Fundulus Catenatus Research Articles

Draft genome assemblies using sequencing reads from Oxford Nanopore Technology and Illumina platforms for four species of North American Fundulus killifish

BackgroundWhole-genome sequencing data from wild-caught individuals of closely related North American killifish species (Fundulus xenicus, Fundulus catenatus, Fundulus nottii, and Fundulus olivaceus) were obtained using long-read Oxford Nanopore Technology (ONT) PromethION and short-read Illumina platforms.FindingsDraft de novo reference genome assemblies were generated using a combination of long and short sequencing reads. For each species, the PromethION platform was used to generate 30–45× sequence coverage, and the Illumina platform was used to generate 50–160× sequence coverage. Illumina-only assemblies were fragmented with high numbers of contigs, while ONT-only assemblies were error prone with low BUSCO scores. The highest N50 values, ranging from 0.4 to 2.7 Mb, were from assemblies generated using a combination of short- and long-read data. BUSCO scores were consistently >90% complete using the Eukaryota database.ConclusionsHigh-quality genomes can be obtained from a combination of using short-read Illumina data to polish assemblies generated with long-read ONT data. Draft assemblies and raw sequencing data are available for public use. We encourage use and reuse of these data for assembly benchmarking and other analyses.

Field verification of chondroitin sulfate as a putative component of chemical alarm cue in wild populations of fathead minnows (Pimephales promelas)

Chemical characterization of damage-released alarm cues in ostariophysan fishes has lagged far behind the study of the ecological role that these cues play in behavioral decision-making of prey fishes. Chondroitin sulfate has been identified as a putative component of alarm cue based on two laboratory studies of zebrafish, Danio rerio, and the northern studfish, Fundulus catenatus. The fathead minnow, Pimephales promelas, is a model organism in the study of chemically mediated predator–prey interactions, in part because they can be studied in the laboratory and under field conditions. Here, we conducted a field experiment on wild populations of fathead minnows, to test for area avoidance of chondroitin sulfate relative to conspecific skin extract (containing alarm cues = positive control) or water (negative control). We repeated the experiment in two small lakes in central Minnesota using minnow traps containing blocks of sponge with one of the three test cues. We found that fathead minnows avoided traps chemically labeled with conspecific alarm cue more than control traps labeled with water, and that the number of minnows caught in traps labeled with chondroitin sulfate was intermediate between alarm cue traps and water traps. These data are consistent with laboratory findings that chondroitin sulfate is a component of alarm cue, but that other species-specific compounds are needed for a full behavioral response.

Fundulus catenatus(Northern Studfish) Response to the Potential Alarm Cue Chondroitin Sulfate

Abstract The evolution of organismal cue-response systems can allow for an effective behavioral reaction to various environmental signals. In aquatic habitats, the reception of certain chemical cues can increase individual fitness of organisms by serving as an indicator of predation threat. In some fish species, damage to an individual's epidermal cells causes release of a substance that functions as an alarm cue and consequently initiates defense responses in neighboring prey. Recent research on the chemical makeup of the substance that elicits an anti-predator response in Danio rerio (Hamilton) (Zebrafish) revealed that chondroitin fragments were a key component in this substance. The goal of our study was to investigate the ability of chondroitin to elicit an alarm response in Fundulus catenatus (Storer) (Northern Studfish). This species is a small-bodied killifish native to southeastern to south-central USA and is associated with topwater habitats near aquatic and/or overhanging vegetation. We hypothe...

