches), and intraspecific competition (tail wrestling). Though monogamous mating systems predict sexual monomorphism, the dimorphisms observed are probably a result of selection pressures due to the conventional sex roles maintained in this species.

Barbeled dragonfishes (Stomiidae) comprise about 281 species in 27 genera, most of them highly specialized mesopelagic predators. Fusion of pharyngobranchials three and four has been reported in several genera, but without supporting ontogenetic evidence. We studied cleared and double stained ontogenetic series of species in 22 of the 27 recognized stomiid genera and found that the third and fourth pharyngobranchials fuse ontogenetically in 17 genera. In contrast, in four genera (Neonesthes, Borostomias, Rhadinesthes, and Stomias), the fourth pharyngobranchial cartilage remains separate from the third in adults, as it generally does in teleosts. One genus, Astronesthes, shows an intermediate state in which these two elements fuse only partially. Additionally, our data indicate that the posteriormost upper pharyngeal toothplate in stomiids is the fourth (UP4) rather than the fifth (UP5), as previously proposed. The fourth upper pharyngeal toothplate is closely associated with the ventral surface of the fourth pharyngobranchial cartilage during early larval ontogeny. Therewith, we address a long-standing homology problem regarding the identity of UP4 and UP5 among basal neoteleosts and our results are discussed comparatively.

It is broadly accepted that snakes are able to regulate their body temperature (T_b) behaviorally, but fundamental differences in this ability have been suggested to exist between temperate and tropical species. Herein, we examined the thermal ecology of the Golden Lancehead, Bothrops insularis, a critically endangered Neotropical crotaline snake endemic to Queimada Grande Island (QGI), southeastern Brazil. We sampled T_b's of individual snakes found in the field and tested which proximal factors, biotic and abiotic, were potentially relevant for their thermoregulatory behavior and T_b selection. We verified whether T_b regulation would be compensated, through the day and/or seasons, by adjustments in the thermoregulatory effort. Finally, we hypothesized that for a Neotropical snake, the thermoregulatory effort would be lower because the thermal quality of habitat is higher compared to species inhabiting temperate zones. In general, B. insularis conformed to this hypothesis. However, seasonal declines in the thermal quality of habitat during the colder seasons and during nighttime were compensated by increases in the effectiveness of thermoregulation. Overall, T_b of B. insularis is determined largely by environmental variables, particularly air temperature, with some influence of biotic factors, such as body size. Use of open areas for basking, a common thermoregulatory behavior for squamates, was largely avoided; this may be explained by ecological factors, and may be due to foraging constraints and increased risks of predation and dehydration.

Stomach contents analysis (SCA) provides a snap-shot observation of a consumer's diet. Interpretation of SCA data can be complicated by many factors, including variation in gastric residence times and digestion rates among prey taxa. Although some SCA methods are reported to efficiently remove all stomach contents, the effectiveness of these techniques has rarely been tested for large irregular shaped prey with hard exoskeletons. We used a controlled feeding trial to estimate gastric residency time and decomposition rate of a large crustacean prey item, the Blue Crab (Callinectes sapidus), which is consumed by American Alligators (Alligator mississippiensis), an abundant apex predator in coastal habitats of the southeastern United States. The decomposition rate of C. sapidus in the stomachs of A. mississippiensis followed a predictable pattern, and some crab pieces remained in stomachs for at least 14 days. We also found that certain portions of C. sapidus were prone to becoming caught within the stomach or esophagus, meaning not all crab parts are consistently recovered using gastric lavage techniques. However, because the state of decomposition of crabs was predictable, it is possible to estimate time since consumption for crabs recovered from wild alligators. This information, coupled with a detailed understanding of crab distributions and alligator movement tactics could help elucidate patterns of cross-ecosystem foraging by the American Alligator in coastal habitats.

Juvenile amphibians are capable of long-distance upland movements, yet cues used for orientation during upland movements are poorly understood. We used newly metamorphosed Wood Frogs (Lithobates sylvaticus) to investigate: (1) the existence of innate (i.e., inherited) directionality, and (2) the use of olfactory cues, specifically forested wetland and natal pond cues during emigration. In a circular arena experiment, animals with assumed innate directionality did not orient in the expected direction (suggested by previous studies) when deprived of visual and olfactory cues. This suggests that juvenile Wood Frogs most likely rely on proximate cues for orientation. Animals reared in semi-natural conditions (1500 l cattle tanks) showed a strong avoidance of forested wetland cues in two different experimental settings, although they had not been previously exposed to such cues. This finding is contrary to known habitat use by adult Wood Frogs during summer. Juvenile Wood Frogs were indifferent to the chemical signature of natal pond (cattle tank) water. Our findings suggest that management strategies for forest amphibians should consider key habitat features that potentially influence the orientation of juveniles during emigration movements, as well as adult behavior.

