Mário C. C. de Pinna

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

Species concepts and phylogenetics

Concepts of species proposed within the phylogenetic paradigm arecritically reviewed. Most so called ‘phylogenetic species concepts’ relyheavily on factors immaterial to phylogenetic hypotheses. Thus, theyhave limited empirical content and offer weak bases on which to makedecisions about real problems related to species. Any workable notion ofspecies relies on an explicit character analysis, rather than onabstract properties of lineages, narrative predications and speculationson tokogenetic relationships. Species only exist conjecturally, as thesmallest meaningful units for phylogenetic analysis, as based oncharacter evidence. Such an idea considers species to be conjecturesbased on similarity, that are subsequently subject to testing by theresults of analysis. Species, thus, are units of phylogenetic analysisin the same way as hypotheses of homology are units of comparablesimilarities, i.e. conjectures to be tested by congruence. Althoughmonophyly need not be demonstrated for species-level taxa, hypotheses ofrelationships are the only basis to refute species limits and guidenecessary rearrangements. The factor that leads to recognition ofspecies is similarity in observed traits. The concept of life cycle isintroduced as an important element in the discussion of species, as anefficient way to convey subsidiary notions of sexual dimorphism,polymorphism, polytypy and clusters of diagnosable semaphoronts. Thenotion of exemplars is used to expand the concept ofspecies-as-individual-organisms into a more generally usable concept.Species are therefore proposed for a diagnosable sample of(observed or inferred) life cycles represented by exemplars all of whichare hypothesized to attach to the same node in a cladogram, and whichare not structured into other similarly diagnosable clusters. Thisdefinition is character-based, potentially testable by reference to abranching diagram, and dispenses with reference to ancestor-descendantrelationships or regression into population concepts. It provides aworkable basis on which to proceed with phylogenetic analysis and abasis for that analysis to refute or refine species limits. A protocolis offered for testing hypotheses of species boundaries in cladograms.Concepts of species proposed within the phylogenetic paradigm arecritically reviewed. Most so called ‘phylogenetic species concepts’ relyheavily on factors immaterial to phylogenetic hypotheses. Thus, theyhave limited empirical content and offer weak bases on which to makedecisions about real problems related to species. Any workable notion ofspecies relies on an explicit character analysis, rather than onabstract properties of lineages, narrative predications and speculationson tokogenetic relationships. Species only exist conjecturally, as thesmallest meaningful units for phylogenetic analysis, as based oncharacter evidence. Such an idea considers species to be conjecturesbased on similarity, that are subsequently subject to testing by theresults of analysis. Species, thus, are units of phylogenetic analysisin the same way as hypotheses of homology are units of comparablesimilarities, i.e. conjectures to be tested by congruence. Althoughmonophyly need not be demonstrated for species-level taxa, hypotheses ofrelationships are the only basis to refute species limits and guidenecessary rearrangements. The factor that leads to recognition ofspecies is similarity in observed traits. The concept of life cycle isintroduced as an important element in the discussion of species, as anefficient way to convey subsidiary notions of sexual dimorphism,polymorphism, polytypy and clusters of diagnosable semaphoronts. Thenotion of exemplars is used to expand the concept ofspecies-as-individual-organisms into a more generally usable concept.Species are therefore proposed for a diagnosable sample of(observed or inferred) life cycles represented by exemplars all of whichare hypothesized to attach to the same node in a cladogram, and whichare not structured into other similarly diagnosable clusters. Thisdefinition is character-based, potentially testable by reference to abranching diagram, and dispenses with reference to ancestor-descendantrelationships or regression into population concepts. It provides aworkable basis on which to proceed with phylogenetic analysis and abasis for that analysis to refute or refine species limits. A protocolis offered for testing hypotheses of species boundaries in cladograms.

A new species of Glaphyropoma: the first subterranean copionodontine catfish and the first occurrence of opercular odontodes in the subfamily (Siluriformes: Trichomycteridae)

A new species of the rare copionodontine genus Glaphyropoma is described from subterranean waters in the Diamantina Plateau, Bahia State, central northeastern Brazil. This is the first troglomorphic species in the subfamily Copionodontinae. It is distinguished from all other copionodontines by the presence of opercular odontodes, and further distinguished from its only congener, G. rodriguesi, by the reduction of dark integumentary pigmentation. The new species shares the single synapomorphy previously proposed for Glaphyropoma, the marked narrowing of the first hypobranchial and indirect character evidence also supports its inclusion in the genus. The presence of opercular odontodes in the new species, in combination with a reviewed hypothesis of sister group relationship between Copionodontinae and Trichogeninae, indicate that the absence of opercular odontodes in previously-known copionodontines is secondary, rather than primitive.

