Robert C. Schelly

Taxonomic Impediment or Impediment to Taxonomy? A Commentary on Systematics and the Cybertaxonomic-Automation Paradigm

Marcelo R. de Carvalho AE Flavio A. Bockmann AE Dalton S. Amorim AE Carlos Roberto F. Brandao AE Mario de Vivo AE Jose L. de Figueiredo AE Heraldo A. Britski AE Mario C. C. de Pinna AE Naercio A. Menezes AE Fernando P. L. Marques AE Nelson Papavero AE Eliana M. Cancello AE Jorge V. Crisci AE John D. McEachran AE Robert C. Schelly AE John G. Lundberg AE Anthony C. Gill AE Ralf Britz AE Quentin D. Wheeler AE Melanie L. J. Stiassny AE Lynne R. Parenti AE Larry M. Page AE Ward C. Wheeler AE Julian Faivovich AE Richard P. Vari AE Lance Grande AE Chris J. Humphries AE Rob DeSalle AE Malte C. Ebach AE Gareth J. Nelson

Evolutionary history of the Lake Tanganyika cichlid tribe Lamprologini (Teleostei: Perciformes) derived from mitochondrial and nuclear DNA data.

Lake Tanganyika comprises a cichlid species flock with substrate-breeding and mouthbrooding lineages. While sexual selection via mate choice on male mating color is thought to boost speciation rates in mouthbrooding cichlids, this is not the case in substrate-breeding lamprologines, which mostly form stable pairs and lack sexual dichromatism. We present a comprehensive reconstruction of the evolution of the cichlid tribe Lamprologini, based upon mtDNA sequences and multilocus nuclear DNA (AFLP) markers. Twelve mtDNA clades were identified, seven of which were corroborated by the AFLP tree. The radiation is likely to have started about 5.3 MYA, contemporarily with that of the mouthbrooding C-lineage, and probably triggered by the onset of deep-water conditions in Lake Tanganyika. Neither the Congo- nor the Malagarazi River species form the most ancestral branch. Several conflicts in the mtDNA phylogeny with taxonomic assignments based upon color, eco-morphology and behavior could be resolved and complemented by the AFLP analysis. Introgressive hybridization upon secondary contact seems to be the most likely cause for paraphyly of taxa due to mtDNA capture in species involving brood-care helpers, while accidental hybridization best explains the para- or polyphyly of several gastropod shell breeders. Taxonomic error or paraphyly due to the survival of ancestral lineages appear responsible for inconsistencies in the genera Lamprologus and Neolamprologus.

The Covert World of Fish Biofluorescence: A Phylogenetically Widespread and Phenotypically Variable Phenomenon

The discovery of fluorescent proteins has revolutionized experimental biology. Whereas the majority of fluorescent proteins have been identified from cnidarians, recently several fluorescent proteins have been isolated across the animal tree of life. Here we show that biofluorescence is not only phylogenetically widespread, but is also phenotypically variable across both cartilaginous and bony fishes, highlighting its evolutionary history and the possibility for discovery of numerous novel fluorescent proteins. Fish biofluorescence is especially common and morphologically variable in cryptically patterned coral-reef lineages. We identified 16 orders, 50 families, 105 genera, and more than 180 species of biofluorescent fishes. We have also reconstructed our current understanding of the phylogenetic distribution of biofluorescence for ray-finned fishes. The presence of yellow long-pass intraocular filters in many biofluorescent fish lineages and the substantive color vision capabilities of coral-reef fishes suggest that they are capable of detecting fluoresced light. We present species-specific emission patterns among closely related species, indicating that biofluorescence potentially functions in intraspecific communication and evidence that fluorescence can be used for camouflage. This research provides insight into the distribution, evolution, and phenotypic variability of biofluorescence in marine lineages and examines the role this variation may play.

Genetic isolation and morphological divergence mediated by high-energy rapids in two cichlid genera from the lower Congo rapids

BackgroundIt is hypothesized that one of the mechanisms promoting diversification in cichlid fishes in the African Great Lakes has been the well-documented pattern of philopatry along shoreline habitats leading to high levels of genetic isolation among populations. However lake habitats are not the only centers of cichlid biodiversity - certain African rivers also contain large numbers of narrowly endemic species. Patterns of isolation and divergence in these systems have tended to be overlooked and are not well understood.ResultsWe examined genetic and morphological divergence among populations of two narrowly endemic cichlid species, Teleogramma depressum and Lamprologus tigripictilis, from a 100 km stretch of the lower Congo River using both nDNA microsatellites and mtDNA markers along with coordinate-based morphological techniques. In L. tigripictilis, the strongest genetic break was concordant with measurable phenotypic divergence but no morphological disjunction was detected for T. depressum despite significant differentiation at mtDNA and nDNA microsatellite markers.ConclusionsThe genetic markers revealed patterns of philopatry and estimates of genetic isolation that are among the highest reported for any African cichlid species over a comparable geographic scale. We hypothesize that the high levels of philopatry observed are generated and maintained by the extreme hydrology of the lower Congo River.