The Barrens Darter (Etheostoma forbesi) is a rare darter in subgenus Catonotus endemic to the Caney Fork River system in middle Tennessee. Hybridization with the closely related Fringed Darter (E. crossopterum) has been assumed as a risk to E. forbesi. To assess chronology and similarity of nesting habitat between these species, nests of both egg-clustering darters were observed through the spring nesting seasons in four streams during 2008 and 2009. Microhabitat variables associated with nests exhibited evidence of headwater specialization by E. forbesi that may isolate spawning populations from E. crossopterum. Etheostoma forbesi used nest rocks of smaller average dimensions and bottom surface area, and nested at shallower depths where water velocities were higher than nesting individuals of E. crossopterum. Nesting chronology and clutch sizes were similar between species, with spawning periods similar to those reported for other darter species in subgenus Catonotus and with clutch sizes up to 2,000 eggs/nest. Nests were present from March through early June at Duke, Lewis, and Meadow Branch creeks, but spawning was delayed by approximately two weeks at West Fork Hickory Creek, the largest and only spring-fed stream in the study. Etheostoma forbesi displayed peak egg production from mid-April to early May in Duke and Lewis creeks. Etheostoma crossopterum in a similar-sized stream also followed this chronological pattern, but spawning of E. crossopterum was delayed and the active nesting period was protracted into mid-June in the largest and spring-fed stream. Under contempory streamflow conditions, the observed differences in spawning microhabitat suggest a low likelihood of interspecific hybridization, despite the similarities in timing of the two species' spawning activities.

Movements are risky behaviors to animals, and amphibians are no exception, yet most species of amphibians exhibit cyclic annual movements. Crawfish Frogs (Lithobates areolatus) are a relatively understudied species of North American amphibian considered to be “Near Threatened” globally. To better understand the biology of this species, and in particular to assess the role that movements play in affecting survivorship, we radio tracked 48 Crawfish Frog adults in 2009–2010. Our study encompassed a total of 7,898 telemetered-frog days; individual frogs were tracked for up to 606 days. These data demonstrate two behaviors previously undocumented in this species: 1) migration distances that averaged nearly 0.5 km, and for one frog was approximately 1.2 km; and 2) philopatry to upland burrows excavated by crayfish. Together, these findings indicate that Crawfish Frogs have a remarkable ability to home to distant upland burrow sites. Burrow fidelity in Crawfish Frogs involves, in part, following similar migration routes to and from breeding wetlands. Burrow fidelity also occurs after ranging movements, and again often involves individual frogs following the same circuit across years. We demonstrate that movements are hazardous for Crawfish Frogs (about 12 times riskier than burrow dwelling), and therefore have survival consequences. Our data further suggest that adult Crawfish Frogs are not typically moving long distances from one upland burrow to another to populate new sites; instead two mechanisms—adults varying breeding wetlands across years and juvenile dispersion—are primarily responsible for the colonization of new habitats.

Fundulus jenkinsi is recognized federally and within a number of northern Gulf of Mexico states as a Species of Concern. Little is known about its life history, but a detailed reproductive histology study of F. jenkinsi can provide the foundation needed to quantify reproductive parameters in this rare species in need of conservation. Monthly gonadosomatic index (GSI) of male and female F. jenkinsi indicated a spawning season from April through August. However, ovarian histological analysis suggested March through August was a more accurate spawning season. The multiple oocyte stages within F. jenkinsi in the spawning capable reproductive phase indicates batch spawning, similar to other members of its family. Many estuarine members of the family Fundulidae exhibit a semilunar spawning pattern, yet the oocyte composition of ovaries of F. jenkinsi suggested spawns occur multiple days around the time of spring tides both within a population and on the individual level. Spawning did not occur on neap tides, and no late secondary growth vitellogenic oocytes (SGl) were found in the majority of females captured during neap tide. The lack of SGl oocytes in females during the spawning season suggests the necessity for establishing a new sub-phase within the spawning capable phase, termed the redeveloping sub-phase. This new sub-phase is applicable to other batch spawning species with group synchronous oocyte development. This work contributes to a better understanding of the importance of intertidal saltmarsh habitat to F. jenkinsi, as spawning intensity appears to increase with tidal height and marsh inundation.