The Neotropical whale catfishes (Siluriformes: Cetopsidae: Cetopsinae), a revisionary study

The catfishes of the subfamily Cetopsinae of the Neotropical family Cetopsidae are revised. Four genera, Cetopsidium new genus, Cetopsis, Denticetopsis, and Paracetopsis Bleeker are recognized as valid. Bathycetopsis, Hemicetopsis, and Pseudocetopsis are considered synonyms of Cetopsis and Paracetopsis Eigenmann & Bean and Cetopsogiton synonyms of Paracetopsis. Thirty-seven species are recognized in the Cetopsinae. Cetopsidium includes six species: C. ferreirai, new species, rio Trombetas; C. minutum, Essequibo River; C. morenoi, central and western portions of rio Orinoco; C. orientale, coastal rivers of Suriname and French Guiana, and tentatively rio Tocantins and rio Xingu; C. pemon, new species, rio Caura, rio Caroni, rio Meta, and rio Branco; and C. roae, new species, Rupununi River. Cetopsis includes 21 species: C. amphiloxa, rio San Juan, rio Atrato, and rio Patia, western Colombia, and rivers of northwestern Ecuador; C. arcana, new species, rio Tocantins; C. baudoensis, rio Baudo; C. caiapo, new species, rio Tocantins; C. candiru, Amazon basin; C. fimbriata, new species, rio Truando; C. coecutiens, rio Amazonas, rio Tocantins, and rio Orinoco; C. gobioides, upper rio Sao Francisco, rio Parana, rio Uruguay, and rio Juquia; C. jurubidae, rio Jurubida; C. montana, new species, western portions of Amazon basin; C. motatanensis, Lago Maracaibo basin; C. oliveirai, Amazon basin; C. orinoco, rio Orinoco, rio Aroa, and rio Yaracuy; C. othonops, rio Magdalena and rio Sinu; C. parma, western Amazon basin; C. pearsoni, new species, upper portions of rio Madeira; C. plumbea, western portions of rio Amazonas; C. sandrae, new species, rio Tapajos; C. sarcodes, new species, rio Tocantins; C. starnesi, new species, northwestern rio de La Plata and southern rio Madeira; and C. umbrosa, new species, western rio Orinoco. Cetopsis chalmersi is a synonym of C. gobioides. Cetopsis macroteronema is a synonym of C. plumbea. Denticetopsis includes seven species: D. epa, new species, rio Tocantins; D. iwokrama, new species, Siparuni River; D. macilenta, Potaro River; D. praecox, rio Baria; D. royeroi, upper rio Negro; D. sauli, upper rio Negro; and D. seducta, new species, western portions of rio Amazonas and rio Orinoco. Paracetopsis consists of three species: P. atahualpa, new species, rio Tumbes, northwestern Peru, and rio Zarumilla, southwestern Ecuador; P. bleekeri, rio Guayas and rio Santa Rosa, south-western Ecuador; and P. esmeraldas, new species, rivers of northwestern Ecuador. Cetopsis ventralis and C. occidentalis are synonyms of Paracetopsis bleekeri. A neotype is designated for Paracetopsis bleekeri. Lectotypes are designated for Cetopsis candiru, Cetopsis chalmersi, and Cetopsis plumbeus.

Description of a second species of the catfish †Hypsidoris and a reevaluation of the genus and the family †Hypsidoridae

ABSTRACT A second species of the genus †Hypsidoris is described from the primitive catfish family †Hypsidoridae. The new species is from Eocene freshwater deposits of the Clamo Formation of central Oregon and is known by numerous well-preserved skeletons. Like the type species from the Green River Formation of Wyoming, the Oregon species has a well-developed toothed maxilla, a feature thought to be primitive among catfishes. Among the more than 35 nominal families containing over 2,200 species of catfishes, only Diplomystidae and †Hypsidoridae have well-developed toothed maxillae. The relationships of †Hypsidoridae to other catfishes are briefly reviewed. The associated ichthyofauna is also briefly discussed in context with other Eocene faunas of western North America.