Does counting species count as taxonomy? On misrepresenting systematics, yet again

Recent commentary by Costello and collaborators on the current state of the global taxonomic enterprise attempts to demonstrate that taxonomy is not in decline as feared by taxonomists, but rather is increasing by virtue of the rate at which new species are formally named. Having supported their views with data that clearly indicate as much, Costello et al. make recommendations to increase the rate of new species descriptions even more. However, their views appear to rely on the perception of species as static and numerically if not historically equivalent entities whose value lie in their roles as “metrics”. As such, their one‐dimensional portrayal of the discipline, as concerned solely with the creation of new species names, fails to take into account both the conceptual and epistemological foundations of systematics. We refute the end‐user view that taxonomy is on the rise simply because more new species are being described compared with earlier decades, and that, by implication, taxonomic practice is a formality whose pace can be streamlined without considerable resources, intellectual or otherwise. Rather, we defend the opposite viewpoint that professional taxonomy is in decline relative to the immediacy of the extinction crisis, and that this decline threatens not just the empirical science of phylogenetic systematics, but also the foundations of comparative biology on which other fields rely. The allocation of space in top‐ranked journals to propagate views such as those of Costello et al. lends superficial credence to the unsupportive mindset of many of those in charge of the institutional fate of taxonomy. We emphasize that taxonomy and the description of new species are dependent upon, and only make sense in light of, empirically based classifications that reflect evolutionary history; homology assessments are at the centre of these endeavours, such that the biological sciences cannot afford to have professional taxonomists sacrifice the comparative and historical depth of their hypotheses in order to accelerate new species descriptions.

Revision of the Congo River Lamprologus Schilthuis, 1891 (Teleostei: Cichlidae), with Descriptions of Two New Species

Abstract The Congo River Lamprologus are revised and two new species are described. Lamprologus teugelsi, n.sp., from Malebo Pool and the lower Congo River rapids, and L. tigripictilis, n.sp., from the lower Congo River rapids, are readily distinguished from the remaining Congo River Lamprologus based on counts, measurements, osteology, and color pattern. Monophyly of the Congo River Lamprologus species is tentatively accepted and a key to the group is provided. All available collection localities for re-identified Lamprologus material from the Congo River are plotted for each species. Maps of collection localities reveal large distributional voids, suggesting that Congo River lamprologine diversity remains incompletely sampled.

A New Species of Raiamas (Teleostei: Cyprinidae) from the Lower Congo River, with a Phylogenetic Assessment of the Generic Limits of the Predatory Cyprinid Genera Opsaridium, Raiamas, and Leptocypris

Abstract In the course of ongoing survey work in the lower Congo River, two collections of an undescribed species of the predatory cyprinid genus Raiamas have been made; one in the Congo main channel in the vicinity of Inga, and a second in the Inkisi River, a large south bank tributary of the Congo. Discovery of this new taxon has prompted a reexamination of potentially related taxa of adjacent regions and an attempt to provide generic diagnoses for the morphologically similar cyprinid genera Leptocypris, Raiamas, and Opsaridium. Based on a series of derived features of the neurocranium, pectoral girdle, jaws, and suspensorium, anatomical diagnoses for the three cyprinid genera are provided. We reassign Opsaridium christyi to Raiamas and Raiamas weeksii to Leptocypris. These two generic reassignments and the discovery of the new Raiamas bring the number of species of Raiamas confirmed from the lower Congo River to four: R. salmolucius, R. buchholzi, R. christyi, and the new species, R. kheeli, described herein. The reassignment of Opsaridium weeksii to Leptocypris raises the number of species of Leptocypris recorded from the region to four: L. modestus, L. lujae, L. weynsii, and L. weeksii.

A New Alestes (Characiformes, Alestidae) from the Mpozo River in the Democratic Republic of Congo

Abstract A new species of Alestes from the Mpozo River in the Bas Congo Province of the Democratic Republic of Congo is described and diagnostic characters for the genus are presented. Alestes inferus, new species, is differentiated from all other members of the genus by its lower and non-overlapping lateral-line scale count (31–33 versus 36–51) and its reduced and non-overlapping vertebral count (39–40 versus 41–49). Within Alestes, the new species appears to be most closely related to A. macrophthalmus and A. liebrechtsii, based on the shared possession by these three species of a tubular, bony extension enclosing the olfactory nerve on the lateral ethmoid, and bifurcated lateral-line canals terminating in two pores. Alestes liebrechtsii and A. inferus are the only species of the genus known from the lower Congo River.