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Eremochaetidae in Burmese amber.
No full text29 pages : illustrations (some color) ; 26 cm.All 16 species of the family Eremochaetidae occur from the late Jurassic to the mid-Cretaceous of eastern and Central Asia. The first species in amber, and the latest occurrence of the family, was recently described as Zhenia xiai, from the mid-Cretaceous of Myanmar, ca. 100 Ma. New observations of a finely preserved specimen allow refinement of the morphological interpretations in the original description. The female of Zhenia, for example, has the distinctive piercing oviscapt of the superfamily Archisargoidea, formed from modified cerci (not tergites 8 and 9 as originally reported). The pretarsus of Zhenia bears an enormous empodial pad and pair of pulvillae, but the claws are highly vestigial (contra Zhang et al., 2016). The fly was almost certainly a parasitoid. A cladistic analysis of 26 binary-state characters and six continuously variable characters, using 47 exemplar Archisargoidea species from most genera and all four families, and five outgroup Brachycera, has very poor support for most clades but confirms the position of Zhenia in Eremochaetidae. Evidence on the relationships of Archisargoidea to other Brachycera is reviewed, and a close relationship to the Nemestrinoidea or Muscomorpha is best supported. A catalog of the species and some higher taxa of Archisargoidea is provided
Extended Digital Supplement for Abundance, Major Element Composition and Size of Components and Matrix in CV, CO and Acfer 094 Chondrites
No full textThese files supplement Ebel et al. (2016), a detailed exploration of the relative abundances, chemical compositions, and sizes of all types of chondrules, Ca-, Al-rich inclusions (CAI), amoeboid olivine aggregates (AOA) and matrix in CO and CV type carbonaceous chondrites. We use the collective term “inclusions” to describe all these components except matrix. These data include informational tables about the samples and mapping, x-ray emission element maps of Si, Mg, Ca, Al, Ti and Fe in each of the meteorite samples studied, derived data that allows image analysis of samples, and examples of software code used to perform image analysis. Element maps are 32-bit mosaics collected on the electron microprobe as described in the “Methods” section of Ebel et al. (2016). Maps “-xx.tif” are 8-bit masks that remove non-mapped portions of rectangular maps from consideration by software. Derived data based on outlining (segmentation) of inclusions includes maps “-GSclasts.tif” in which each type of inclusion has a different grayscale as per Tab-C of this supplement. Files “-IJdraw.tif” document the centers of mass of each segmented object, output from the ImageJ software (see reference in Ebel et al. 2016). Files “-IJresultsC.csv” (csv are comma-separated values in ASCII) tabulate the centers of mass (CofM) of each segmented object, output from the ImageJ software, and these CofM are manually corrected for CofM that fall in the matrix or mask, or in a nearby object.Files “-rgbTab.csv” list every inclusion, filtered for artifacts, with the Red-Green-Blue color combination of that inclusion in “-rgbClasts.tif”, and the minimum and maximum x and y of a bounding box around that inclusion. Other information includes the type of inclusion (originally assigned by inspection) and the computed area of each inclusion. With these data, it is possible to address rapidly and uniquely every pixel in any particular inclusion, and to then reference that pixel in all of the element maps. It is critical in this work that all the maps and derived mappings have identical x-y dimensions.
Data are arrange in four directories (folders): BSE holds back-scattered electron maps of all samples for which BSE were collected, RGB holds red-green-blue composites in Mg-Ca-Al, and Si-Ca-Fe, CO holds all maps and derived data for CO chondrites, and CV holds the same for the CV chondrites.
Five tables are provided, with captions in the table files. Tab-A lists samples, Tab-B reproduces Ebel et al. (2016) Table 8, Tab-C lists grayscale color equivalences used for “-GSclasts.tif”, Tab-D through Tab-F itemize all inclusions (see also “-rgbTab.csv” files) and the total element counts in each pixel in each inclusion, for CO, Allende and non-Allene CV chondrite samples, respectively. These data, with appropriate averaging and manipulation, are the basis for most of the figures and tabulated data presented in Ebel et al. (2015). Note that mapping conditions (dwell time and current) must be corrected among data sets to accurately compare element counts collected under different conditions.
A program written for IDL is provided, ClastCode-EbelEtal2015.pro (ASCII), that can be used to perform many of the image processing and analysis tasks described in the paper, using the digital data provided in this Extended Digital Supplement. This code is not guaranteed to work perfectly, however, it provides the basic algorithmic procedures used for much of the image analysis work reported
Morphological variation in a unisexual whiptail lizard (Aspidoscelis exsanguis) and one of its bisexual parental species (Aspidoscelis inornata) (Reptilia, Squamata, Teiidae) : is the clonal species less variable? (American Museum novitates, no. 3849)
No full text20 pages : 1 illustration ; 26 cm.Two clonal lineages, each comprising multiple generations of unisexual A. exsanguis, were produced in the laboratory from two lizards that were collected at the same locality in the field. Based on 10 meristic and four additional characters, we assessed morphological scores and relative variation as follows: (1) between the two laboratory lineages; (2) between these lineages pooled and samples of A. exsanguis and the bisexual (gonochoristic) A. inornata from the field; and (3) between field samples of the clonal lizards and A. inornata from a nearby locality. The two lineages differed significantly in the means and variances of two univariate characters and the two most informative multivariate characters. Contrary to expectations, the pooled sample of cloned laboratory lineages of A. exsanguis were as variable as the bisexual species in all 10 univariate characters and four important multivariate characters
New fossil bat from Hawaiʻi.
