Browsing by Author "Grande, Lance."
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Item Freshwater stingrays of the Green River Formation of Wyoming (early Eocene), with the description of a new genus and species and an analysis of its phylogenetic relationships (Chondrichthyes, Myliobatiformes). Bulletin of the AMNH ; no. 284(New York, NY : American Museum of Natural History, 2004) Carvalho, Marcelo R. de.; Maisey, John G.; Grande, Lance.Freshwater stingrays from the Fossil Butte Member of the late early Eocene Green River Formation of Wyoming are reviewed, and a new genus and species of fossil stingray is described. †Asterotrygon maloneyi, n.gen., n.sp. is remarkably well preserved and is known from articulated skeletons of juveniles and adults, both males and females. It is distinguished from all Recent and fossil stingrays, including †Heliobatis radians from the same formation, by the unique presence of a dorsal fin covered with dermal denticles directly anterior to the caudal stings. Other characters that in combination distinguish the new fossil genus from all other stingrays include: retention of separate, individual vertebrae extending to the tail extremity instead of a cartilaginous rod posterior to caudal stings; dorsal surface of disc and tail covered by numerous, closely packed, minute denticles; tail relatively stout at base; and relative proportions of disc and tail. †Asterotrygon, n.gen. shares with certain stingray genera postorbital processes of neurocranium separated from a supraorbital process by a small notch in the supraorbital shelf, presence of both dorsal and ventral tail-folds posterior to caudal stings (and internally supported by rudimentary radial elements), and hyomandibulae separated from lower jaws by a gap that originally contained the hyomandibular-Meckelian ligament. A calcified angular cartilage between the hyomandibula and Meckel's cartilage is tentatively identified in †Asterotrygon, n.gen. as well. †Asterotrygon, n.gen. is unquestionably a stingray, presenting many myliobatiform synapomorphies including caudal stings on the dorsal aspect of tail, lack of jugal arches in neurocranium, a thoracolumbar synarcual cartilage posterior to scapulocoracoid, absence of thoracic ribs, and laterally expanded, shelflike postorbital processes. †Asterotrygon, n.gen. and †Heliobatis primitively retain a narrow and slightly arched puboischiadic girdle and primitively lack calcified rostral elements in adults. A phylogenetic analysis of 23 stingray genera, two outgroups, and 44 informative morphological characters resulted in 35 equally most parsimonious trees. The strict consensus reveals the following hierarchical structure: Hexatrygon + (†Asterotrygon, n.gen., Plesiobatis, Urolophidae + (Urotrygonidae + (†Heliobatis + (Potamotrygonidae + (amphi-American Himantura, Pteroplatytrygon, Himantura, Taeniura, Dasyatis + (Gymnuridae + Myliobatidae)))))). Our resulting tree has nodes in common with previous phylogenetic analyses of stingrays (e.g., Hexatrygon is the most basal stingray genus; gymnurids and myliobatids (pelagic stingrays) are well-supported sister-groups), but includes novel components, such as a clade that includes all dasyatid genera (as a polytomy) and the component Gymnuridae + Myliobatidae. 'Dasyatidae' is not monophyletic in any of the minimum-length trees obtained; Urolophidae (Urolophus and Trygonoptera) and Urotrygonidae (Urobatis and Urotrygon) are both monophyletic, but are not sister-groups. †Asterotrygon, n.gen. forms a clade with urolophids in 21 of the 35 equally most parsimonious trees. Successive approximations weighting adds only one additional node in relation to the strict consensus, which unites Pteroplatytrygon, Dasyatis, and Himantura sensu stricto (in a polytomy) with Gymnuridae + Myliobatidae. The resulting stingray phylogeny is at odds with previous phylogenies mostly regarding the affinities of amphi-American Himantura and Taeniura, which do not form a monophyletic group with the South American freshwater stingrays (Potamotrygonidae) in any of the minimum-length trees obtained. Similar to most elasmobranch groups, stingrays display much character conflict, and cladogram topologies are very sensitive to changes in character coding. Due to a high degree of character variation present in certain generic-level terminal taxa, a more fully representative species-level phylogeny is necessary to clarify the systematic importance of tail-fold configuration, ceratobranchial fusion patterns, and other characters discussed in our study. Three additional synapomorphies of stingrays were uncovered by our study, pertaining to the configuration of the basihyal, first pair of hypobranchial cartilages, and to the forward extension of the basibranchial copula. Our