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Dyrosaurid K/T survivorship.
No full text19 p. : ill., map ; 26 cm.
Includes bibliographical references (p. 15-17).We describe new dyrosaurid fossils from three localities in Mali, representing strata of Maastrichtian, Paleocene, and Eocene ages. The fossils significantly extend the temporal and geographic ranges of several known dyrosaurid taxa. Rhabdognathus keiniensis and Chenanisuchus lateroculi are identified for the first time from Maastrichtian sediments. Additional material is referred to Phosphatosaurus gavialoides and, tentatively, the genus Sokotosuchus. These discoveries represent the first occurrence of Chenanisuchus and possibly of Sokotosuchus from Mali. Previously unknown morphological character states are incorporated into existing data matrices, reducing the amount of missing data. Phylogenetic analyses largely corroborate prior hypotheses of dyrosaurid relationships, but indicate a need for new characters to resolve the relationships of certain genera and species. The occurrence of both basal (e.g., Chenanisuchus lateroculi) and highly nested (e.g., Rhabdognathus keiniensis) members of Dyrosauridae on both sides of the K/T boundary indicates that dyrosaurid diversification was well underway by the latest Cretaceous, and that most, if not all dyrosaurid species survived the extinction event. The geology of the Mali’s Tilemsi Valley is clarified; some rocks previously assigned to the Iullemmeden Basin actually represent extensions of other basins: the Taoudeni Basin and Gao Trench
First Asian spiders of the family Caponiidae (Araneae, Haplogynae).
Get PDF12 p. : ill. ; 26 cm.
Includes bibliographical references (p. 11-12).A new genus and species, Laoponia saetosa, are established to contain the first members of the family Caponiidae to be discovered in Asia. Only two Old World genera of caponiids have been described, both from Africa; in having only two eyes, the newly collected spiders from Laos resemble southern African Diploglena, rather than the type genus Caponia. However, members of Diploglena (which are poorly known, and are therefore discussed and illustrated) have an endite shape and eye pattern indicating that they may be most closely related to the Chilean genus Tisentnops. Laoponia may be most closely related instead to the endemic Californian genus Calponia; similar California/East Asia disjuncts are known in other old spider lineages
New species of Lithogenes.
No full text49 p. : ill. (some col.), map ; 26 cm.
Includes bibliographical references (p. 47-49).A new species of the loricariid genus Lithogenes Eigenmann, 1909, is described on the basis of 84 specimens captured from a single locality in the upper Río Orinoco drainage of southern Venezuela. The new species is only the third representative of the subfamily Lithogeninae to be recognized in the 100 years since the discovery of the type species, L. villosus, and is the only lithogenine known from more than a handful of specimens. This new material provides the basis for a comprehensive review of lithogenine systematics, comparative anatomy, and interrelationships. Lithogenes wahari, new species, shares with its congeners the dermal plates of the trunk comprised of three paired series, presence of a bifurcate levator arcus palatini crest and expanded lateral lamina of the hyomandibula, and the palatine sesamoid not reaching the nasal capsule, thus confirming its placement in Lithogenes among the Loricariidae. The new species is diagnosed among congeners by the absence of odontodes on the proximal portion of the ventral surface of the first pelvic-fin ray (vs. ventral pad covered with embedded odontodes along entire length) and thickened skin of the pelvic pad forming extensive ridges; accessory premaxillary teeth absent; anal fin with intense pigment band along base and diffuse spot at midlength of fin rays (vs. pigment band at base absent, fin rays dusky, without distinct spot). Characters useful for distinguishing lithogenine species are reviewed; revised diagnoses and descriptions are provided for the two previously described species in light of new character evidence. A detailed comparative analysis of the osteology and myology of L. wahari is presented and discussed relative to homologous conditions observed more broadly among the loricarioid catfishes. Of particular importance are aspects of musculoskeletal anatomy that are hitherto unknown for lithogenines, and aspects of sexual dimorphism and the anatomy of the reproductive and digestive systems that are unique or unusual among loricariid catfishes. A phylogenetic analysis of relationships among species based on morphological characters places the two Guyana Shield species (L. villosus and L.wahari) as sister taxa on the basis of four synapomorphies. Both species share reduction in the width and extent of the jaws, resulting in the derived reduction in the numbers of teeth carried by the jaw