Richard Mayden

• Ph.D.
• Professor and Endowed Chair Emeritus at Saint Louis University

Jawless vertebrates once dominated Palaeozoic waters, but just two lineages have persisted to the present day: lampreys and hagfishes. Living lampreys are a relatively small clade, with just over 50 species described, but knowledge of their evolutionary relationships has always been based on either a few mitochondrial genes or a small number of tax...

Fishes in the cypriniform family Catostomidae (suckers) are evolutionary tetraploids. The use of nuclear markers in the phylogenetic study of this important group has been greatly hindered by the challenge of identifying paralogous copies of genes. In the present study, we used two different methods to separate the gene copies of five single-copy n...

North American minnows of the Shiner Clade, within the family Leuciscidae, represent one of the most taxonomically complex clades of the order Cypriniformes due to the large number of taxa coupled with conserved morphologies. Species within this clade were moved between genera and subgenera until the community decided to lump many of the unclassifi...

Five ecologically and phenotypically divergent ecomorphs of the genus Salmo are known from a landlocked alpine lake in the Caucasus, Lake Sevan. It is an example of sympatric diversification within a species-rich lineage with predominate mode of speciation being allopatric. The diversification of Sevan trouts was accompanied by spawning resource pa...

The following supplementary files are included: 1. Figure legends for supplementary figures 2. Fig. S1 Full timetree.pdf 3. Fig. S2. Relationships among five tribes.pdf 4. Table S1. Sample information of the three nuclear datasets 5. Table S2. Sample information of the mitochondrial dataset

Despite the rarity of polyploidy in animals, some groups with polyploid species exhibit complicated and interesting patterns of reticulate evolution. Here we focus on fishes in the subfamily Cyprininae, the largest polyploid group of vertebrates. The large number of polyploid taxa poses significant challenges for phylogenetic and evolutionary studi...

Puntius sensu lato (s.l.) was one of the most speciose genera in the family Cyprinidae. There are around 120 valid species widely distributed in South‐East and South Asia, and South China. Puntius has long been known as an artificial assemblage and ‘catch‐all’ genus in which a large number of small, unrelated cyprinids have been placed. With new sp...

In the remote high-elevation streams and rivers in the northwest of Mexico, there is an endemic and highly diverse group of native trout related to the rainbow trout lineage (Oncorhynchus mykiss). Currently, only two species have been formally described from this trout complex, the Mexican golden trout, O. chrysogaster, and the San Pedro Mártir rai...

The Cypriniformes comprise approximately 4,200 species accounting for 25% of the diversity of all freshwater fish, which is widely distributed across the world’s continents except Antarctica, South America, and Australia. The highest species diversity is found in Southeastern Asia. Despite its remarkable species diversity and broad-scale geographic...

Appendix: list of species and genes analyzed.

Schonhuth et al-2018. Phylogeography of the widespread creek chub Semotilus!atromaculatus (Cypriniformes: Leuciscidae). Journal of Fish Biology 93: 778-791. Table S1 (Appendix): List of specimens analyzed for this study, indicating the number of specimens examined per gene for each locality, sampling locality, Tissue#, and catalog number for vouche...

Sevan trout, Salmo ischchan, dwelling in the mountain Lake Sevan (Caucasus) is a unique species complex. Four sympatric forms of Sevan trout were divergent in both their phenotypes and ecologies. Three forms were lacustrine spawners but were unique in their spawning times and the type of substrate. The fish community of Lake Sevan was strongly impa...

The extent and nature of genetic differentiation in Semotilus atromaculatus, one of the most abundant and widespread leuciscids in North America, were evaluated based on mitochondrial (mt) and nuclear DNA sequence variation. Phylogenetic relationships were first inferred based on a fragment of the cytochrome b (cytb) region and the nuclear intron s...

Catostomidae (“suckers”) is a diverse (76 species) and broadly distributed family of Holarctic freshwater fishes with a rich fossil record and a considerable number (∼35%) of threatened and imperiled species. We integrate DNA sequences (three mitochondrial genes, three nuclear genes), morphological data, and fossil information to infer sucker phylo...