phylogenetic results imply the following biogeographic patterns: the relationships of †Asterotrygon, n.gen. demonstrate a strong Indo-west Pacific historical correlation, while †Heliobatis displays an affinity with the Americas; the node containing the greatest diversity of modern stingrays ('Dasyatidae' + (Gymnuridae + Myliobatidae)) evolved only after an American stingray lineage was established sometime earlier than the early Eocene; and potamotrygonids date at least from the late early Eocene, and not the Miocene, as previous studies have implied. The mechanism responsible for the invasion of the potamotrygonid ancestor into South America could indeed have been a marine transgression as advocated by other authors, albeit a much earlier (pre-Miocene) one, during either the late Cretaceous or the late Paleocene to early Eocene.Item Interrelationships of fossil and recent anchovies (Teleostei, Engrauloidea) and description of a new species from the Miocene of Cyprus. American Museum novitates ; no. 2826(New York, N.Y. : American Museum of Natural History, 1985) Grande, Lance."Aside from species described only from otoliths, there are six alleged species of fossil anchovies (Engrauloidea). Of these only one (Engraulis macrocephalus from the Plio-Pleistocene of Italy) is recognizable as an anchovy on the basis of character information. Two are recognizable as clupeomorphs and probably as clupeids (aEngraulis longipinnis, Stolephorus lemoinei). Three are unrecognizable as clupeomorphs (lEngraulis evolans, E. brevipinnis, hEngraulites remifer). A new (and only the second valid) fossil species of anchovy, Engraulis tethensis n. sp. from the Upper Miocene of Cyprus, is the oldest known species of the group. The scarcity of fossil anchovies is anomalous in view of their abundance today (at least 130 species) and the abundance of fossil herrings (well over 100 species). Interrelationships of clupeomorph subgroups imply that anchovies (Engrauloidea) are as old as herrings (Clupeoidea). Ecology may explain the scarcity of fossil anchovies"--P. [1].Item Re-assessment of varanid evolution based on new data from Saniwa ensidens Leidy, 1870 (Squamata, Reptilia). American Museum novitates, no. 3630.(New York, NY : American Museum of Natural History, 2008) Conrad, Jack L.; Rieppel, Olivier.; Grande, Lance.Saniwa ensidens is a pivotal taxon for understanding varanid evolution. A complete specimen of Saniwa ensidens was recently described, offering important new insights into the morphology of this taxon. We apply these new data to a broader-scale study of squamate relationships in order to understand the phylogenetic position of Saniwa ensidens and of varanids more generally. Among the other fossils included in our analysis were the Eocene taxon "Saniwa" feisti, the Miocene Varanus rusingensis, and the giant Pleistocene varanid Megalania prisca. We compare the phylogenetic hypothesis from our analysis of morphology with a recent molecular-based hypothesis and find numerous differences in the phylogenetic relationships within Varanus. We constrained our morphological data set to the phylogenetic pattern presented by the molecular data to further analyze the possible phylogenetic relationships of the fossil taxa. Our analyses show that Saniwa ensidens is the sister taxon to crown-group Varanus and that "Saniwa" feisti is a basal member of the varanid lineage, not closely related to Saniwa ensidens. Both Varanus rusingensis and Megalania prisca are members of the crown radiations of Varanus.Item Recent and fossil clupeomorph fishes with materials for revision of the subgroups of clupeoids. Bulletin of the AMNH ; v. 181, article 2([New York] : American Museum of Natural History, 1985) Grande, Lance."The Clupeomorpha are a diverse, widespread group of fishes containing (as defined here) about 317 Recent and over 150 known fossil species. They are known as far back as the early Cretaceous and today are worldwide in distribution. Surprisingly little is known about this group phylogenetically. This study briefly reviews past work on clupeomorph interrelationships and examines the skeletal morphology of clupeomorphs to produce materials for a revision of the subgroups of clupeiform fishes. By concentrating on clupeomorph osteology, fossils can be added to the resulting classification. Comparative osteological data, based on examination of over 750 skeletal preparations, are summarized by 20 tables and several cladograms. The osteology of a pellonuline (Odaxothrissa vittata) and dorosomatine (Dorosoma cepedianum) is descriptively illustrated in detail. Also, a list of all nominal fossil species known to the author which appear to belong in Clupeomorpha as defined here, is provided (based on examination of either illustrations or specimens of over 