elements. Evaluated with respect to the geographic distribution of the species, the pattern of phylogenetic relationships suggests an ancestral widespread distribution for the Lithogeninae throughout the Guyana Shield plus the Caribbean and eastern Andean foreland basin of northern South America, followed by vicariance and subsequent divergence of populations now isolated in the coastal mountains of northern Venezuela and the Guyana Shield region. Lithogenine catfishes share a number of unique features with astroblepid catfishes that are not observed to occur in other members of the Loricariidae, such as the morphology of the pelvic fins, specialized pelvic musculature, and associated adaptations for climbing. Evaluated against the evidence supporting their phylogenetic placement as the sister group to all other Loricariidae, exclusive of the Astroblepidae, these shared similarities suggest that the association with rocky habitats of headwater stream systems and the ability to climb vertical surfaces may represent ancestral conditions for the lineage leading to the astroblepid plus loricariid catfishes
Earwig families
No full text20 p. ; 26 cm.Includes bibliographical references (p. 14-19).Family-group names for all taxa of earwigs (living and extinct) are listed with dates and sources indicated; in total 85 entries are recorded along with a single entry of dubious taxonomic identity (i.e., Ocelliidae, nomen dubium, a name apparently applied to a fossil earwig nymph of uncertain status and identity). This survey revealed two instances in which currently accepted names must be changed owing to priority by an older name: Platylabiinae and Cosmiellinae must be replaced by Palicinae and Skendylinae, respectively, as the family-group names remain valid despite synonymy of their type genera. The type genus of Verhoeff's Gonolabididae (as Gonolabidae) is Gonolabis, not Gonolabina (which is the type genus of Gonolabininae, Gonolabiinae auctorum) as asserted by various authors. In addition, the generally asserted authorship and dates of numerous names are found to be incorrect and are therefore revised herein. Most notably, the name Carcinophorinae as used by Hincks was a nomen nudum and therefore unavailable (the name was first made available by Popham). The widely employed spellings (all incorrectly formed) of Anataelinae, Challinae, Protolabinae, Anophthalmolabiinae, Titanolabinae, Gonolabinae, Brachylabinae, Isolabinae, Antisolabinae, Parisolabinae, Chaetospanini, Irdexinae, Eudohrninae, Rudraxinae, Gonolabinae, Rhyacolabinae, and Kinellinae are corrected to Anataeliinae, Challiinae, Protolabidinae (= Echinosomatinae), Anophthalmolabidinae, Titanolabidinae, Gonolabidinae (= Anisolabidinae), Brachylabidinae, Isolabidinae, Antisolabidinae, Parisolabidinae, Chaetospaniini, Irdicinae (= Spongophorinae), Eudohrniinae (= Neolobophorinae), Rudracinae, Gonolabininae, Rhyacolabidinae (= Ancistrogastrinae), and Kinesinae, respectively. The following nomenclatural changes are proposed: Acrania, reinstated as genus; Epicranopygia, new synonym of Acrania; Acrania angulata, new combination; A. constricta, new combination; A. eximia, reinstated combination; A. fletcheri, new combination; A. picta, reinstated combination; A. triangulata, new combination; A. vittipennis, new combination; Pyge, reinstated as genus; Paracranopygia, new synonym of Pyge; Pyge assamensis, new combination; P. bakeri, new combination; P. burmensis, new combination; P. comata, new combination; P. formosa, new combination; P. maculipes, new combination; P. meghalayana, new combination; P. modesta, reinstated combination; P. pallidipennis, new combination; P. proxima, new combination; P. semenovi, new combination; P. siamensis, new combination; P. similis, new combination; P. tonkinensis, new combination; P. variegata, new combination; P. vicina, new combination; Paradiplatys, reinstated as genus; Lobodiplatys, Heterodiplatys, and Epidiplatys, reduced to subgenera of Paradiplatys (and their included species reinstated in combination with Paradiplatys); Paradiplatys (Lobodiplatys) coriaceus, reinstated combination; P. (Paradiplatys) conradti, reinstated combination; P. (P.) lamottei, reinstated combination; P. (P.) pectinatus, reinstated combination; P. (P.) salvazae, reinstated combination; P. (P.) spinulosus, reinstated combination; P. (Heterodiplatys) bicolor, reinstated combination; P. (H.) bihamatus, reinstated combination; P. (H.) burri, reinstated combination; P. (H.) rotundicollis, reinstated combination; P. (H.) schoutedeni, reinstated combination; P. (Epidiplatys) gladiator, reinstated combination; Cretolabiinae, new subfamily (Anisolabididae); Paratitanolabis, new synonym of Titanolabis; Titanolabis bormansi, new combination; and Titanolabis myanmarensis, new name
On Cepheia longiseta