Species delimitation and phylogeography of the studfishFundulus catenatusspecies group (Ovalentaria: Cyprinodontiformes)

The Central Highlands of North America have an old and complex geological and biological history, with extensive unexplored cryptic diversity. We examined the species limits of the Fundulus catenatus species group (F. catenatus, Fundulus bifax, and Fundulus stellifer) using two phylogenetic approaches. Fundulus catenatus was densely sampled from five geographically disjunct regions across the eastern USA. We sequenced four nuclear introns and used species tree analyses and two species delimitation methods to determine historical relationships and investigate species diversity within the group. Both methods strongly supported the presence of two reciprocally monophyletic species within F. catenatus. Species tree analysis of four nuclear introns (stx5a, ncl1, rpsa, and rps3) from the F. catenatus species group (including a tip for F. sp. cf. catenatus) recovered the two Mobile Basin species as sister to a strongly supported clade of F. catenatus and F. sp. cf. catenatus. Cytochrome b sequences were used in phylogeographical analyses of the two putative species. In one species we identified signatures of population expansion whereas the other exhibited genetic structure consistent with isolation of populations.

Helminth Parasites of the Northern Studfish, Fundulus catenatus (Cypriniformes: Fundulidae) from the Ouachita and Ozark Mountains of Arkansas, U.S.A.

ABSTRACT: Between May 2014 and September 2014, 50 Northern Studfish, Fundulus catenatus, were collected from sites in the interior highlands of the Ouachita Mountains (n = 25) and Ozark Mountains (n = 25) of Arkansas and examined for helminths. Twenty-three (46%) of the northern studfish, including 7 (28%) from the Ouachitas and 23 (92%) from the Ozarks were infected with helminths. These included 8 (16%) with Neascus-type metacercariae (black grub), 4 (8%) with metacercaria of Clinostomum marginatum, 8 (16%) with Creptotrema sp., 1 (2%) with Posthodiplostomum minimum, 3 (6%) with immature Proteocephalus sp., 9 (18%) with larval Eustrongylides sp., 1 (2%) with Rhabdochona cascadilla, 2 (4%) with larval Spinitectus sp., and 17 (34%) with acanthocephalan cystacanths. In addition, 6 of 8 individuals (75%) from one site in the Ouachitas harbored the monogenean, Salsuginus fundulus. We document new host records for most of these helminths and new distributional records for Creptotrema sp., Eustrongylides ...

Agonistic behavioral interactions between introduced western mosquitofish and native topminnows

The stocking of western mosquitofish Gambusia affinis for mosquito control negatively impacts native fishes with similar ecological requirements. In this study, a series of laboratory microcosm experiments was used to examine intra and interspecific agonistic behavioral interactions (e.g., chases and nips) between western mosquitofish and northern starhead topminnow Fundulus dispar, northern studfish F. catenatus, blackstripe topminnow F. notatus, and banded killifish F. diaphanous at three fish densities and in the presence/absence of vegetation. Western mosquitofish exhibited more agonistic behaviors than the four topminnow species and caused a change in topminnow behavior in mixed-species microcosms. Mosquitofish were aggressive toward conspecifics, with most of the chases and nips occurring at the highest densities and when vegetation was absent. Topminnows exhibited few agonistic behaviors toward conspecifics, but intraspecific chasing and nipping did occur when exposed to mosquitofish. Agonistic behaviors by topminnows toward mosquitofish occurred infrequently, and mosquitofish initiated almost all of the chases and nips. While all four topminnow species were attacked by mosquitofish, northern starhead topminnow and banded killifish were chased and nipped more frequently than the other topminnow species. These two topminnows exhibited the most behavioral changes and fin damage and one northern starhead topminnow died following mosquitofish attacks. Based on these results, it appears that the stocking of western mosquitofish into primary and connecting waterways could have negative impacts on native topminnow species that occur in these systems.

Morphology and Phylogeny of the Studfish Clade, Subgenus Xenisma (Teleostei: Cyprinodontiformes)

Abstract Phylogenetic relationships within the studfish clade, subgenus Xenisma, were elucidated using parsimony analysis of 21 morphological transformation series, primarily osteology and external morphology. The analysis supports monophyly of subgenus Xenisma and the studfishes sensu strictu (Fundulus bifax, Fundulus catenatus, and Fundulus stellifer). Fundulus julisia and Fundulus albolineatus are recognized as sister taxa and together are recognized as sister to the F. bifax, F. catenatus, and F. stellifer clade. Contrary to a previous allozyme study of the subgenus, Fundulus rathbuni is recognized as sister to a monophyletic group composed of all other Xenisma species. This relationship is biogeographically consistent with the vicariant pattern previously demonstrated within darters of the subgenus Percina and suckers of the genus Hypentelium. The biogeography of the rest of subgenus Xenisma is complex and the sister-group relationship between F. catenatus and F. bifax is recognized as anomalous when...