150 fossil species), and the species in this list are briefly discussed. It was found that several skeletal characters define groups such as Clupeomorpha, Clupeomorpha Division 2, Clupeiformes, Clupeoidei, and some clupeoid subgroups. Based on osteological characters, the family Pristigasteridae should be excluded from the superfamily Clupeoidea (which includes Chirocentridae and Clupeidae); and the groups Pristigasteroidea, Engrauloidea, Clupeoidea, Clupeidae, Pellonulinae, and Dussumieriinae were each found to be monophyletic. Several fossil groups are removed from Clupeomorpha (†Ornategulum, †Clupavidae, †Engraulis evolans, and others). Cladograms for Pristigasteroidea, Dussumieriinae, and Pellonulinae are given based on osteological characters. No osteological characters were discovered to indicate that Dorosomatinae, Alosinae, Clupeinae, or these three groups together, are monophyletic. The biggest remaining problem in clupeomorph systematics is seen as discovering the interrelationships of the members of these three subfamilial 'groups of convenience' among Clupeoidei. It is hoped that this work will serve as a base for future phylogenetic studies on clupeomorph fishes by paleoichthyologists and neoichthyologists interested in clupeomorph osteology. The interrelationships of clupeid fishes and the placement of many fossil species within Clupeomorpha are still under study"--P. 235Item A revision of the fossil genus Diplomystus : with comments on the interrelationships of clupeomorph fishes. American Museum novitates ; no. 2728(New York, N.Y. : American Museum of Natural History, 1982) Grande, Lance.Several primitive clupeomorphs are described, and a hypothesis of clupeomorph interrelationships is proposed. The genus Diplomystus is revised and the type species for the genus, rD. dentatus Cope, 1877, is redescribed. Diplomystus dentatus is closely related to D. birdi Woodward, 1895, and D. dubertreti Signeux, 1951, and all three species form the sister group to sEllimmichthys longicostatus (Cope, 1886). Because the dorsal scutes of E. longicostatus lack the pectinate posterior border diagnostic of Diplomystus, Jordan's (1910 and 1919 (in Jordan and Gilbert, 1919)) removal of this species from Diplomystus is considered valid. Both tDiplomystus and Ellimmichthys are placed in lEllimmichthyidae, new family (Diplomystidae is preoccupied by a family of South American catfishes). The cEllimmichthyidae, new family, is the sister group to the Clupeiformes. Armigatus, new genus, is proposed for uClupea brevissimus Blainville, 1818. The relationship of Armigatus brevissimus, new genus, to other clupeomorphs is not clear, and it forms an unresolved trichotomy with cellimmichthyids and clupeiforms. Many other species erroneously assigned to the genus Diplomystus are removed to make the genus monophyletic and thus useful in systematic and comparative anatomical studies. The comparative morphology of clupeomorph dorsal scutes is discussed. It is found that 'double armor' in clupeiforms is not restricted to a small specialized group, but rather is a widespread character, occurring in clupeids, engraulids, "ellimmichthyids, and Armigatus. Detailed morphological study of the dorsal scute in clupeomorphs shows a complex of several characters. some of which can be used to define monophyletic groups within the Clupeomorpha"--P. [1].Item A revision of the fossil genus Knightia, with a description of a new genus from the Green River Formation (Teleostei, Clupeidae). American Museum novitates ; no. 2731(New York, N.Y. : American Museum of Natural History, 1982) Grande, Lance."The fossil genus Knightia is revised; bK. eocaena Jordan, 1907, and K. alta (Leidy, 1873) are redescribed, and sK. vetusta, new species, is described from the Middle Paleocene Tongue River Formation of southeastern Montana. Knightia is placed in the Pellonulinae. It was found that the known geologic range of aKnightia is Middle Paleocene to Middle Eocene and its geographic distribution appears to be western North American, or possibly Pacific continental (western United States and possibly China). Knightia is known only from deposits of probable freshwater origin. A new clupeid genus, pGosiutichthys, is described from early Middle Eocene deposits of the Green River Formation in Wyoming. Gosiutichthys parvus, new species, is a small herring that, unlike iKnightia (the other Green River clupeid), has two supramaxillary bones, thin transparent scales, and several other differentiating characters. The interrelationships of G. parvus with other clupeids are not known, but it is placed provisionally in the poorly defined subfamily Clupeinae. The presence of two supramaxillary bones prevents its placement in Pellonulinae as the subfamily is currently defined"--P. [1].