Occurrence of the Sinus Nematode Skrjabingylus sp. (Nematoda: Metastrongyloidea) Inferred from Sinus Lesions in Arkansas Mustelidae and Mephitidae, with review of relevant literature

Nasal nematodes of the genus Skrjabingylus occur in the mammalian families Mustelidae and Mephitidae, and have been found from Canada to Costa Rica. Ingestion of infected snails, frogs, snakes, or mice can lead to infection of these mammalian hosts. Infection often causes pathology to bones in the sinus region, which may lead to discoloration, enlargement, and fenestrations of the bone. Examination of museum specimens for bone lesions or other evidence of infection has been used to evidence prior infection, but prevalence and intensity cannot be interpreted without actually recovering the parasite. We examined Mustelids and Mephitids in collections of mammals housed at Arkansas State University (ASU), Henderson State University (HSU), and the University of Arkansas at Little Rock (UALR) to evaluate the possible occurrence of nasal nematodes in Arkansas mammals. Evidence of infection was found in skulls of the Striped Skunk (Mephitis mephitis), Spotted Skunk (Spilogale putorius), Mink (Neovison vison), Long-tailed Weasel (Mustela frenata), and North American River Otter (Lontra canadensis) from Arkansas. We report for the first time evidence of the presence and distribution of Skrjabingylus sp. infecting mammals in Arkansas

Mensural Discrimination of the Skulls of Arkansas Peromyscus

Twelve parameters were measured on skulls of four species of Peromyscus from Arkansas. Univariate statistical tests, multivariate analyses of variance, and principal axis factor analyses were performed on the data set and/or subsets in a search for species-level discriminating characters. Total length of skull was found to discriminate between skulls of P. maniculatis, P. leucopus, and a combined group of P. attwateri and P. gossypinus. Furthermore, the ratio of interorbital width and length of nasal bone was found to adequately discriminate between skulls of P. attwateri and P. gossypinus

Investigation of Fluorescence in Selected Mammals of Arkansas

The adaptive value of fluorescence among the vertebrates has been studied most in fishes and birds, and only a few observations have been published regarding fluorescence in the pelage of mammals. Recently, reports of fluorescence in some marsupials, the platypus, and in flying squirrels have become available. We report the occurrence of fluorescent properties in some mammals from Arkansas. Most carnivores, bats, and rodents did not exhibit the property when viewed under UV light. However, opossums, rabbits, a weasel, muskrats, and moles showed substantial UV response, and a few other mammals showed minor fluorescence. Colors fluoresced included pink, green, and light cyan. Most species exhibited only one color, but the opossum responded with 2 colors. Potential explanations for positive responses to UV light include species signaling, mate assessment, predator avoidance, or prey location. Alternatively, the response may be an artifact without adaptive significance

Sex-ratio of Miridae (Hemiptera) taken via UV light-traps in Arkansas, USA.

We determined the sex-ratio of 1,095 plant bugs (Hemiptera: Miridae) taken from 60 individual UV light-trap samples in Clark County, Arkansas over a two year period. We found that of the 21 taxa in which a sex-ratio determination could be made, 61.9% of them (13 of 21) contained a majority (over 50%) of males. Three taxa were exclusively represented by males, while two taxa were exclusively represented by females. Although taxa dependent, our data indicate that male mirids are, in general, more frequently encountered in UV light-traps. However, contrary to the notion that sparked this study (see herein) light-trap content was not represented vastly to exclusively by male individuals as the sex-ratio of the cumulative data was 62.47% males (684) and 37.53% females (411)

The Reproductive Season of the Highland Stoneroller, Campostoma spadiceum, Evidenced by Museum Specimens

The Highland Stoneroller (Campostoma spadiceum) was described as a distinct species in 2010. Since then, the only study specific to this species is a survey of distribution, and nothing is known about reproduction. We examined 134 lots including 315 specimens of C. spadiceum housed in the Henderson State University collection of fishes to evaluate the timing of reproductive events. We dissected individuals to reveal sex and reproductive status. Females as small as 49 mm total length were able to yolk eggs, and follicles were in development by October. Ripe eggs were present in specimens collected from January through May, but were most common in March through May. Several females had oviposited in early March, but most specimens that appeared to have spawned had done so likely in April. Nuptial tubercles appeared on males as early as January and February, but most adult males were fully tubercled from March through May

Comments on Estimating Population Rate of Increase from Age Frequency Data

Although many papers have described assumptions and calculations of r from different kinds of data, none has compared estimates of r for the same real data set under different assumptions. We used the age distributions of gray foxes collected during six trapping seasons to estimate and compare r and lₓ series derived under different assumptions. Because trapped foxes are killed, they are believed by some to represent death history data. We found this treatment underestimates mortality so overestimates survivorship and leads to erroneous conclusions about the population. Use of a projection matrix allowed prediction of population size and thus allowed us to predict observed rate of increase. Use of projection matrices also resulted in the most conservative estimated of r