No full text18 p. : ill. ; 26 cm.Includes bibliographical references (p. 17-18).We redescribe the monotypic spider genus Cepheia and provide detailed morphological information on its type species, Cepheia longiseta. We provide the first exhaustive diagnosis for the genus, including for the first time detailed information about its external morphology as well as its tracheal system. Some morphological features previously proposed as synapomorphies for the Synaphridae are also present in Cepheia, which corroborates some of the diagnostic characters of the family. We also propose new synapomorphies for Synaphridae
Archaeological survey, Barinas
Get PDF343 p. : ill., maps (1 col.) ; 26 cm.Includes bibliographical references (p. 338-343)."This is the first of a series of monographs about an archaeological project that the authors carried out in the high llanos and Andean piedmont of the Distrito Pedraza, Barinas, Venezuela. We were interested in documenting the evolution of prehistoric chiefdoms in the western Venezuelan llanos and in assessing the possibility that intersocietal interaction such as exchange and warfare played a role in chiefdom development here. We benefited from reading the early historic accounts of the European explorers and missionaries who encountered chiefdoms in the western Venezuelan llanos in the sixteenth century. Also, we wanted to build on the findings of a few archaeologists who had conducted archaeological investigations in the western Venezuelan llanos to answer questions of chronology, settlement, and subsistence. Our research design called for monitoring prehistoric cultural developments in a study region centered on the Canagua River valley, extending across the high llanos and up into the adjacent piedmont, wherein we would collect archaeological data on regional settlement patterns, community organization, households and subsistence practices, and artifact distributions within and between settlements. In this volume, we present the Barinas project's research design, introduce the chronological sequences that we established for the Andean piedmont and high llanos, and report the findings of the first phase of field investigations: the five seasons of regional survey we conducted in our 450 km2 study region centered on the Canagua River valley. The bulk of this volume is devoted to detailed descriptions of 103 archaeological sites. Sites of the Curbati complex dated to A.D. 300-1000 are restricted to the piedmont, where they are typically located on remnant river terraces overlooking stretches of farmable alluvium. Our survey revealed evidence of a two-level settlement-size hierarchy for Curbati-complex sites in the Curbati and upper Canagua River valleys. While Curbati-complex sites never have earthworks, some Curbati-complex sites in the Curbati River valley are associated with petroglyphs. One of these sites was La Esmeralda (B8), the largest Curbati-complex settlement, which extended over 8 ha of an alluvial terrace on which stood a large boulder bearing petroglyphs. A similar two-level settlement-size hierarchy obtained for sites in the piedmont of the later Cano Seco complex, dated to A.D. 1000-1550, although there is evidence of population growth in the number and areal extent ([< or = to] 25 ha) of Cano Seco settlements, especially in the upper Canagua River valley. The only Cano Seco-complex site associated with petroglyphs, however, was the small (3.125 ha) site of La Piedra Herrada (B20) in the Curbati River valley. All but one of the petroglyphs discovered in our study region were confined to the Curbati River valley. Sites with Gavan-complex ceramics dated to A.D. 300-1000 are largely restricted to the high llanos, where our survey revealed a clear regional hierarchy of three levels according to site size and associated mounded architecture. The 33 ha site of El Gavan (B12), with its linear plaza flanked by tall earthen mounds, house mounds, and associated earthworks and causeways stood at the top of the settlement hierarchy. Linked by causeway to the regional center were five second-order settlements with similar mound configurations, only on a smaller scale. The lowest level of the regional settlement hierarchy consisted of 28 habitation sites smaller than 5 ha in area and without visible mounded architecture. We located, mapped, and test-excavated a 35 ha drained-fields facility (B27) southeast of the regional center of El Gavan; another expanse of drained fields may have existed northwest of the regional center at site B52 on the fertile alluvium of the Cano Mitiao Hondo. We estimate that the potential maize yields reaped on these drained fields would have greatly exceeded the subsistence requirements of the nearest habitation sites (B26, B98). Due to the drained fields' proximity to causeways leading to the regional center, we propose that the considerable agricultural surplus produced on the drained fields was delivered to the regional elite at El Gavan (B12). The discovery of four third-order habitation sites with Gavan-complex ceramics in the upper Canagua River valley, associated with large tracts of