Appendix S1. Catostomidae fossils, fossil and external calibration age priors, and additional discussion of phylogenetic relationships within the Catostominae.

Fig. S9. Probabilities of different character sets inferring the correct topology, a polytomy, or the incorrect topology (‘phylogenetic noise’) over the period of sucker subfamily divergence. The period investigated is the ‘subfamily divergence epoch’ (SDE; ∼63.16–34.37 Ma) in our time tree. The SDE defines an internode distance, t0, used in the pr...

Fig. S3. MrBayes consensus tree derived from the morphology dataset.

Fig. S5. MrBayes consensus tree derived from the nuclear IRBP dataset.

Fig. S6. MrBayes consensus tree derived from the concatenated nDNA dataset.

Fig. S7. Posterior density plots of BEAST ‘ucldStdev’ and ‘coefficient of variation’ statistics demonstrating significant among-lineage rate heterogeneity in the total-evidence dataset. Problematic mtDNA 1st and 3rd codon sites were excluded from the analysis.

Table S1. Data subsets and corresponding DNA substitution models selected in PartitionFinder for the four-locus dataset. Model selection analyses using PartitionFinder v1.1.1 supported different best-fit models of DNA evolution for different data subsets (i.e. groups or ‘blocks’ of data, such as sites filtered by codon positions). When it was not p...

Fig. S1. MrBayes consensus tree derived from the concatenated mtDNA dataset.

Fig. S2. MrBayes consensus tree derived from the mtDNA + morphology dataset.

Fig. S4. MrBayes consensus tree derived from the four-locus dataset.

Fig. S8. Variation in substitution rates among sites. This figure plots variation in substitution rates among sites, based on posterior distributions of the gamma shape parameters (alpha estimates) assigned to different data subsets in BEAST (excluding problematic mtDNA 1stand 3rd codon position sites).

The phylogenetic relationships and classification of the freshwater fish order Cypriniformes, like many other species-rich groups of vertebrates, has evolved over time with some consistency and inconsistencies of relationships across various studies. Within Cypriniformes, the Holarctic family Leuciscidae is one of the most widely distributed and hi...

The North American fish genus Macrhybopsis (Teleostei: Cyprinidae) as presently conceived comprises 12 species and occurs in much of interior eastern North America. Variation in the mitochondrial ND2 gene and the nuclear S7 intron 1 reveal conflicting gene-tree relationships for deeper nodes, which are assumed to represent past introgression and he...

The phylogeny of otocephalan fishes is the subject of broad controversy based on morphological and molecular evidence. The primary unresolved issue pertaining to this lineage relates to the origin of Characiphysi, especially the paraphyly of Characiformes. The considerable uncertainty associated with this lineage has precluded a greater understandi...

Fish species of the genus Capoeta are known for their special mouth morphology (inferior mouth with the horny edge to the lower jaw), short dorsal fin with seven to nine branched rays, and their tumultuous taxonomic history. The genus Capoeta has had a complex evolutionary history with high diversification in the Middle East and is closely related...

For many years the North American cyprinid fish Macrhybopsis aestivalis (common name: Speckled Chub) was regarded as a single widespread and morphologically variable species, occurring in rivers throughout much of the Mississippi Val-ley and geographically adjacent eastern Gulf slope drainages, west to the Rio Grande basin in Texas, New Mexico, and...

Gene choice, base compositional heterogeneity and rate heterogeneity are known to influence phylogenetic reconstruction but are often overlooked. Here, we investigate the impact of these factors in reconstructing the phylogenetic relationships and divergence times of cypriniform fishes. We compile a multilocus data set of newly sequenced and previo...

A new cyprinid fish, Hypselobarbus kushavali, is described from Kali River, Karnataka, India. Hypselobarbus kushavali is diagnosed from its closest congener, H. dobsoni, by having more upper transverse scale rows, more circumferential scale rows and more lateral line to pelvic scale rows, and from H. bicolor and H. jerdoni by having fewer lateral-l...

