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Argentine fossorial mammal Necrolestes
No full text40 p. : ill. ; 26 cm.Includes bibliographical references (p. 37-40).We present new descriptions, figures, and interpretations of well-preserved cranioskeletal elements of the early Miocene, fossorial mammal Necrolestes patagonensis from Argentina. As previously noted, this animal is highly apomorphic and its phylogenetic affinities are difficult to interpret. Its derived features include hypsodont upper cheek teeth, a partially fused cervical spine, an unfused atlas consisting of separate right and left massae, and a distally ossified flexor tendon of the forearm. Characters that support its status as a therian mammal include a coiled cochlear housing of the inner ear. Consistent with its status as a metatherian is the presence of five upper incisors, transverse canal foramina, and a broad proximal fibula. However, we cannot confirm other characters claimed by previous researchers as evidence for affinity with marsupial or nonplacental mammals, such as the presence of an inflected mandibular angle and epipubic bones. Furthermore, Necrolestes shows similarities to eutherian mammals, such as small incisive foramina and possibly three molars. On biogeographic and some anatomical grounds, identification of Necrolestes as a metatherian remains a compelling option. However, pending a combined-data phylogenetic analysis encompassing Theria and accounting for the anatomical diversity of Necrolestes, possible membership in Eutheria should not be ruled out
Dental formulae in megabats
No full text27 p. : ill. ; 26 cm.Includes bibliographical references (p. 26-27).Variation in dental formulae observed in megachiropteran bats poses element homology problems. Identity of individual teeth has been controversial, with authors differing in their assessment of individual tooth homology, particularly with respect to incisors and premolars, in several taxa. Also, newly described taxa exhibit dental formulae whose implications for tooth homology have been little discussed. We compared crown morphology, tooth replacement, and dental anomalies in representatives of all megachiropteran genera. Our observations confirm the generalized megachiropteran dental formula (34 teeth represented by I1, I2, C, P1, P3, P4, M1, M2, i1, i2, c, p1, p3, p4, m1, m2, and m3) and establishes the homology of each tooth in most megachiropteran taxa in which reduction in tooth number has taken place. Some of our conclusions confirm presumed homologies postulated by previous authors, but in other cases new homology assignments are proposed. Uncorroborated assignments are reduced to just two taxa, Harpyionycteris and Nyctimeninae, both of which remain problematic with respect to homologies of the incisor dentition. Mapping tooth presence/absence on previously published phylogenetic trees reveals modest levels of ambiguity and homoplasy in patterns of tooth reduction in Pteropodidae, and indicates that reversals involving the reappearance of an ancestrally lost tooth may have taken place. Our results are consistent with dental field theory, which explains both reversals and anomalies as a regulatory variation that does not affect element homology because the latter is supported by structural genes
New scelionid wasp
No full text7 p. : ill. ; 26 cm.Includes bibliographical references (p. 6-7).Janzenella, new genus, is described from the Neotropics (type species: J. innupta, new species). The position of the genus within the superfamily is unclear. Janzenella is characterized by the strongly depressed body, relatively dorsal position of the foramen magnum of the head, and the loosely articulated metasomatic segments with broad laterotergites and no laterosternites
Cretaceous juvenile birds from China
No full text46 p. : ill. (some col.), map ; 26 cm.Includes bibliographical references (p. 41-46).Mesozoic remains of embryonic and early juvenile birds are rare. To date, a handful of in ovo embryos and early juveniles of enantiornithines from the early Cretaceous of China and Spain and the late Cretaceous of Mongolia and Argentina have comprised the entire published record of perinatal ontogenetic stages of Mesozoic birds. We report on the skeletal morphology of three nearly complete early juvenile avians from the renowned early Cretaceous Yixian Formation of Liaoning Province in northeastern China. Evidence of the immaturity of these specimens is expressed in the intense grooving and pitting of the periosteal surfaces, the disproportionately small size of the sterna, and the relative size of the skull and orbits. Size notwithstanding, anatomical differences between these three specimens are minimal, leaving no basis for discriminating them into separate taxa. Numerous osteological synapomorphies indicate that they are euenantiornithine birds, the most diverse clade of Enantiornithes, but their identification as members of a particular euenantiornithine taxon remains unclear. Their early ontogenetic stage, however, provides important information about the postnatal development of this specious clade of Cretaceous birds. The presence of pennaceous wing feathers suggests that fledging occurred very early in ontogeny, thus supporting a precocial or highly precocial strategy for enantiornithine hatchlings. The morphology of these new early-stage juveniles is also significant in that they allow a better understanding of the homologies of several avian compound bones because the components of these skeletal compounds are preserved prior to their coossification. The general morphology of the wrist and ankle of these juveniles highlights once again the striking similarity between nonavian theropods and early birds
Spider genus Myrmekiaphila.