fertile alluvium, raises questions about the relationship and intersocietal interaction between the inhabitants of the high llanos and the adjacent forested piedmont in late Gavan times. The oval causeway that encloses the regional center of El Gavan may have served in part as a defensive earthwork. The degree of centralized regional organization manifested by the Gavan-complex settlement hierarchy, with the array of mounded architecture, the network of intersite causeways, and the implementation of drained-field agriculture, are commensurate with the archaeological manifestations expected for chiefly societies. The paramount chiefdom centered at El Gavan (B12) did not persist until the European incursions in the sixteenth century. We located eight Cano Seco-complex (ca. A.D. 1000-1550) sites on the high llanos, which adhered to the two-level settlement-size hierarchy obtained for Cano Seco-complex sites in the adjacent piedmont. We also located 10 sites of the early historic period on the high llanos that we assigned to the Chuponal complex and tentatively date to A.D. 1550-1850. The largest and greatest density of Chuponal settlements occurred on the El Chuponal alluvium, east and across the Canagua River from the town of Pedraza (Ciudad Bolivia), which was founded in 1591"--P. 10-11
The chiropteran premaxilla : a reanalysis of morphological variation and its phylogenetic interpretation ; American Museum novitates, no. 3585
No full text44 p. : ill. ; 26 cm.Includes bibliographical references (p. 42-44).The mammalian premaxilla, which bears the incisor teeth, is composed of a body and two processes (nasal and palatine) that articulate with other rostral bones via four cranial sutures. In bats, the premaxilla is modified in many ways, and this variation has been extensively used in bat systematics. The premaxilla has provided characters to diagnose a number of important taxonomic groupings--most notably, the division of Microchiroptera into the infraorders Yinochiroptera and Yangochiroptera. Recent molecular studies have challenged the monophyly of Microchiroptera, and several families have been transferred to clades other than those in which they were placed traditionally. Because premaxillary characters have figured prominently among those used to establish the traditional classification of bats, we compared the anatomy of the bone across suprageneric bat groups and provide revised descriptions of its variation. On the basis of extensive material examined, we generated 16 new characters, of which at least 12 are partially applicable to all Chiroptera, and several of which are informative within specific bat groups. Three new characters code variation in the basic structure of the chiropteran premaxilla in a new way. As a result, the traditional character defining Yinochiroptera (a "movable premaxilla") was found to lack an anatomical basis; by contrast, Yangochiroptera was still supported. Still, a tree search using just the new premaxillary characters recovered Yinochiroptera as monophyletic. Even with a low character-to-taxon ratio, premaxillary characters recover a number of clades recognized in recent phylogenetic studies of bats. Mapping of characters onto the latest molecular and morphological chiropteran trees required many more extra steps in the former than in the latter. Our interpretation of premaxillary variation in bats suggests two opposing trends in different lineages: one toward weakening and eventual loss of the bone, and the other toward a strengthening via suture fusion. We conclude that, despite some homoplasy, the chiropteran premaxilla is richer in potentially phylogenetically informative characters than previously thought and that it should be explored further in systematic studies of bats at a variety of systematic levels
Phylogeny of Pseudopolybia wasps
No full text11 p. : ill. ; 26 cm.Includes bibliographical references (p. 10-11).The male genitalia of Pseudopolybia vespiceps are described and compared to congeners. Characters of the male genitalia are combined with morphological characters of the females and nests and used in a phylogenetic analysis. The single cladogram resulting supports monophyly of the genus Pseudopolybia and interrelationships among the species as: P. langi + (P. difficilis + (P. compressa + P. vespiceps)). A new, illustrated identification key is presented
Revision of ponyfish Nuchequula
No full text25 p. : ill. (1 col.) ; 26 cm.Includes bibliographical references (p. 23-25).Nuchequula Whitley 1932, previously considered a subgenus of Leiognathus Lacep‡ede 1802, is elevated to generic rank. Nuchequula is diagnosed by the presence of a distinct saddle-shaped nuchal marking and by the presence of a pigment-free, mitten-shaped region posteroventral to the pectoral-fin base. The genus comprises five species, N. blochii, N. pan, N. nuchalis, N. decora, and a new species described herein. Nuchequula mannusella, new species, is distinguished from its congeners by a unique pigmentation pattern on the dorsal fin and morphology of the lower jaw. Redescriptions are provided for the other species. A phylogenetic analysis based on morphological characters, including features of the light-organ system, indicates that Nuchequula is monophyletic