Garra fluviatilis is a new species described herein from the Kwai Noi, Mae Khlong basin, in the Thong Pha Phum District of Kanchanaburi Province in western Thailand. It is diagnosed by the following combination of morphological characters: well developed upper lip with unculiferous papillae, mottled pigmentation pattern, a pleated papilliferous fol...

Abstract Seven species of Garra are herein accounted for in Bhutan. Three new records of known species, G. arupi, G. birostris, and G. lissorhynchus, and two new species, G. bimaculacauda sp. nov. and G. parastenorhynchus sp. nov., are reported from central and southern Bhutan. Garra bimaculacauda sp. nov. is most notably different from its congene...

This study represents a phylogenetic analysis of Pimephales notatus, a widely distributed North American cyprinid fish species, using one mitochondrial (cytb) and two nuclear (S7 and Rag1) genes. Despite the broad geographic distribution of this species that includes independent basins, results suggest a largely drainage-independent genetic structu...

Identifying areas at risk of invasion can be difficult when the distribution of a non-native species encompasses geographically disjunct regions. Understanding genealogical relationships among native and non-native populations can clarify the origins of fragmented distributions, which in turn can clarify how fast and far a non-native species may sp...

Sisorid catfishes are primarily limited in distribution to rivers of the Himalayan region and Tibetan Plateau. These species have external morphologies that are adapted for extremely fast-flowing riverine systems. Given the diversity of the group and the above qualities of these catfishes, this lineage serves as an ideal group for inferring the geo...

Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review t...

Meristic and morphometric analyses and comparisons were conducted between an undescribed sucker of Río Culiacán (Catostomus sp.) and a Yaqui sucker (Catostomus bernardini) from the rivers Yaqui, Fuerte and Conchos in the Sierra Madre Occidental. A discriminant function analysis based on 44 characters (37 morphometric and 7 meristic) of 96 adult spe...

Phylogenetic relationships within Labeobarbus, the large-sized hexaploid cyprinids, were examined using cytochrome b gene sequences from a broad range of geographic localities and multiple taxa. Maximum likelihood and Bayesian methods revealed novel lineages from previously unsampled drainages in central (Congo River), eastern (Genale River) and so...

African diploid barbs (‘Barbus’, Clypeobarbus, Barboides, etc.) are a group of small cyprinids with a body size less than 20 cm and widely distributed in drainages across Africa. These species constitute a significant component of African freshwater fish fauna. This study is the first to focus on the molecular systematics and biogeography of Africa...

Hypselobarbus kurali (Menon & Rema Devi, 1995) consists of multiple species with similarity in the color pattern of the tip of their caudal fins being orange and black. This complex of species possesses two pairs of barbels. Inspection of collections of H. kurali from the senior author’s samples from various streams/rivers of Western Ghats covering...

This study represents a thorough analysis of Codoma, a monotypic genus endemic to north-western Mexico. A previous morphological analysis of the species concluded that there exists several morphological groups in Codoma ornata, suggesting diversity in Codoma could be underestimated. No studies have examined the genetic diversity in Codoma ornata to...

Salmonid fishes are cold water piscivores with a native distribution spanning nearly the entire temperate and subarctic northern hemisphere. Trout in the genus Oncorhynchus are the most widespread salmonid fishes and are among the most important fish species in the world, due to their extensive use in aquaculture and valuable fisheries. Trout that...

Garra robertsi is described from specimens collected from the Sungai Bongan and Tempassuk rivers in Sabah, Borneo. The species is differentiated from G. borneensis, its only congener on the island of Borneo, in having five (versus four) transverse scale rows above lateral line, the first branched dorsal-fin ray extending beyond the posterior-most e...

The cyprinid genus Pteronotropis is endemic to southeastern Gulf of Mexico and Atlantic Ocean of North America. Never before has the genus been demonstrated to be monophyletic. We investigate both the phylogenetic relationships and the phylogeography of some species in the genus using mitochondrial ND2 sequences. In no analysis is the genus resolve...