No full text30 p. : ill. (some col.), maps ; 26 cm.Includes bibliographical references (p. 30).The mygalomorph spider genus Myrmekiaphila comprises 11 species known only from the southeastern United States. The type species, M. foliata Atkinson, is removed from the synonymy of M. fluviatilis (Hentz) and placed as a senior synonym of M. atkinsoni Simon. A neotype is designated for M. fluviatilis and males of the species are described for the first time. Aptostichus flavipes Petrunkevitch is transferred to Myrmekiaphila. Six new species are described: M. coreyi and M. minuta from Florida, M. neilyoungi from Alabama, M. jenkinsi from Tennessee and Kentucky, and M. millerae and M. howelli from Mississippi
Archaeoscelio and related genera
No full text24 p. : ill. ; 26 cm.Includes bibliographical references (p. 23-24).Four genera--Archaeoscelio Brues; Cobaloscelio Johnson and Masner, new genus; Plaumannion Masner and Johnson, new genus; and Huddlestonium Polaszek and Johnson, new genus--lack laterotergites and laterosternites in the metasoma, one of the synapomorphies of the superfamily Platygastroidea. The Baltic amber species Archaeoscelio rugosus Brues and Archaeoscelio filicornis Brues are diagnosed and figured, and two species from Baltic amber are described in Cobaloscelio - C. cuspidatus Johnson and Masner, new species and C. speculifer Johnson and Masner, new species. Plaumannion fritzi Masner and Johnson, new species (Brazil) and Plaumannion yepezi Garciá, new species (Venezuela) are described. Huddlestonium exu Polaszek and Johnson, new species is described from São Tomé and the Ivory Coast. The wing venation of Scelionidae is reinterpreted, and the marginal vein of Scelionidae and Chalcidoidea is considered to be a convergent feature
Thyreus gynandromorph (Apidae)
No full text11 p. : ill. ; 26 cm.Includes bibliographical references (p. 11).A lateral gynandromorph of Thyreus redactulus? Cockerell is described and figured, with a particular emphasis on the genitalic sclerites. As such, the sting morphology and mechanism are described for T. ramosus (Lepeletier de Saint Fargeau) to provide a comparative framework for understanding the gynandromorph. The implications of the gynandromorph's genitalic arrangements for intersexual homologies are explored
Introduction to Marine Conservation Biology (Lessons in Conservation, v. I, pp. 5-43)
No full text40 p.This document is specifically about those aspects of marine
biology that are used in marine conservation. It is not intended
to be a complete primer on marine conservation, which
incorporates other sciences (most notably the social sciences)
as well as traditional knowledge. To learn more about other
aspects of marine conservation, please refer to the following
marine modules: Marine Conservation Policy, Marine Protected
Areas and MPA Networks, and International Treaties for Marine
Conservation and Management, all of which complement this
module
Austro-Papuan Orthotylinae
No full text17 p. : ill. (some col.) ; 26 cm.Includes bibliographical references (p. 17).Sagittacopula, new genus, is described to accomodate S. rufescens, new species, from Cape York Peninsula, and S. carvalhoi, new species, from eastern New Guinea. Morobea Carvalho and its type species, Morobea longipes Carvalho, are redescribed, and M. spectabilis, new species, from eastern New Guinea is described. Wumea Carvalho and its type species, Wumea cylpealis Carvalho, are redescribed, and W. cassisi, new species, from eastern New Guinea is described