We report updated ranges for four sympatric species of Pirate Perches following a recent taxonomic revision of Aphredoderus. Using observations from recent sampling by the North Carolina State Museum of Natural Sciences and reidentifying cataloged specimens from the Georgia Museum of Natural History and Auburn University Museum collections, we were able to refine the distributions of four species throughout a complicated sympatric zone spanning coastal plain drainages in Alabama, Florida, and Georgia. We find that A. gibbosus is present in low numbers in the Flint, Escambia, Choctawhatchee, and Chattahoochee basins. These additional records nearly link the previously reported disjunct distribution of A. gibbosus into a more continuous distribution, though it still appears to be rare in this part of its range. We identified A. ornatus in Patsiliga Creek (Flint basin), and A. mesotrema in basins between the Mobile River and the Escambia River, and in the Alabama River. Following field observations that A. retrodorsalis is only present at low elevations, we narrow the range this species to being generally below 65 meters elevation in basins from the Blackwater River in Florida to the Ogeechee River in Georgia. This pattern contrasts with the sympatric species A. ornatus, which extends to (and at times past) the Atlantic Coastal Plain fall line in Georgia.
The Bridle Shiner, Notropis bifrenatus (Cope, 1867), Family Leuciscidae, is a small minnow species that ranges in Atlantic coastal river drainages of eastern North America from the St. Lawrence in Canada southward to the Santee River basin of South Carolina. Over several decades notable declines throughout its range have been observed and multiple natural resource agencies note it to be jeopardized with probable extirpations evident in a number of drainages. The Virginia Department of Game and Inland Fisheries recognized the need to assess the status of the Bridle Shiner within its historical range in Virginia. Here we report the results of field surveys and preliminary molecular investigations undertaken to evaluate the species' current distribution and status. Currently, in Virginia, all remaining documented populations are confined to the greater James River basin in the Coastal Plain and lower Piedmont. Based on our findings, recommendations are made for targeted future sampling efforts to enhance detection of small, isolated populations of Bridle Shiner.
Cyprinella leptocheilus sp. nov., Siouan Thinlip Chub, is described as a new species that is endemic to Sand Hills and upper Coastal Plain streams in North Carolina and South Carolina. Recognized as an undescribed species since the early 1970s, this fish was known in the literature and in museum electronic databases as Hybopsis n. sp., H. sp. cf. zanema, Cyprinella n. sp., and C. sp. cf. zanema. Unofficially, it had gone by the common name Thinlip Chub. It was thought to be closely related to the two other barbeled Cyprinella species: Thicklip Chub, C. labrosa, and Santee Chub, C. zanema. Cyprinella leptocheilus is geographically, phenotypically, and genetically distinguishable from these two species. Cyprinella leptocheilus is confined to the Sand Hills and Coastal Plain regions of the Carolinas, whereas C. labrosa and C. zanema are more widely distributed in the Piedmont and Eastern Blue Ridge Foothills regions of the Santee River and Yadkin-Pee Dee River basins in the Carolinas and Virginia. Morphological differences detected were associated with the position of the dorsal-fin origin relative to the pelvic-fin origin; male tuberculation patterns and number of tubercles; upper lip thickness; mouth gape width; and the length of the maxillary barbel. Phylogenetic analyses of mitochondrial and mitochondrial-nuclear concatenated sequences consistently resolve each species as reciprocally monophyletic. Cyprinella leptocheilus is an evolutionary distinct sister to C. zanema; both are sister to C. labrosa. Within the C. leptocheilus clade, sequences from the Yadkin-Pee Dee River basin form a clade distinct from that of the Cape Fear River basin. These two clades are geographically isolated from one another. Given the divergence between the Cape Fear and Yadkin-Pee Dee River basins clades, it is recommended that these two C. leptocheilus clades receive protection as two evolutionarily significant units.
What relationship exists between Aethycteron sp. gill parasite infection and the reproductive characteristics of stripetail darters, Etheostoma kennicotti? 450 E. kennicotti were collected over 11 months from Estill Fork in Jackson County, Alabama. Gonads were removed and photographed. All oocytes were counted and then classified into one of four developmental stages based on size and appearance. Gill parasites belonging to the monogenean genus Aethycteron were excised, photographed, and counted. Sexual dimorphism in length and mass was observed in E. kennicotti. The number of males found at the 25> mm SL range far outnumbered the females while almost all individuals 25< mm SL were females. A high gonadosomatic index (GSI) was found in the females, with large (2 mm) size clutch oocytes. Female E. kennicotti were observed to be reproductively mature starting at 19 mm SL. Prevalence and intensity of infection by Aethycteron sp. parasites were high in both males and females, with prevalence reaching 90% in breeding condition individuals. Two hypotheses were tested to explain these phenomena. The first is that the lack of females in the larger size categories may be the result of a high cost of reproduction resulting in near-term reproduction being paid for at the expense of long-term survival. The second hypothesis tested is that fecundity compensation in females potentially causes the early reproductive maturation. The gender imbalance is likely the result of the sheer costs involved with reproduction, indicating high investment in current reproductive success with limited longer-term survival consistent with the fecundity compensation hypothesis.
Co-nest building and spawning among individuals of the native population of River Chub (Nocomis micropogon) and among those of an introduced population of Bluehead Chub (N. leptocephalus) observed in the Swannanoa River (French Broad River basin) during Spring 2024 represents the first time such behaviors have been documented between two species of Nocomis. Observations of these behaviors are described and discussed in the context of potential hybridization and the impact of introduced Bluehead Chubs in the French Broad River basin.