The genus Pteronotropis is widely distributed along the gulf slope of eastern North America from Louisiana to Florida and rivers in South Carolina along the Atlantic slope. Pteronotropis have very distinctive, flamboyant coloration. The habitats most frequently associated with these species include heavily vegetated backwater bayous to small sluggi...

Cyprininae is the largest subfamily (>1300 species) of the family Cyprinidae and contains more polyploid species (∼400) than any other group of fishes. We examined the phylogenetic relationships of the Cyprininae based on extensive taxon, geographical, and genomic sampling of the taxa, using both mitochondrial and nuclear genes to address the phylo...

The Acanthomorpha is the largest group of teleost fishes with about one third of extant vertebrate species. In the course of its evolution this lineage experienced several episodes of radiation, leading to a large number of descendant lineages differing profoundly in morphology, ecology, distribution and behavior. Although Acanthomorpha was recogni...

Sinocyclocheilus brevifinus sp. nov. is described from a subterranean river at Maohedong Village, Guangxi Zhuang Autonomous Region, Southern China. The new species can be distinguished from all congeners in having functional eyes, last simple dorsal fin ray soft and without serrations along posterior margin, eye diameter small (3.4-5.0 %SL), tip of...

The Mexican native trout complex is the group of salmonids that naturally has the southernmost distribu-tion in the world. Despite its unique status and evidence of more than 13 distinct lineages, there are only two described species (Oncorhynchus mykiss nelsoni and O. chrysogas-ter). These fishes are threatened by environmental and anthropogenic f...

Aim Any discovery of new biogeographical pattern in landlocked animals may challenge hypotheses that account for the evolution of intercontinental faunas. In this study, we examined the evolutionary origin and historical biogeography of temperate, freshwater perch‐like fishes within a molecular phylogenetic framework. Location Temperate Eastern Eu...

Evolutionary radiations, especially adaptive radiations, have been widely studied but mainly for recent events such as in cichlid fish or Anolis lizards. Here, we investigate the radiation of the subfamily Cyprininae, which includes more than 1300 species and is estimated to have originated from Southeast Asia around 55 Ma. In order to decipher a p...

Intense geological activity caused major topographic changes in Western North America over the past 15 million years. Major rivers here are composites of different ancient rivers, resulting in isolation and mixing episodes between river basins over time. This history influenced the diversification of most of the aquatic fauna. The genus Pantosteus...

We present seventeen microsatellite loci developed for the Mexican golden trout Oncorhynchus chrysogaster through GS-FLX 454 pyrosequencing. We selected 34 primer pairs tested on 19 trout specimens from The Rio Verde (Rio Fuerte Bain) and we tested cross amplification on 35 trout specimens collected in seven hydrological basins from the Sierra Madr...

In 2013, the seventh edition of the Common and Scientific Names of Fishes from the United States, Canada, and Mexico was published. Major changes include the capitalization of English common names, the addition of French common names for each species found in Canada, and the recognition of occurrences in the Arctic Ocean as separate from the Atlant...

The biogeography of the mega-diverse, freshwater, and globally distributed Otophysi has received considerable attention. This attraction largely stems from assumptions as to their ancient origin, the clade being almost exclusively freshwater, and their suitability as to explanations of trans-oceanic distributions. Despite multiple hypotheses explai...

Taxonomically exhaustive and continent wide patterns of genetic divergence within and between species have rarely been described and the underlying evolutionary causes shaping biodiversity distribution remain contentious. Here, we show that geographic patterns of intraspecific and interspecific genetic divergence among nearly all of the North Ameri...

Tree including all North American freshwater fish samples used in this study (5 674 specimens from 752 species). This dataset is described in detail by April and collaborators (2011). (DOCX)

List of species included in the intraspecific divergence analyses. (DOCX)

List of species included in the analyses testing the correlation between mass specific metabolic rate and mutation rate. (DOCX)

List of species included in the analyses testing the correlation between mtDNA divergence and nucDNA divergence Data from: Schönhuth S, Mayden RL (2010) Phylogenetic relationships in the genus Cyprinella (Actinopterygii: Cyprinidae) based on mitochondrial and nuclear gene sequences. Mol Phylo Evol 55∶77–98. (DOCX)

