Weigt, L.A.

Abstract:

A new species of Rypticus is described from the Bahamas, Bermuda, Florida, and the Caribbean Sea. The species previously has been confused with the spotted soapfish, R. subbifrenatus Gill 1861, with which it shares a similar pattern of dark spotting on the body. The new species differs from R. subbifrenatus in having yellow pigment on the pectoral fin and distal portions of the soft dorsal, caudal, and anal fins in life (pale in preservative); a different configuration of dark spots on the head; usually dark spots on the belly and caudal fin; almost always four dorsal-fin spines; and modally 25 total dorsal-fin elements, 15 pectoral-fin rays, and 23 total caudal-fin rays. The lower jaw typically extends further anteriorly beyond the upper jaw in the new species than in R. subbifrenatus, and the caudal peduncle is usually narrower. The new Rypticus typically inhabits deeper waters than R. subbifrenatus, and is commonly found on vertical slopes and walls vs. shallow, flat areas. The new species likely would have continued to go unnoticed without examination of genetic data, as there was little reason to look further at R. subbifrenatus until DNA barcoding revealed two distinct genetic lineages within the species. The value of DNA barcoding data in systematic studies and the need for increased support of taxonomy are highlighted. A neotype for Rypticus subbifrenatus is designated. 

Abstract:

Species identification of western Atlantic Coryphopterus can be problematic because some of the species are morphologically similar, there is confusing morphological variation within some species, no taxonomic key includes all currently recognized species, and the validity of some species is questionable. The most recently published keys do not include Coryphopterus tortugae or C. venezuelae, the validity of which as distinct from C. glaucofraenum has been questioned. Neighbor-joining trees derived from mitochondrial cytochrome c oxidase I (COI) sequences (DNA barcoding) were used to determine the number of genetically distinct lineages of Coryphopterus from collections made off Belize, Curacao, and Florida. Additional specimens for genetic and morphological analysis were obtained from Panama, Venezuela, and the Bahamas. Subsequent comparative analysis of preserved voucher specimens from which DNA was extracted and digital color photographs of those specimens taken before preservation yielded, in most cases, sufficient morphological information to separate the genetic lineages. Species identification of the lineages was then determined based on review of original and subsequent descriptions of Coryphopterus species and examination of museum specimens, including some type material. Many museum specimens are misidentified. Twelve species of Coryphopterus are herein recognized in the western Atlantic and Caribbean: C. alloides, C. dicrus, C. eidolon, C. glaucofraenum, C. hyalinus, C. kuna, C. lipernes, C. personatus, C. punctipectophorus, C. thrix, C. tortugae, and C. venezuelae. Coryphopterus bol Victor, 2008 is a synonym of C. venezuelae (Cervigón, 1966). Although genetically distinct, C. glaucofraenum and some specimens of C. venezuelae are extremely similar and cannot be separated on the basis of morphology 100% of the time. Comments on the identification of each Coryphopterus species and a revised key to western Atlantic species are provided. 

Abstract:

Specimens of Starksia were collected throughout the western Atlantic, and a 650-bp portion of the mitochondrial gene cytochrome oxidase-c subunit I (COl) was sequenced as part of a re-analysis of species diversity of western Central Atlantic shorefishes. A neighbor-joining tree constructed from the sequence data suggests the existence of several cryptic species. Voucher specimens from each genetically distinct lineage and color photographs of vouchers taken prior to dissection and preservation were examined for diagnostic morphological characters. The results suggest that S. atlantica, S. lepicoelia, and S. sluiteri are species complexes, and each comprises three or more species. Seven new species are described. DNA data usually support morphological features, but some incongruence between genetic and morphological data exists. Genetic lineages are only recognized as species if supported by morphology. Genetic lineages within western Atlantic Starksia generally correspond to geography, such that members of each species complex have a very restricted geographical distribution. Increasing geographical coverage of sampling locations will almost certainly increase the number of Starksia species and species complexes recognized in the west- ern Atlantic. Combining molecular and morphological investigations is bringing clarity to the taxonomy of many genera of morphologically similar fishes and increasing the number of currently recognized species. Future phylogenetic studies should help resolve species relationships and shed light on patterns of speciation in western Atlantic Starksia. 

Bathygobius is currently represented by three species in the western Atlantic (B. soporator, B. curacao and B. mystacium) based on diagnostic morphological features. Our combined genetic and morphological analyses indicate that there are at least six species of Bathygobius comprising eight genetic lineages in the western Atlantic. Two lineages are identified as B. curacao and B. mystacium. Four lineages possess char- acters that would previously have led to their identification as B. soporator. Two of those are morphologically indistin- guishable and are recognized here tentatively as a single species, B. soporator. A third “B. soporator” lineage is dis- tinct, and Gobius lacertus is resurrected here as Bathygobius lacertus for that lineage. The fourth “B. soporator” lineage is also distinct and is described as a new species. Two other closely related genetic lineages are morphologically indis- tinguishable and are treated as a single new species. Redescriptions of B. soporator, B. mystacium and B. curacao are provided. Comments are made on the identification of larval Bathygobius from Belize.