INTRASPECIFIC PHYLOGEOGRAPHY OF NORTH AMERICAN HIGHLAND FISHES: A TEST OF THE PLEISTOCENE VICARIANCE HYPOTHESIS.

The highland fish fauna of eastern North America consists of Appalachian and Ozark centers of endemism separated by the intervening Glacial Till Plains. Clades within these areas are more closely related phylogenetically to each other than to clades occurring in the intervening formerly glaciated region, suggesting that the Pleistocene glaciations fragmented a widespread highland region and its associated fauna. Alternatively, it is possible that these faunal assemblages predate the glaciations or that recent dispersals may have been more important than vicariance in determining faunal compositions. We examined the relationships among mitochondrial DNA (mtDNA) haplotypes within five clades of highland fishes, each with a distribution suggestive of a Pleistocene vicariance event. Darters of the subgenera Litocara and Odontopholis have distributions and mtDNA relationships that are consistent with the Pleistocene integration and burial of the Teays-Mahomet valley, a major drainage of the early Pleistocene. The distribution and mtDNA relationships among subspecies of Erimystax dissimilis are not consistent with Pleistocene vicariance, but relationships among Appalachian haplotypes are consistent with the late Pleistocene integration of the modern Ohio River system. Both Cottus carolinae and the Fundulus catenatus species group have representatives in the Mobile basin consistent with pre-Pleistocene divergences. Three haplotype clusters were found in C. carolinae, corresponding to the Appalachian, Ozark, and upper Kanawha River populations. However, Appalachian and Ozark F. catenatus populations are paraphyletic with respect to each other. This, coupled with a relatively low degree of sequence divergence, suggests that no long-term barriers to gene flow exist for C. carolinae and F. catenatus. These three distinct phylogeographic patterns indicate that Pleistocene vicariance is not the only explanation for the Appalachian-Ozark distribution of highland fish communities.

Influence of salinity on the rates of oxygen consumption in two species of freshwater fishes, Phoxinus erythrogaster (family Cyprinidae), and Fundulus catenatus (family Fundulidae)

A dye process in a textile plant in southern Kentucky (USA) produces large quantities of saline waste-water which eventually enter Lake Cumberland via a municipal sewage treatment plant on Lily Creek. The impact of hypersaline conditions on two fish species native to the Cumberland River drainage system, redbelly dace (Phoxinus erythrogaster) and northern studfish (Fundulus catenatus), was assessed. These species were subjected to salinities of 0, 4, and 10‰ after which routine oxygen consumtpion values were determined. Significant correlations of salinity with oxygen consumption were demonstrated for both species with P. erythrogaster showing greater overall impact of salinity on metabolic rate.

Evolutionary and Biogeographic Relationships of Fundulus catenatus (Fundulidae)

Evolutionary relationships among 21 geographic samples of the northern studfish, Fundulus catenatus, were inferred from genotype distributions at 24 presumptive gene loci. Phylogenetic treatment of allozymic data support a widespread ancestral distribution for the species in the region of the Central Highlands. Allozymic data further support a primary divergence between a Cumberland, Green, and Tennessee River segment of this ancestral distribution and an Indiana, lower Mississippi River, Ouachita, and Ozark population. Disjunct populations extant in the Ouachita Uplands represent an early divergence from an Indiana-Ozark-lower Mississippi River lineage. The White River, Indiana, and Ozark populations remain close relatives, with the lower Mississippi River populations diverging from this lineage. The inferred pattern of relationships is generally consistent with predictions based on recent hypotheses concerning the historical biogeography of the Central Highlands. One noteworthy point of divergence concerns the apparent close relationship between Ozark and Indiana populations. Such a pattern of relationship supports the persistence of gene flow across the region that is now the Central Lowlands after isolation of the Ouachita Highlands.

