The Barrens Darter, Etheostoma forbesi, is one of the most geographically restricted freshwater fish species in North America, with a distribution limited to headwater portions of nine streams in the western part of the upper Caney Fork, a tributary of the Cumberland River in Tennessee. This limited geographic distribution makes Etheostoma forbesi especially vulnerable to potential threats posed by human alterations to rivers and streams, and the risk of ecological competition and introgressive hybridization with the closely related Fringed Darter, Etheostoma crossopterum. Museum collection records and targeted surveys conducted since its description suggest that present-day range of Etheostoma forbesi does not include several streams it previously inhabited—some as recently as 15 years ago. We investigate the geographic distribution and variation in meristic traits of both Etheostoma forbesi and Etheostoma crossopterum in the upper Caney Fork system through the examination of all available museum vouchers, and assess phylogeographic patterns among populations using mitochondrial DNA sequence data. We report a newly discovered population of Etheostoma forbesi from the upper Collins River, and present evidence that Etheostoma crossopterum has displaced Etheostoma forbesi in the Hickory Creek system and Mud Creek in the upper Barren Fork River system. There are no differences in scale counts between the two species, but the sum of the number of rays in the anal, pectoral, and second dorsal fins is diagnostic. Analysis of mtDNA variation indicates gene flow between Etheostoma forbesi and Etheostoma crossopterum. Our results suggest that sympatry of the two species in the western upper Caney Fork system is a potential threat to the persistence of Etheostoma forbesi.

Pencil-tailed Tree Mice (Muridae: Chiropodomys) are small arboreal mammals endemic to the rainforests of Southeast Asia. They are capable of manual and pedal grasping and have nails rather than claws on their pollex and hallux, but their limb morphology has never been analyzed from functional, ecogeographic, or taxonomic perspectives. We compared two species of Chiropodomys to the similarly sized but terrestrial Mus musculus using quantitative morphometric osteological data recorded from six limb bones. Principal components analysis (PCA) clearly separated Chiropodomys from Mus. Multivariate and univariate analyses revealed several features linked to arboreality in Chiropodomys and characteristics associated with terrestriality in Mus. These include a wide medial epicondyle and shallow knee in Chiropodomys and a long olecranon process, long greater trochanter, and deep knee in Mus. PCA also distinguished mainland C. gliroides from island C. calamianensis of the Palawan Faunal Region, with the latter exhibiting larger body size, as predicted by the island rule. Finally, PCA clearly separated northeastern C. gliroides specimens collected north of the Isthmus of Kra from southwestern specimens collected on the Malay Peninsula south of the Isthmus of Kra; these preliminary results may indicate that there are two distinct taxa in this sample, but this must be tested with more specimens and data. Overall, our study revealed functional differences related to substrate preference, larger body size in an island endemic species, and postcranial evidence for an additional mainland taxon.

A review is given of the zoological names and current taxonomic status of two genera and 21 species-group taxa of hydroids attributed in this work to Addison Emery Verrill of the United States. Information is provided on type localities of his new species, and on locations and kinds of type material known to exist. The genus BlastothelaVerrill, 1878 is held to be congeneric with Candelabrumde Blainville, 1830, and its type species, B. roseaVerrill, 1878, is provisionally assigned to the synonymy of C. phrygium (Fabricius, 1780). Syntypes of Halecium robustumVerrill, 1873a, once thought lost, have been rediscovered at the Peabody Museum of Natural History at Yale University and the Smithsonian National Museum of Natural History, and an earlier neotype designation of the species is set aside. Sertularia achilleae Verrill, in Coues and Yarrow, 1878, a widely overlooked nominal species, is taken to be conspecific with Tridentata marginata (Kirchenpauer, 1864). Sertularia carolinensisVerrill, 1872b, another poorly known species, is recognized as valid and a senior synonym of Thuiaria plumuliferaAllman, 1877. A review is given of the taxonomic and nomenclatural status of the polyseriate sertulariid genera PericladiumAllman, 1876 and PolyseriasMereschkowsky, 1877. Authorship and date of the binomen Laomedea angulata, usually attributed to Thomas Hincks with a date of 1861, is shown to have been made available earlier by Hincks in an 1859 article. Plumularia gracillimaG.O. Sars, 1873, assigned at present to the halopteridid genus PolyplumariaG.O. Sars, 1874, is taken to be a plumulariid. It is provisionally returned to PlumulariaLamarck, 1816, although that genus is considered polyphyletic and in need of revision. Bibliographic work was undertaken to determine, as accurately as possible, dates of publication of the 47 papers authored by Verrill containing information on hydroids and hydromedusae. An annotated checklist of 138 species of hydrozoans reported in those works, including 47 anthoathecates, 90 leptothecates, and 1 trachymedusa, is included as an appendix.