We used radio-telemetry to identify diel activity patterns in the Eastern Kingsnake, Lampropeltis getula getula in Southwestern Georgia. We monitored tagged snakes at four time periods within a 24-hour cycle (0800–1359 h, 1400–1959 h, 2000–0159 h, and 0200–0759 h) in spring, summer, and fall (March–November), which comprise the annual activity period for Eastern Kingsnakes in this region. We used a logistic regression approach to identify specific environmental factors that best predicted Eastern Kingsnake movement. We found Eastern Kingsnakes were primarily active during the day (χ²  =  34.10, P < 0.001, n  =  452) in the spring (χ²  =  6.25, P < 0.04, n  =  474) and activity was best predicted by air temperature, soil temperature, relative humidity, and light intensity. Our observations differed from anecdotal descriptions of nocturnal activity and seasonal shifts in diel activity patterns in Eastern Kingsnakes.

Variation in individual activity budgets may have important impacts for the long-term fitness of a population, yet our understanding of the factors shaping activity remains limited. Here, we report on intraspecific activity budget variation and the factors influencing it within a population of emerald basilisk (Basiliscus plumifrons) lizards in Costa Rica. Because behavioral variation may have a seasonal component, we monitor activity across both a wet and dry season. All basilisks exhibited similar frequencies of behavior throughout the day, with the exception of foraging rate. Adult females foraged more often than adult males or juveniles, possibly to satisfy higher expected energetic demands during the reproductive season. Juvenile and adult lizards occupied separate habitats characterized by significant differences in vegetation structure. In particular, juvenile lizards were more frequently observed in open, grassier habitats that were closer to water than adults. Juveniles may reduce their chances of predation by or competition with larger individuals in these areas, or may simply frequent those areas to take advantage of the size-dependent water-running ability characteristic of this species. As the area shifted from a wet to a dry period, juvenile activity significantly declined and by the end of the study very few juveniles were encountered. Adult lizards did not exhibit reduced activity per se, but instead shifted the timing of peak activity into early-morning and late-afternoon periods. Although activity budgets were largely similar among juveniles and adults, our findings highlight both ontogenetic variation in habitat use and the influence of seasonal variation on basilisk activity.

Most snakes have the chemosensory ability to identify chemical cues from conspecifics, which is useful in many social and sexual behaviors. This has been especially well studied in European and North American snake species. In contrast, there is a general lack of knowledge on the biology and especially on the use of chemical signals by most Neotropical snake species. Here, we explored the existence of intraspecific recognition by chemical cues in several snake species from Ecuador within the families Boidae (Boa constrictor constrictor, Boa constrictor imperator, Corallus hortulanus, and Epicrates cenchria) and Colubridae (Lampropeltis triangulum micropholis) by using experiments of tongue-flicking discrimination. Results showed that individuals of all species tested showed higher chemosensory responses to odors from conspecific individuals when compared to odors from individuals of other species, suggesting intraspecific chemosensory recognition in these snake species. In contrast, there was not chemosensory recognition between the two subspecies of B. constrictor. We show that some Neotropical snake species are able to use chemical cues of conspecifics in intraspecific recognition, but further studies are needed to analyze the role of chemical signals in their biology and social behavior.

A new species of Bathyaethiops is described from the Lékoumou River in the Kouilou–Nairi basin of the Republic of Congo. Bathyaethiops atercrinis, new species, is distinguished from its three central African congeners in the possession of 21–24 scales in longitudinal series vs. 28–42 scales, and from Brachypetersius altus by the possession of a short, abridged lateral line consisting of only six or seven pored scales vs. a complete lateral line of 20–28 pored scales. The species is unique among congeners and related taxa in displaying marked sexual dichromatism and dimorphism of the supporting skeleton of the anal fin. The presence of B. atercrinis in the Lékoumou represents the first record of the genus in the Lower Guinean ichthyofaunal province and the first occurrence outside of the Congo basin.

