Bufo cavifrons

Number of Pages: 3Integrative BiologyGeological Science

Geographic Variation in Bufo valliceps (Anura: Bufonidae), a Widespread Toad in the United States and Middle America

The common lowland toad Bufo valliceps has a large distribution in the southern United States, Mexico, and most of Central America; this ample distribution across diverse temperate and tropical habitats is unusual among frogs. Geographic variation in size, shape, skin texture, and color pattern among populations of this species was reviewed. Although there are great differences between extreme northern and southern populations, I did not find smooth clinal variation for any character examined. Nor is there a discrete break among these continuous morphological variables that separate the the northern and southern morphs. Variation in Biifo valliceps is characterized by a high degree of inter- and intrapopulational variation that cannot be attributed to simple trends associated with latitude, elevation, or climate. An analysis the relationship between body size and aridity, along a precipiation gradient on the Yucatan Peninsula, found no consistent covariation. Previous claims for a positive relationship between elevation and degree of development of the cranial crests were found not to be accurate. Although the several relatively distinct populations are referable to the taxa Bufo nebulifer and Bnfo valliceps wilsoni, 1 do not propose recognition of these taxa, pending further research

Systematics of the Bufo Valliceps Group (Anura: Bufonidae) of Middle America

The University of Kansas has long historical connections with Central America and the many Central Americans who have earned graduate degrees at KU. This work is part of the Central American Theses and Dissertations collection in KU ScholarWorks and is being made freely available with permission of the author through the efforts of Professor Emeritus Charles Stansifer of the History department and the staff of the Scholarly Communications program at the University of Kansas Libraries’ Center for Digital Scholarship.A phylogenetic analysis of morphological characters revealed that the species content of the Bufo valliceps group is limited to eight species (two of them new) occurring between the southern United States and Costa Rica. Several Middle American species usually associated with this group are shown to be closely related, but outside of the Bufo valliceps group. The monotypic genus Crepidophryne is placed in the synonymy of Bufo. The taxon Bufo valliceps macrocristatus is recognized as a species distinct from Bufo valliceps. Seven species in the Bufo valliceps group appear to be allopatric with respect to one another and are restricted to humid primary forest habitat on the lower slopes of the major mountain ranges of southern Mexico, Guatemala, Honduras, and Costa Rica. The species Bufo valliceps is widespread in humid lowland habitats from the southern United States to Costa Rica that are either naturally more open (e.g., savanna) or disturbed secondary growth. There are great differences in size, shape, skin texture, and color pattern between northern and southern populations of this species; however, these differences do not vary along a smooth cline among populations from intermediate areas. Nor is there a discrete break among these continuous variables that separate the northern and southern morphs. Variation in Bufo valliceps is characterized by a high degree of. inter- and intrapopulational variation that cannot be attributed to simple trends associated with latitude, altitude, or climate. Bufo ibarrai, long assumed to be in the Bufo valliceps group but here shown to lie outside of the group, is reviewed and rediagnosed with respect to other similar Central American toads. The taxon Bufo valliceps microtis is placed in the synonymy of Bufo coccifer. Diagnostic accounts for all species in the Bufo valliceps group and a key to the species are provided

Daphnia predation on the amphibian chytrid fungus and its impacts on disease risk in tadpoles

Direct predation upon parasites has the potential to reduce infection in host populations. For example, the fungal parasite of amphibians, B atrachochytrium dendrobatidis ( B d), is commonly transmitted through a free‐swimming zoospore stage that may be vulnerable to predation. Potential predators of B d include freshwater zooplankton that graze on organisms in the water column. We tested the ability of two species of freshwater crustacean ( D aphnia magna and D . dentifera ) to consume B d and to reduce B d density in water and infection in tadpoles. In a series of laboratory experiments, we allowed D aphnia to graze in water containing B d while manipulating D aphnia densities, D aphnia species identity, grazing periods and concentrations of suspended algae ( A nkistrodesmus falcatus ). We then exposed tadpoles to the grazed water. We found that high densities of D . magna reduced the amount of Bd detected in water, leading to a reduction in the proportion of tadpoles that became infected. Daphnia dentifera , a smaller species of D aphnia , also reduced B d in water samples, but did not have an effect on tadpole infection. We also found that algae affected B d in complex ways. When D aphnia were absent, less B d was detected in water and tadpole samples when concentrations of algae were higher, indicating a direct negative effect of algae on B d. When D aphnia were present, however, the amount of B d detected in water samples showed the opposite trend, with less B d when densities of algae were lower. Our results indicate that D aphnia can reduce B d levels in water and infection in tadpoles, but these effects vary with species, algal concentration, and D aphnia density. Therefore, the ability of predators to consume parasites and reduce infection is likely to vary depending on ecological context. We tested the ability of two species of freshwater crustacean ( Daphnia magna and D. dentifera ) to consume zoospores of the amphibian parasite, Batrachochytrium dendrobatidis (Bd), and to reduce parasite density in water and infection in tadpoles. In a series of laboratory experiments, we allowed Daphnia to graze in water containing Bd, then exposed tadpoles to the grazed water. Our results show that Daphnia can reduce Bd levels in water and infection in tadpoles, but these effects vary with species, algal concentration and Daphnia density.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/100311/1/ece3777.pd

The Oral and Skin Microbiomes of Captive Komodo Dragons Are Significantly Shared with Their Habitat.

Examining the way in which animals, including those in captivity, interact with their environment is extremely important for studying ecological processes and developing sophisticated animal husbandry. Here we use the Komodo dragon (Varanus komodoensis) to quantify the degree of sharing of salivary, skin, and fecal microbiota with their environment in captivity. Both species richness and microbial community composition of most surfaces in the Komodo dragon's environment are similar to the Komodo dragon's salivary and skin microbiota but less similar to the stool-associated microbiota. We additionally compared host-environment microbiome sharing between captive Komodo dragons and their enclosures, humans and pets and their homes, and wild amphibians and their environments. We observed similar host-environment microbiome sharing patterns among humans and their pets and Komodo dragons, with high levels of human/pet- and Komodo dragon-associated microbes on home and enclosure surfaces. In contrast, only small amounts of amphibian-associated microbes were detected in the animals' environments. We suggest that the degree of sharing between the Komodo dragon microbiota and its enclosure surfaces has important implications for animal health. These animals evolved in the context of constant exposure to a complex environmental microbiota, which likely shaped their physiological development; in captivity, these animals will not receive significant exposure to microbes not already in their enclosure, with unknown consequences for their health. IMPORTANCE Animals, including humans, have evolved in the context of exposure to a variety of microbial organisms present in the environment. Only recently have humans, and some animals, begun to spend a significant amount of time in enclosed artificial environments, rather than in the more natural spaces in which most of evolution took place. The consequences of this radical change in lifestyle likely extend to the microbes residing in and on our bodies and may have important implications for health and disease. A full characterization of host-microbe sharing in both closed and open environments will provide crucial information that may enable the improvement of health in humans and in captive animals, both of which experience a greater incidence of disease (including chronic illness) than counterparts living under more ecologically natural conditions