The effect of hypophysectomy, prolactin and ACTH on survival and electrolyte levels of the freshwater cyprinodont, Fundulus catenatus

1. 1. The freshwater cyprinodonts Fundulus catenatus were tested for their ability to survive in fresh water, post hypophysectomy. 2. 2. Hypophysectomized animals lived well in 17% sea-water, but were unable to survive in fresh water. 3. 3. Hypophysectomy resulted in a steady loss of electrolytes due to a marked reduction in the animal's ability to balance salt uptake with salt loss. 4. 4. Replacement therapy with prolactin, ACTH and prolactin and ACTH, had no significant effect on survival. 5. 5. F. catenatus appear very susceptible to laboratory stress and any positive response to hormone therapy may have been overwhelmed by stress effects.

Ecology of Fundulus catenatus in Three Interconnected Stream Orders

Fundulus catenatus, the northern studfish, was studied in tributaries of the Green River, Casey Co., Kentucky. Spawning occurred from April through July and males are in breeding color. Many studfish live to age 3 + years and attain lengths of 85-115 mm. Peak feeding occurred in the morning and late afternoon. Most food items were taken from the substrate and water column of the stream. Immature and adult diptera were the most important foods eaten by all age groups during autumn, spring and summer months. Important food items consumed by age 0 fish included crustaceans, Hydrocaria, rotifers, gastropods, nematodes and Hymenoptera. Major food items eaten by older fish are Ephemeroptera nymphs, Trichoptera, Coleoptera adults, nematodes and Hymenoptera. Studfish disappeared from the collection sites in the late autumn and returned in April. INTRODUCTION Fundulus catenatus (Storer) (Teleostei, Cyprinodontidae), the northern studfish, lives in clear sand and gravel-bottomed streams of central and southern United States (Pflieger, 1971). Thomerson (1969) compared morphological variation and systematic relationships of F. catenatus and F. stellifer. McCaskill et al. (1972) examined gut contents of 200 + specimens and observed feeding behavior in the field. Duff and Fleming (1972) have examined sodium metabolism and osmoregulation in the northern studfish. This study describes aspects of the life history of Fundulus catenatus from three interconnected streams of different orders on the South Fork of the Green River, Casey Co., Ky. Stream ordering is a method of grouping streams with similar physical and biological conditions (Horton, 1945). Unbranched tributaries are called first order. The union of equal-order streams form the next higher order; that is, the union of two first-order streams forms a second-order stream. STUDY AREA The Green River drainage system contains relatively undisturbed and abundant populations of Fundulus catenatus on its South Fork. Station I, 8.7 miles S of Liberty at Highway 127 crossing, is on a 2-mile-long fifth-order stream that has average gradient drop of 12.5 ft per mile. At Station I, the stream is from 30-70 feet wide and from a few inches to 4 ft deep. Station II is upstream ca. 2 miles on the fourth-order portion of the Trace Fork tributary, 0.8 miles E of Phil, next to Highway 501. This fourth-order stream, 3 miles long with average gradient drop of 17 ft per mile, varies from 20-30 ft wide and from a few inches to 3 feet in depth. Station III, 4 miles upstream from Station II, is located on Rowe Branch, a second-order stream, 0.9 miles NE of Gilpen. This second-order stream segment, 3.5 miles long with average gradient drop of 34 ft per mile, is 5-15 feet wide and from a few inches to 2 feet deep. Most studfish from these stations were collected near the shore in gravel-bottomed pools less than 1 ft deep. A 24-hr collection to determine circadian feeding intensity was made from the thirdorder segment of the Trace Fork tributary, ca. 1.5 miles downstream from Station III. METHODS Between August 1977 and September 1978, 13 monthly collections of northern studfish were obtained using a 3.6 m, 4.8 mm mesh nylon seine. All collections were taken between 1600 and 1830 hr. During the warmer months, 20-30 specimens were