Panturichthys fowleri (Ben-Tuvia, 1953) is redescribed on the basis of 27 specimens from the coasts of Israel, Lebanon, and Turkey. The species is recorded from Turkey for the first time. Morphological variation, especially in dentition and relative head–trunk length was found to be greater than previously recognized. The osteology is described from two cleared-and-stained specimens. A synopsis of the family Heterenchelyidae is presented, and a key to the known species is provided.

A new small Loricariidae, Hypostomus careopinnatus, is described from the Rio Taquari drainage, upper Rio Paraguay basin, Mato Grosso, Brazil. The new species can be easily distinguished from all congeners, except Hypostomus levis, by the absence of adipose fin. Hypostomus careopinnatus is distinguished from H. levis mainly by the presence of slender bifid teeth, with mesial cusp large and rounded, and lateral cusp small and pointed (vs. spoon-shaped teeth). The new species described herein completely lacks the adipose fin and also lacks the median pre-adipose plates in almost all specimens examined. The absence of adipose fin is probably an independent acquisition for Hypostomus careopinnatus and Hypostomus levis.

Astyanacinus yariguies, a new species, is described from Río Cascajales, Río Magdalena system, in the municipality of El Carmen, Santander, Colombia. This species is assigned to Astyanacinus because it exhibits all the diagnostic characters of the genus, including 25–36 branched anal-fin rays (28–30 in the new species), and a coloration pattern with two humeral spots, a midlateral stripe formed by anteriorly oriented chevron bars, and a horizontally oriented oval-shaped caudal spot that continues over the median caudal rays. Astyanacinus yariguies differs from its congeners by having 13 predorsal scales forming a regular series, six teeth in the maxilla, nine scale rows between the dorsal-fin origin and lateral line, and a relatively short snout length. This is the first report of the genus Astyanacinus from the Río Magdalena basin.

Physalaemus barrioi is a poorly known frog endemic to the highlands of Serra da Bocaina in the Atlantic Forest of southeastern Brazil. Herein, we redescribe the species based on the type series and new specimens collected at the type locality. We also present additional data on its vocalization, karyotype, and tadpole, including the external morphology, internal oral features, and chondrocranium. Physalaemus barrioi can be diagnosed by the following combination of characters: SVL in males larger than 24 mm; inguinal glands associated with dark ocelli; throat and vocal sac dark brown; and chest dark with small light blotches. Bioacoustical characteristics also distinguish P. barrioi from all other species of Physalaemus. The tadpole of P. barrioi is very similar to those of the P. gracilis group, from which it can be distinguished by several characteristics, including marginal papillae in a single row, absence of submarginal papillae, elliptical nares, and upper jaw sheath in a wide arch.

A new species of Pareiorhaphis is described from the Ribeirão Caraça, a tributary to the Rio Piracicaba, upper Rio Doce basin in the State of Minas Gerais, eastern Brazil. The new taxon is promptly diagnosed from all other species of Pareiorhaphis by having a unique color pattern in both sexes. The color pattern consists of conspicuous dark brown blotches irregularly scattered over a yellowish tan background on head, along the dorsal surface of body and flanks. In addition, the new species can be further distinguished from all congeners except P. eurycephalus, P. nudulus, and P. vestigipinnis, by the absence of an adipose fin. From those species it is distinguished by morphometric traits. The new species is further compared to P. nasuta and P. scutula, which also occur in the Rio Doce system.

The gobioid genus Trypauchenopsis and type species, T. intermedia, are redescribed based on examination of 485 specimens (including the holotype) from various localities in the Indo-West Pacific. The genus is unique in possessing forked middle radials of the ultimate dorsal- and anal-fin pterygiophores, no pleural ribs or only a single pleural rib on the ultimate precaudal vertebra, and caducous, cutaneous, short barbel-like processes scattered on the head. Two species that had been referred to the genus Taenioides (T. jacksoni and T. limicola) are now placed in the synonymy of Trypauchenopsis intermedia. Trypauchenopsis has often been confused with Taenioides or Brachyamblyopus; these three genera along with Gymnoamblyopus, Odontamblyopus, and Pseudotrypauchen are compared and characters to distinguish them are provided. The relationships of Trypauchenopsis to these genera are also discussed.

A new species of the genus Adontosternarchus (Gymnotiformes, Apteronotidae) is described from samples collected during high water periods in a relatively restricted area within the Rio Purus basin, Amazonas, Brazil. Adontosternarchus duartei differs from congeners in a series of details of pigmentation, meristics, and morphometrics and represents the sixth species in the genus. A key to the species of Adontosternarchus is provided.

