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Supplemental Material for 'First report of biofluorescence in Arctic snailfishes and rare occurrence of multiple fluorescent colors in a single species. (American Museum novitates, no. 3967)'
No full textSupplemental Material for 'First report of biofluorescence in Arctic snailfishes and rare occurrence of multiple fluorescent colors in a single species. (American Museum novitates, no. 3967)
Systematics of West African "giant" Ricinulei
Full text link68 pages : illustrations (2 color) ; 26 cm.The Ricinulei Thorell, 1876, or "hooded tick-spiders," are among the rarest and least studied arachnid orders. Ricinoides Ewing, 1929, the only Old World genus of extant ricinuleids, with 11 species described from tropical West Africa, is the most neglected of the three genera currently recognized. A lack of attention to the systematics of Ricinoides has created a disparity between its taxonomic diversity and that of the New World genera, Cryptocellus Westwood, 1874, and Pseudocellus Platnick, 1980, in which many new species have been described in recent decades. The present contribution provides a revised diagnosis of Ricinoides, which includes two new, putative synapomorphies for the genus and addresses the systematics and morphology of a group of West African species, which includes the world's largest ricinuleids and the type species of the genus. This group of nine species, referred to as the "giant" Ricinulei, shares a unique combination of characters, many of which appear to be unique to the group, and appears to be monophyletic. Four species of this group are redescribed, with revised diagnoses, based on reexamination of the type material: Ricinoi des afzelii (Thorell, 1892), from Sierra Leone; Ricinoides atewa Naskrecki, 2008, from Ghana; Ric inoides feae (Hansen, 1921), from Guinea-Bissau; and Ricinoides westermannii (Guérin-Méneville, 1838), from Togo. Five new species are described, raising the number of species in the genus to 16: Ricinoides eburneus, sp. nov., and Ricinoides taii, sp. nov., from Côte d'Ivoire; Ricinoides iita, sp. nov., from Nigeria; Ricinoides kakum, sp. nov., from Ghana; and Ricinoides nzerekorensis, sp. nov., from Guinea. Comparative illustrations of the adult morphology are presented for all nine species. The male copulatory apparatus is described and illustrated in detail, and new terminology and characters presented. The female spermathecae are described and illustrated for six species in which the females are known, representing the first illustrated comparison of these structures in African ricinuleids. Geographical distribution records are revised and updated for the different species, and their distributions mapped
Cranial morphology and phylogenetic relationships of Trigonostylops wortmani, an Eocene South American native ungulate (Bulletin of the American Museum of Natural History, no. 449)
No full text183 pages : illustrations (some color) ; 26 cm.In 1933 George G. Simpson described a remarkably complete skull of Trigonostylops, an Eocene South American native ungulate (SANU) whose relationships were, in his mind, quite uncertain. Although some authorities, such as Florentino Ameghino and William B. Scott, thought that a case could be made for regarding Trigonostylops as an astrapothere, Simpson took a different position, emphasizing what would now be regarded as autapomorphies. He pointed out a number of features of the skull of Trigonostylops that he thought were not represented in other major clades of SANUs, and regarded these as evidence of its phyletic uniqueness. Arguing that the lineage that Trigonostylops represented must have departed at an early point from lineages that gave rise to other SANU orders, Simpson reserved the possibility that Astrapotheriidae might still qualify (in modern terms) as its sister group. Even so, he argued that the next logical step was to place Trigonostylops and its few known allies in a separate order, Trigonostylopoidea, coordinate with Astrapotheria, Notoungulata, Litopterna, and Pyrotheria. Simpson's classification was not favored by most later authors, and in recent decades trigonostylopids have been almost universally assigned to Astrapotheria. However, his evaluation of the allegedly unique characters of Trigonostylops and its allies has never been systematically treated, which is the objective of this paper. Using computed tomography, the