Braincase in Paleozoic sharks
No full text122 p. : ill. (some col.) ; 26 cm.Includes bibliographical references (p. 116-122).The concepts of platytrabia/platybasia and tropibasia/tropitrabia in gnathostomes are reviewed. The terms platytrabia and tropitrabia refer to developmental states of the embryonic trabecular cartilages that can be determined only by ontogenetic studies. The terms platybasia and tropibasia originally had this meaning, but have subsequently taken on additional descriptive connotations involving morphological features in the prechordal part of the adult chondrocranium. However, platybasia and tropibasia are not synonymous with platytrabia and tropitrabia. In gnathostomes, platytrabia usually gives rise to a platybasic adult condition (but not invariably; e.g., Lepisosteus), and tropitrabia usually gives rise to the tropibasic condition (modern elasmobranchs may be an exception). Thus, ontogeny does not provide an absolute guide to the adult condition, nor does adult morphology provide an accurate means to assess the prior ontogenetic condition in gnathostomes. Platybasia and tropibasia are regarded here as useful morphological terms that can be applied to fossils or to extant forms for which ontogenetic data are not available (although it may still be possible to reach some ontogenetic conclusions, based on morphological observations). A well-preserved but disarticulated fossil symmoriiform shark braincase from the Pennsylvanian of Arkansas is described under the informal generic designation "Cobelodus", using digital reconstructions made from a high-resolution computerized-tomography (CT) scan. The braincase is morphologically tropibasic and clearly represents a departure from the common platybasic pattern found in elasmobranchs (e.g., Tamiobatis, Cladodoides, Orthacanthus). The contribution made by the embryonic polar cartilage in "Cobelodus" was probably extensive (unlike in modern gnathostomes), as in the platybasic Paleozoic shark Cladodoides. Thus, tropibasia in "Cobelodus" seems to be superimposed on an already-specialized pattern of cranial morphology found in some early platybasic elasmobranchs. The basicranial arterial circuit in "Cobelodus" was highly modified, and its internal carotids could not have communicated with the cranial cavity via the bucco-hypophyseal chamber as in other elasmobranchs. Internal carotids either were absent or met the efferent pseudobranchials within the orbit before the combined vessel entered the cranial cavity via the orbital cartilage, but the arrangement was certainly not osteichthyan-like (where the combined internal carotid/efferent pseudobranchial arteries pass through the basisphenoid pillar). "Cobelodus" and many other Paleozoic sharks possessed a postorbital palatoquadrate articulation (possibly strengthened by ligaments above the articulation in "Cobelodus"), on cartilage presumably formed in the embryonic lateral commissure. This arrangement differs from that in amphistylic hexanchiform sharks, where the lateral commissure is absent and there is no postorbital arcade; the postorbital articulation is located instead on the primary postorbital process (an outgrowth of the supraorbital shelf). Hexanchiforms are the only extant elasmobranchs with a postorbital articulation, but do not occupy a basal position in modern morphological and molecular phylogenetic analyses. Amphistyly in hexanchiforms is therefore viewed as a derived state rather than a highly conserved feature. No hyomandibular facet has been identified in "Cobelodus", suggesting that its epihyal had only a ligamentous connection to the braincase. However, previous suggestions that symmoriiforms were aphetohyoidean (with a complete hyoidean gill slit and "unmodified" hyoid arch) are not supported by morphological evidence. The systematic classification of symmoriiform sharks is in disarray. Symmoriiforms collectively are probably monophyletic, but within them only the family Falcatidae is characterized convincingly by synapomorphies. Remaining symmoriiforms have been traditionally classified as "stethacanthids" and "symmoriids", based respectively on the presence or absence of a spine-brush complex, but that distinction seems artificial because no undisputable "brushless male symmoriids" or "brushed female stethacanthids" have been documented and because sex-linked dimorphism of the spine-brush complex has been demonstrated only in falcatids. The braincase in Cladoselache shares some unusual features with "Cobelodus", suggesting that Cladoselache and symmoriiforms are closely related, but it has yet to be determined whether Cladoselache was morphologically platybasic or tropibasic