A new species of American sole, captured in freshwater tributaries of the Río San Juan and Río Condoto, near Andagoya, Colombia, is described from four specimens collected by H. G. F. Spurrell around 1913. These fish were deposited in the fish collection of the British Museum (Natural History) and originally identified as Solea panamensis Steindachner, 1876. In the 1960s, Carl L. Hubbs and John A. Bollinger re-examined the specimens and determined that they represented an undescribed species, as indicated by labels placed in jars containing these specimens and through correspondence with staff at the British Museum. However, no formal description of this nominal species was published and its taxonomic status remained unclear. Our re-examination of these specimens and comparisons with all other described species of Trinectes support the conclusions of Hubbs and Bollinger that they are not Solea panamensis, now considered a junior subjective synonym of Trinectes fonsecensis (Günther, 1862), and that they represent an undescribed species. Formal description of the new species, Trinectes hubbsbollinger, named in recognition of the initial discoverers, is provided herein. Trinectes hubbsbollinger is distinguished from its congeners by the combination of 7–8 lightly pigmented, transverse chromatophore lines on the ocular side of the body, ocular-side lower lip with short fimbriae with few branches, few or no cirri on the scaleless area surrounding the ocular-side anterior naris, and absence of pectoral-fin rays.

Peckoltia is one of the 26 genera that constitute the Ancistrini. Although Peckoltia has been reviewed recently, its taxonomic status is not fully resolved and not easily distinguished from Hemiancistrus. Neither Peckoltia nor Hemiancistrus have any recognized synapomorphies supporting their monophyly. In this paper we describe a new species of Ancistrini from Rio Xingu drainage, Pará State, Brazil, and assign it to Peckoltia based on its deep body, presence of large odontodes on the cheeks, and lack of carenate plates on the body. The new species can be easily distinguished from all its congeners by its dorsal-fin color pattern (presence of dark thin stripes in the interradial membranes parallel to fin rays that fragment into small spots in larger specimens vs. bands, spots, dots, or membranes with a darker coloration in all other species). Peckoltia feldbergae, new species, differs from all its congeners except P. bachi, P. oligospila, and P. sabaji by having dark brown spots on the entire body (vs. presence of dark transversal bars on the body or a uniform color). Peckoltia feldbergae, new species, can be distinguished from P. oligospila and P. sabaji by a smaller postanal length (28.4–32.4% of SL vs. 34.3–38.8 and 35.7–41.0%, respectively). The description of this species is part of an effort to improve our knowledge about the remarkable diversity of rapids-dwelling loricariid catfishes that are greatly threatened by the construction of several large hydroelectric dams in Brazilian Amazon, and to provide a scientific name for a species exploited by the international aquarium fish trade.

Scinax alter, a taxon belonging to the S. ruber clade, has been previously suggested to represent a species complex. We analyzed variation among populations of Scinax alter using advertisement calls, dorsal color pattern, and external morphology. We identified three diagnosable groups distributed throughout the Atlantic Forest of eastern Brazil, which differ mainly in the advertisement call, dorsal drawing pattern, snout–vent length, and presence of tubercles on tarsus. Scinax alter was restricted to populations from south of Bahia State to Rio de Janeiro State, and two new species were related to the southern populations: Scinax imbegue, from Parque das Nascentes, Municipality of Blumenau (27°03′S, 49°05′W, 412 m a.s.l.), Santa Catarina State, Brazil, and Scinax tymbamirim, from Córrego Grande (27°35′S, 48°31′W, at sea level), Municipality of Florianópolis, Santa Catarina State, Brazil.

We screened 74 published microsatellite primers in Ambystoma annulatum, a species for which no microsatellite markers have been developed. Overall, we had a moderate success rate, identifying 11 polymorphic microsatellites previously developed in four different species of Ambystoma. We also conducted a review of the literature, collecting all published cross-species applications of microsatellite markers within the genus Ambystoma. From this, we identified 20 loci that have amplified in three or more species. Our synthesis of microsatellite use within the genus Ambystoma should prove valuable to future molecular research, especially in species without developed markers and for studies in species that may already have microsatellites, but are being conducted far from the region where individuals were collected for original development of species-specific loci.