skull of Trigonostylops is compared, structure by structure, to a variety of representative SANUs as well as extant perissodactylans (which together comprise the clade Panperissodactyla) and the "condylarthran" Meniscotherium. In addition to placing Simpson's character evaluations in a comparative context, we also provide detailed assessments of many vascular and pneumatization-related feature of panperissodactylans never previously explored. Overall, we found that this new assessment strengthened the placement of Trigonostylops within a monophyletic group that includes Astrapotherium and Astraponotus, to the exclusion of other SANU clades. Although Trigonostylops cannot be considered as morphologically distinct or unusual as Simpson thought, our comparative and phylogenetic analyses have helped to generate a number of hypotheses about character evolution and function in SANUs that may now be fruitfully tested using other taxon combinations
Gravity Versus Magnetic Fields in Forming Molecular Clouds
No full textThis repository contains scripts and data for Figures 2-7 in the paper by Ibanez-Mejia, Mac Low, & Klessen (2021, Astrophys. J., submitted) entitled "Gravity Versus Magnetic Fields in Forming Molecular Clouds”
Four new species of “hooded tick-spiders” (Ricinulei, Ricinoididae) from South and Central America : with clarification of the identity of Cryptocellus leleupi Cooreman, 1976 (American Museum novitates, no. 3976)
Full text link35 pages : illustrations (some color), map ; 26 cm.The Ricinulei Thorell, 1876, or “hooded tick-spiders,” are among the least studied arachnid orders. Knowledge of ricinuleid diversity has been slow to accumulate because these arachnids are underrepresented in biological collections. Despite an increase in the pace of new species descriptions in recent decades, the species richness of the order probably remains vastly underestimated. Large areas in some of the world’s most biodiverse countries are without a single record for the order, hence new records invariably turn out to be new species. The present contribution describes four new species of the mostly South American genus Cryptocellus Westwood, 1874: Cryptocellus canutama, sp. nov., and Cryptocellus jamari, sp. nov., from Brazil; Cryptocellus islacolon, sp. nov., from Panama; and Cryptocellus macagual, sp. nov., from Colombia. Additionally, a new diagnosis and description are provided for Cryptocellus leleupi Cooreman, 1976, long considered a nomen dubium. The known locality records of the five species and their putative relatives are mapped. The present contribution raises the number of Cryptocellus species to 45 and the number of extant species of Ricinulei to 101
A revision of the genus Hermacha Simon, 1889 (Mygalomorphae: Entypesidae), in southern Africa with revalidation of Hermachola Hewitt, 1915, and Brachytheliscus Pocock, 1902. (American Museum novitates, no. 3977)
Full text link80 pages : color illustrations, map ; 26 cm.The southern African species of the mygalomorph spider genus Hermacha Simon, 1889, are revised. Eight species are redescribed: H. brevicauda Purcell, 1903; H. caudata Simon, 1889; H. evanescens Purcell, 1903; H. fulva Tucker, 1917; H. lanata Purcell, 1902; H. nigrispinosa Tucker, 1917; H. sericea Purcell, 1902; and H. tuckeri Raven, 1985. The female of H. sericea and the male of H. evanescens are described for the first time. Three new species are described: H. septemtrionalis, sp. nov., H. maraisae, sp. nov., and H. montana, sp. nov. On the basis of their genital morphology H. curvipes Purcell, 1902, and H. nigra Tucker, 1917, are considered incertae sedis. Pionothele capensis Zonstein, 2016, was found to be conspecific with H. brevicauda and is synonymized. The genera Brachytheliscus Pocock, 1902, and Hermachola Hewitt, 1915, are revalidated and redescribed. Hermacha capensis (Ausserer, 1871) and H. crudeni Hewitt, 1913, are transferred to Hermachola. Hermachola crudeni (Hewitt, 1913), originally described from a female, and Hermachola grahami Hewitt, 1915, originally described from a male, were found to be conspecific and synonymized. A new species, Hermachola lyleae, sp. nov., is also described. New morphological characters for the diagnoses of these genera and a dichotomous key for all species considered here are provided. Known distributions are mapped and, where available, ecological data are included. With the exception of H. caudata and H. mazoena Hewitt, 1915, all species are endemic to South Africa, but further survey work in neighboring countries is needed. This work substantially improves the taxonomy of this group of spiders and provides a foundation for further investigation of the diversity and relationships of species within the region