The Fishery of a Missouri Ozark Stream, Big Piney River, and the Effects of Stocking Fingerling Smallmouth Bass

Abstract Over 92,000 marked fingerling smallmouth bass were stocked in Big Piney River, 1952-1955. An estimated 63,600 smallmouth bass were caught between 1953, when the first stocked fish entered the creel, and 1958 when no more marked fish were caught. Of that number, not more than 2,100 were stocked fish. This is a little more than 3% of all the bass caught and a little more than 2% return of stocked fish. Seventy species of fish were collected between 1951 and 1958 with electric shockers, hoopnets, and seines. Golden redhorse, rock bass, black redhorse, northern hog sucker, smallmouth bass and longear sunfish made up 80% of the total weight. The Ozark minnow, bleeding shiner, northern studfish, stoneroller, and bluntnose minnow were the most important forage species. This species composition is representative of Ozark headwater streams. Mean annual catch rates ranged from 35.2 to 134.9 kg/10 shocker hr of which 2.3 to 13.6 kg/10 shocker hr was bass. Big Piney River is subject to flash floods with cres...

Food of the Northern Studfish, Fundulus catenatus, in the Missouri Ozarks

Food of the Northern Studfish, Fundulus catenatus, in the Missouri Ozarks

Sodium metabolism of the freshwater cyprinodont,Fundulus catenatus

1. Transfer of the freshwater cyprinodont,Fundulus catenatus, into 40% sea water caused a slow rise in serum sodium levels, total body sodium, and the rate of sodium efflux. 2. Serum sodium levels were first reduced by expanding sodium space. In some cases the animals eventually brought sodium parameters (except efflux) back to fresh water levels; in other cases the sodium space remained expanded. 3. Transfer of animals adapted to 40% sea water on to 52% or 65% sea water caused a second rise in the sodium load and expansion of the sodium space. The animals could not survive indefinitely in 65% sea water. 4. Water permeability first decreased, and then increased after transfer into saline. The chenges in water permeability correlated roughly with changes in serum cortisol levels. 5. The animals remained hyposmotic to the environment in both 40% and 65% sea water and drank sufficient sea water to stay in positive water balance. They were not able carry out a net excretion of sodium in salinities above 40% sea water.

Stream Capture in Kentucky Indicated by Distributional Records of Fundulus catenatus and Etheostoma spectabile

Stream Capture in Kentucky Indicated by Distributional Records of Fundulus catenatus and Etheostoma spectabile

Further studies on the effect of mammalian parathyroid extract on the serum calcium levels of two closely related teleosts

1. 1. The effect of mammalian PTH on the turnover of serum calcium, as judged by Ca 45 assay, on Fundulus catenatus during the breeding season, and on Fundulus kansae during the post-breeding season has been studied. 2. 2. F. catenatus and the male F. kansae did not respond to PTH; female F. kansae which had been exposed to estradiol benzoate showed decreased serum Ca following PTH injections. 3. 3. It is concluded that F. catenatus does not respond to PTH at any time, and that the response found in the female F. kansae is probably dependent upon estrogen conditioning.

Additions to the Fish Fauna of Oklahoma with a Summary of Introduced Species

Report of the collection and distribution in Oklahoma of six fishes not previously recorded from the state (Salmo trutta, Hiodon tergisus, Ictalurus nebulosus, Typhlichthys subterraneus, Fundulus catenatus, Roccus saxatilis) brings the total number of species known from Oklahoma to 167. Three of the six represent introduced forms. A list of all exotic fishes known to be introduced into Oklahoma waters, with the available history of introduc- tion, is included. Of the 14 known or postulated to be introduced, 5 are utilized as bait species and 9 were introduced as additional food for game fishes. Eight have had varying degrees of reproductive success; 5 of the game fishes were not expected to provide reproducing populations, and their success is depen- dent on continual restocking. Only the introduction of the tench, Tinca tinca, can be considered unsuccessful.