New and Noteworthy Venezuelan Glanapterygine Catfishes (Siluriformes, Trichomycteridae), with Discussion of Their Biogeography and Psammophily

Abstract Four new species of the trichomycterid subfamily Glanapteryginae are described from the Río Orinoco basin of Venezuela. Two new species each in Pygidianops Myers 1944 and Typhlobelus Myers 1944 represent the first documented occurrence of these genera in Venezuela, and for Pygidianops the first occurrence outside the Río Negro basin. The new species were captured from sand-bottom habitats in two disparate locations in the Orinoco River basin and display a remarkable suite of reductive features, such as loss of eyes, fins, and pigment, and reductions or absence of laterosensory canals and odontodes. Pygidianops cuao, n.sp. from the Río Cuao, a clear-water tributary of the upper Orinoco River, is diagnosed from its congeners by the presence of diminutive eyes and a triangular skin flap at the corner of the mouth. Pygidianops magoi, n.sp., known from near the delta of the Orinoco River, is diagnosed from its congeners by the absence of pectoral and anal fins, presence of four laterosensory pores, and nine or ten caudal-fin rays. Typhlobelus guacamaya, n.sp. from the Río Cuao is diagnosed relative to its congeners by the presence of three branchiostegal rays, posterior naris absent, lack of pleural ribs, and is further distinguished from both T. ternetzi and T. macromycterus by the absence of eyes and from T. lundbergi by the presence of three laterosensory canal pores. Typhlobelus lundbergi, n.sp. from the lower Orinoco is diagnosed by the presence of four laterosensory canal pores and further distinguished from T. ternetzi and T. macromycterus by the absence of eyes. We review the characters useful in diagnoses of Pygidianops and Typhlobelus among trichomycterid catfishes and discuss morphological patterns in the diversification of the Glanapteryginae. Species of Pygidianops and Typhlobelus are known only from the rivers draining the Guyana and Brazilian shields, yet within these areas they occupy all major water types. Such broad ecological range suggests that the geographic distribution of species of these two genera are not limited by water type. That observation, plus their common occurrence in the ubiquitous shallow sand-bottom habitats of the larger rivers of the shield regions of northern South America, indicate that species of Pygidianops and Typhlobelus may be expected to occur throughout the entire Amazon and Orinoco basins. The evolution of habitat preference in glanapterygines seems to follow a trend toward increased specialization for interstitial environments. The degree of psammophilic adaptation in species of Pygidianops and Typhlobelus is remarkable, without parallel in siluriforms and perhaps in any other freshwater fishes. We describe the physical characteristics of the sand and review the suite of morphological specializations for life in interstitial sand that are shared by these species, such as loss or reduction of certain structures and presence in these species of paired metapleural keels along the ventral edges of the abdomen formed by a long ridge of stiffened integument, underlain by well-differentiated medial infracarinalis muscles, that are superficially similar to the metapleural folds of sand-dwelling cephalochordates and other interstitial organisms.

Trichomycterus igobi, a new catfish species from the rio Iguaçu drainage: the largest head in Trichomycteridae (Siluriformes: Trichomycteridae)

A new species of Trichomycterus is described for the rio Iguacu drainage in Southern Brazil. Trichomycterus igobi, new species, is readily distinguishable from all other species currently in the genus by its extremely large head (23.8-26.8 % SL), which is proportionally the largest head in any Trichomycteridae. That characteristic plus the relatively deep body result in a very short-bodied overall aspect, the most extremely such case in the genus Trichomycterus. Other diagnostic features that distinguish the new species from most or all of its congeners include a short caudal peduncle (15.4-19.7 % SL); an almost entirely cartilaginous second hypobranchial (with only vestigial ossification); a mesial expanded palatine ossification; a narrow cleithrum, falciform in shape; and the lack of a proximal posterior concavity on the third ceratobranchial. The new species seems to form a monophyletic group with T. stawiarski and other undescribed species (T. sp. C), also endemic to the rio Iguacu. As putative synapomorphies, the three species share a rigid spine-like morphology of individual procurrent caudal-fin rays, an extended area of dorsal caudal-fin procurrent rays, and numerous branchiostegal rays (ten or eleven).