Two new Phenacogrammus (Characoidei; Alestidae) from the Ndzaa River (Mfimi-Lukenie basin) of central Africa, Democratic Republic of Congo (American Museum novitates, no. 3980)
Full text link22 pages : color illustrations, color map ; 26 cm.Two new Phenacogrammus are described from the Ndzaa River, a small left-bank tributary of the Mfimi-Lukenie River in the central Congo basin. They share with P. deheyni, a congener endemic to the Cuvette Centrale to the north, a prominent anterior expansion of the first pleural rib; a feature interpreted here as a synapomorphy diagnostic for this species assemblage. The two new species are readily differentiated from P. deheyni based on differences in pigmentation patterning, a lower number of scales in longitudinal series (26–28 vs. 29–33) and a longer head length (m. 24.9% SL vs. 21.7 and 23.2% SL). Phenacogrammus flexus, new species, is distinguished from all congeners in the possession of 6 (vs. 7) supraneural bones, and a characteristic zigzag pattern of black pigmentation along and below the midline extending from the posterior border of the opercle to the base of the caudal peduncle. While no unambiguous morphological autapomorphies have been located to diagnose P. concolor, new species, it is nonetheless readily distinguished from all congeners, except P. deheyni and P. flexus, in the possession of a prominent anterior expansion of the first pleural rib. It differs from both P. deheyni and P. flexus in the absence of a dominant pigmentation patterning over the flanks and caudal peduncle. Additionally, it differs from P. flexus in a shallower body depth (m. 24.9% vs. 27.0% SL) and in the possession of 7 (vs. 6) supraneurals. The three species exhibit extensive divergence in mt-COI sequence (P. flexus vs. P. concolor 10.2%–11%; P. flexus vs deheyni 12.9%–13.5%; P. concolor vs. deheyni 11.3%–12.9%). Furthermore, analysis of shape variation utilizing geometric morphometrics indicates that each species differs significantly in body shape
Supplemental Online Material for 'Petrology of the opaque assemblages in unequilibrated ordinary chondrites'.
No full textSupplemental Online Material for Alpert, et. al. Petrology of the opaque assemblages in unequilibrated ordinary chondrites, Meteoritics & Planetary Science, 56, Nr 2, 311–330 (2021) doi: 10.1111/maps.1361
Supplemental Material for 'Total-evidence phylogeny of the New World Polistes Lepeletier, 1836, paper wasps (Vespidae, Polistinae, Polistini). (American Museum novitates, no. 3973)'
No full textSupplemental Material for 'Total-evidence phylogeny of the New World Polistes Lepeletier, 1836, paper wasps (Vespidae, Polistinae, Polistini). (American Museum novitates, no. 3973)
Taxonomy of Pteronotus davyi incae
No full text23 pages : color illustrations, color map ; 26 cm.The subgenus Pteronotus (naked-backed bats) comprises three species, P. davyi, P. fulvus, and P. gymnonotus, which are distinguished from other members of the genus Pteronotus by wing membranes that are fused along the dorsal midline and by skulls with noticeably upturned rostrums. Pteronotus davyi currently includes two morphologically differentiated subspecies ecies, P. d. davyi and P. d. incae, with strikingly disjunct geographic ranges. Whereas the nominotypical form is found in Central America, the Caribbean coastal region of northern South America, and the Lesser Antilles, the subspecies P. d. incae is restricted to a small area in northwestern Peru; to date, the phylogenetic relationships of these nominal taxa have not been explored. In the present contribution, we employed analyses of mitochondrial gene sequences, morphometrics, and qualitative-morphological comparisons to provide new information on P. d. incae and place the taxon in a phylogenetic context. Our results suggest that the geographically disjunct populations of P. davyi are genetically very similar even though they are morphologically and ecologically distinct. Recognizing that speciation is a process with intermediate stages that merit formal recognition, we support the retention of incae as a valid subspecies of Pteronotus davyi