Get PDF52 pages : illustrations (some color), map ; 26 cm.Located over 3800 km from the nearest continent, the Hawaiian Islands have previously been thought to support only one endemic land mammal, the extant Hawaiian hoary bat (Lasiurus cinereus semotus), a taxon that apparently initially dispersed from mainland North America between 10,000 and 7000 years ago. Some uncertainty exists regarding the status of this taxon (i.e., whether or not populations representing more recent invasions of L. cinereus from North America are exchanging genes with the older lineage, and whether or not semotus represents a distinct species), but all researchers agree that hoary bats are the only endemic land mammals extant in the islands today. However, fossil evidence indicates that the Hawaiian Islands once supported another quite different endemic bat species that is now extinct. Skeletal remains of a new genus and species of vespertilionid bat are herein described from various Late Pleistocene and Holocene/Recent deposits on the five largest Hawaiian Islands. The new taxon is diagnosed by a mosaic of features including dental formula, molar morphology, skull shape, and metacarpal formula. This new taxon, which is smaller than Hawaiian hoary bat, was apparently present in the Hawaiian Islands by 320,000 years b.p. and survived until at least 1100 years ago and possibly much later. Accordingly, two species of bats coexisted on the Hawaiian Islands for several thousand years. As with numerous extinct endemic bird species, the extinction of the new bat taxon described here may have resulted either directly or indirectly from human colonization of the islands and the invasive nonnative species that came with human explorers and settlers
Cretaceous amber springtails.
No full text47 pages : illustrations (some color) ; 26 cm.Entomobryomorphan springtails (Hexapoda: Entognatha: Collembola) of the family Isotomidae are the most numerous group of Collembola in Spanish amber, a pattern typical in other studied Cretaceous amber deposits. Here we provide a revision of the Spanish amber springtail fauna, early Cretaceous (late Albian) in age, based on 93 specimens sufficiently well preserved to permit specific identification. Three new species are erected within the Isotomidae: Anurophorinae. These are: Burmisotoma spinulifera, new species, Protoisotoma autrigoniensis, new species, and Proisotoma communis, new species. The two former are respectively placed in the Cretaceous genera Burmisotoma Christiansen and Nascimbene (previously known from Cenomanian Burmese amber) and Protoisotoma Christiansen and Pike (in both Burmese and Canadian ambers), while the last species is indistinguishable from the extant, cosmopolitan genus Proisotoma Börner (also recorded in Burmese amber). Low morphological intraspecific variability is described for P. communis. Taxa are discussed in relation to other fossil entomobryomorphan lineages as well as their modern counterparts. A catalog of the known fossil springtails is appended. Isotomidae are diverse springtails, putatively basal among Entomobryomorpha and extending back into the early Devonian. Indeed, taxa described herein are overall remarkably similar to their extant relatives, emphasizing the antiquity and morphological stasis of the group as a whole
High resolution images for 'The anatomy and taxonomy of the exquisitely preserved Green River Formation (early Eocene) lithornithids (Aves) and the relationships of Lithornithidae. (Bulletin of the American Museum of Natural History, no. 406)'
No full textHigh resolution images for 'The anatomy and taxonomy of the exquisitely preserved Green River Formation (early Eocene) lithornithids (Aves) and the relationships of Lithornithidae. (Bulletin of the American Museum of Natural History, no. 406)' - http://hdl.handle.net/2246/666
New small barb from middle Congo basin.
No full text15 pages : illustrations (some color), color map ; 26 cm.A new species of smiliogastrin cyprinid is described from tributaries of the middle Congo River in the Democratic Republic of Congo. Restriction of the genus name, Barbus, to certain large-bodied, (polyploid) barbins, and current uncertainty regarding phylogenetic relationships among the numerous small-bodied African (diploid) barbs, renders generic assignment for the new species problematical. Pending the results of ongoing systematic analyses, and to reduce short-term nomenclatural instability, the new species is described here as a species of "Barbus." "Barbus" validus, new species, is readily distinguished from all other small-bodied African barbs by the combined possession of scales in midlateral series that are not enlarged relative to those along the impinging rows above and below; well-developed barbels, with the maxillary pair extending beyond the level of mideye, and the mandibular pair reaching the level of midopercle; the presence of numerous conical tubercles over the snout, cheek, and dorsum of head; a small circular occipital fontanel located medially at the parietal suture; well-developed gill rakers, with 8 or 9 on the hypo- and ceratobranchial elements of the first arch; a last unbranched dorsal-fin ray that is weakly ossified and lacking serrations along the posterior border; and a dorsal fin that is creamy white proximally and with the distal half to two thirds darkly pigmented
High resolution images for 'Taxonomic monograph of the endemic millipede assassin bug fauna of Madagascar (Hemiptera, Reduviidae, Ectrichodiinae). (Bulletin of the American Museum of Natural History, no. 400)'
No full textHigh resolution images for 'Taxonomic monograph of the endemic millipede assassin bug fauna of Madagascar (Hemiptera, Reduviidae, Ectrichodiinae). (Bulletin of the American Museum of Natural History, no. 400)' - http://hdl.handle.net/2246/664