Phreatic Catfish of the Genus Silvinichthys from Southern South America (Teleostei, Siluriformes, Trichomycteridae)

Abstract Silvinichthys bortayro, new species, is described from an aquifer at 1200 m elevation in the Andean Cordillera of Salta, Argentina. The new species is distinguished from all other species included in the subfamily Trichomycterinae by the following combination of characters: the extreme elongation of the opercle and its narrow odontode-bearing distal section; the elongated and strongly curved coronoid process of the lower jaw; the absence of the pelvic fin and girdle; the pale integumentary pigmentation; and the reduction of the eyes. It differs further from Silvinichthys mendozensis, its only congener, by having six pectoral-fin rays and in the absence of the pelvic fin and girdle. Silvinichthys bortayro, nueva especie, es descripta de un acuífero de 1200 m de altura en la cordillera de los Andes de Salta, Argentina. La nueva especie se distingue de todas las otras especies incluidas en la subfamilia Trichomycterinae por la siguiente combinación de caracteres: el extremo alargamiento del opérculo y su estrecha sección distal de soporte de odontoides, el proceso coronoideo de la mandíbula inferior alargado y fuertemente curvado, la ausencia de la aleta y cintura pélvica, la clara pigmentación del tegumento, y la reducción de los ojos. Esta difiere además de Silvinichthys mendozensis, su único congénere, por tener 6 radios en la aleta pectoral y la ausencia de la aleta y cintura pélvica.

A New Species of the Neotropical Catfish Genus Trichomycterus (Siluriformes: Trichomycteridae) Representing a New Body Shape for the Family

Abstract Trichomycterus crassicaudatus is described as a new species from the Rio Iguaçu basin in southern Brazil. The new species has an exceptionally deep posterior region of the body (caudal peduncle depth 22.8–25.4% SL), resulting in an overall shape which distinguishes it at once from all other members of the Trichomycteridae. The caudal fin of the species is broad-based and forked, a shape also distinguishing it from all other species in the family. A number of autapomorphic modifications of T. crassicaudatus are associated with the deepening of the caudal region, including an elongation of the hemal and neural spines of the vertebrae at the middle of the caudal peduncle. Phylogenetic relationships of the new species are yet unresolved, but it shares a similar color pattern and a thickening of caudal-fin procurrent rays with T. stawiarski, a poorly-known species also from the Rio Iguaçu basin. Coloration and body shape also include similarities with T. lewi from Venezuela.

A new species of Trichogenes from the rio Itapemirim drainage, southeastern Brazil, with comments on the monophyly of the genus (Siluriformes: Trichomycteridae)

A new species of the formerly monotypic genus Trichogenes is described from a high-altitude stream of the rio Itapemirim system, an isolated Atlantic drainage in the State of Espirito Santo, southeastern Brazil. Trichogenes claviger, new species, differs from all other trichomycterids by the sexually dimorphic posterior process of the opercle, much elongated in males; the terminal mouth; the deeply bifurcated anterior neural spines and the presence of a large anterodorsal claw-like process on the neural arches of the anterior four free vertebrae. The new species also differs from its only congener, T. longipinnis, by a number of additional traits, including the the lack of branched anal-fin rays in specimens of any size; the broader than long posterior nostril; the deeper head (head depth 72.9-86.6% HL); the presence of a fine dark line along the base of the anal fin; the lack of dark spots on cheeks; the shape of the interopercle; the presence of odontodes on a bony expansion on the posterodorsal margin of the interopercle; the fewer vertebrae (35); the absence of an antorbital; and the fewer pleural ribs (eight). Small juveniles of the new species are also strikingly different from those of all other Trichomycteridae, including T. longipinnis, having a very large lateral eye, an upturned mouth, and compressed head. Trichogenes claviger occurs in shaded sectors of a blackwater sluggish stream with sandy substrate and patchy accumulations of vegetable debris, a habitat markedly different from the rocky torrential environment known for T. longipinnis. A comparison of the internal anatomy of the two species provides the basis for a hypothesis of a monophyletic Trichogenes. Data from the new species further support a sister-group relationship between Trichogeninae and Copionodontinae, as well as the position of that clade as sister group to all remaining Trichomycteridae.