Results of generalized linear mixed models using a dataset that includes species sharing haplotypes. For the model testing the presence of a breakpoint at glacier margin, we conducted a piece-wise regression involving a break at 46° of latitude which corresponds to the maximal extent of Pleistocene glaciations events. (DOCX)

Pearson correlations between explanatory variables. (DOCX)

List of species included in the interspecific divergence analyses. (DOCX)

The cyprinid subfamily Oxygastrinae is composed of a diverse group of fishes that has been taxonomically and phyloge- netically problematic. Their great variation in appearance, life histories, and trophic diversity resulted in uncertainty re- garding their relationships, which led to their historical classification across many disparate subfamilie...

Olyra astrifera, a new species of Olyrid catfish is described from the Manimalai River of south Kerala in southern Western Ghats. It can be distinguished from its congeners (except O. horae) by its adipose fin confluent of with caudal base, pectoral fins with weak serrations and strong dentitions, a greater length of the adipose fin base, a shorter...

The cyprinid genus, Oxygaster van Hasselt, 1823, is the name-bearing type genus of the family-group name Oxygastri Bleeker, 1860, which predates many of the commonly used family-group names for the family Cyprinidae. Historically, the phylogenetic position of Oxygaster within the cyprinid phylogeny has been poorly understood, resulting in an uncert...

Abstract The Zebrafish, Danio rerio, is a well-known vertebrate model species widely used in research associated with biomedical areas and comparative and evolutionary biology. Interestingly, despite the importance of this species, little is known about the natural history, habitats, and native distribution. In our study of the species, we collecte...

The barbin genera Discherodontus Rainboth 1989, Chagunius Smith 1938 and Hypselobarbus Bleeker 1860 are distrib-uted in Southeast and South Asia and are among the least studied taxa of the order Cypriniformes. Few morphological studies have been conducted on these genera and only a very limited number of morphological characters were employed to hy...

The phylogenetic or evolutionary relationships of species of Cypriniformes, as well as their classification, is in a era of flux. For the first time ever, the Order, and constituent Families are being examined for relationships within a phylogenetic context. Relevant findings as to sister-group relationships are largely being inferred from analyses...

The order Cypriniformes and family Catostomidae, the Holarctic suckers, have received considerable phylogenetic attention in recent years. These studies have provided contrasting phylogenies and classifications to historical, morphology-based phylogenetic and prephylogenetic hypotheses of relationships of species and the naturalness of hypothesized...

Species of the nemacheilid genus Homatula are endemic to the Yunnan-Guizhou Plateau of China. Herein we provide phy-logenetic inferences of species relationships based on complete sequences of the mitochondrial cytochrome b gene (cyt b) and partial sequences of the nuclear recombination activation gene (RAG 1). Both gene trees (and the concatenated...

Borneo Island is governed by the countries of Brunei Darussalam, Malaysia (Sabah and Sarawak) and Indonesia (Kalimantan) and is part of Sundaland. These countries have a high diversity of freshwater fishes, especially described and undescribed species of Cypriniformes; together these species and other flora and fauna represent an extraordinary oppo...

The cyprinid tribe Labeonini (sensuRainboth, 1991) is a large group of freshwater fishes containing around 40 genera and 400 species. They are characterized by an amazing diversity of modifications to their lips and associated structures. In this study, a total of 34 genera and 142 species of putative members of this tribe, which represent most of...

Psilorhynchus pseudecheneis is redescribed based on examination of 120 specimens, 16-103 mm SL. It is distinguished from all congeners by its higher number of unbranched pectoral-fin rays and lateral-line scale rows, lower number of circumpeduncular scale rows, absence of scales from the dorsal midline between occiput and mid-point between occiput...

Members of the teleost superorder Ostariophysi dominate freshwater habitats on all continents except Antarctica and Australia. Obligate benthic and rheophilic taxa from four different orders of the Ostariophysi (Gonorynchiformes, Cypriniformes, Characiformes, and Siluriformes) frequently exhibit thickened pads of skin along the ventral surface of t...