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Caudal cranium of Sparassodonta.
Full text link64 pages : illustrations (some color) ; 26 cm.The caudal cranium of the South American sabertooth Thylacosmilus atrox (Thylacosmilidae, Sparassodonta, Metatheria) is described in detail, with emphasis on the constitution of the walls of the middle ear, cranial vasculature, and major nerve pathways. With the aid of micro-CT scanning of the holotype and paratype, we have established that five cranial elements (squamosal, alisphenoid, exoccipital, petrosal, and ectotympanic) and their various outgrowths participate in the tympanic floor and roof of this species. Thylacosmilus possessed a U-shaped ectotympanic that was evidently situated on the medial margin of the external acoustic meatus. The bulla itself is exclusively composed of the tympanic process of the exoccipital and rostral and caudal tympanic processes of the squamosal. Contrary to previous reports, neither the alisphenoid nor the petrosal participate in the actual tympanic floor, although they do contribute to the roof. In these regards Thylacosmilus is distinctly different from other borhyaenoids, in which the tympanic floor was largely membranous (e.g., Borhyaena) and lacked an enlarged ectotympanic (e.g., Paraborhyaena). In some respects Thylacosmilus is more similar to hathliacynids than to borhyaenoids, in that the former also possessed large caudal outgrowths of the squamosal and exoccipital that were clearly tympanic processes rather than simply attachment sites for muscles. However, hathliacynids also exhibited a large alisphenoid tympanic process, a floor component that is absent in Thylacosmilus. Habitual head posture was inferred on the basis of inner ear features. Large paratympanic spaces invade all of the elements participating in bounding the middle ear, another distinctive difference of Thylacosmilus compared to other sparassodonts. Arterial and venous vascular organization is relatively conservative in this species, although some vascular trackways could not have been securely identified without the availability of CT scanning. The anatomical correlates of the internal carotid in relation to other basicranial structures, the absence of a functional arteria diploetica magna, and the network for venous return from the endocranium agree with conditions in other sparassodonts
Short-tailed whipscorpion genus Stenochrus.
Full text link91 pages : illustrations, maps ; 26 cm.The short-tailed whipscorpion genus, Stenochrus Chamberlin, 1922 (Schizomida: Hubbardiidae Cook, 1899), occurring in North and Central America, is redefined and revised based on simultaneous phylogenetic analysis of 61 morphological characters and 2968 aligned DNA nucleotides from two markers in the nuclear genome, the internal transcribed spacer (ITS) and 28S rDNA, and two markers in the mitochondrial genome, cytochome c oxidase subunit I (COI) and 12S rDNA, for a comprehensive taxon sample. Six new genera are described: Ambulantactus, gen. nov.; Baalrog, gen. nov.; Harveyus, gen. nov.; Nahual, gen. nov.; Schizophyxia, gen. nov.; Troglostenochrus, gen. nov. Heteroschizomus Rowland, 1973, stat. rev., is revalidated and its type species, Heteroschizomus goodnightorum Rowland, 1973, reinstated. Six new species are described: Ambulantactus aquismon, sp. nov.; Ambulantactus montielae, sp. nov.; Baalrog yacato, sp. nov.; Harveyus contrerasi, sp. nov.; Heteroschizomus kekchi, sp. nov.; Nahual bokmai, sp. nov. Eighteen new combinations are created by transferring species, previously accommodated in Stenochrus, to other genera: Ambulantactus davisi (Gertsch, 1940), comb. nov.; Baalrog magico (Monjaraz-Ruedas and Francke, 2018), comb. nov.; Baalrog sbordonii (Brignoli, 1973), comb. nov.; Harveyus mexicanus (Rowland, 1971a), comb. nov.; Harveyus mulaiki (Gertsch, 1940), comb. nov.; Harveyus reddelli (Rowland, 1971a), comb. nov.; Heteroschizomus meambar (Armas and Víquez, 2010), comb. nov.; Heteroschizomus orthoplax (Rowland, 1973a), comb. nov.; Heteroschizomus silvino (Rowland and Reddell, 1977), comb. nov.; Nahual caballero (Monjaraz-Ruedas and Francke, 2018), comb. nov.; Nahual lanceolatus (Rowland, 1975), comb. nov.; Nahual pallidus (Rowland, 1975), comb. nov.; Pacal moisii (Rowland, 1973), comb. nov.; Pacal tepezcuintle (Armas and Cruz-López, 2009), comb. nov.; Schizophyxia bartolo (Rowland, 1973), comb. nov.; Schizophyxia lukensi (Rowland, 1973), comb. nov.; Troglostenochrus palaciosi (Reddell and Cokendolpher, 1986), comb. nov.; Troglostenochrus valdezi (Monjaraz-Ruedas, 2012), comb. nov. The male of B. sbordonii is determined to be heterospecific with the holotype female and described as B. yacato. The females of H. goodnightorum and N. lanceolatus are described for the first time. Following these revisions, seven species remain within Stenochrus: Stenochrus alcalai Monjaraz-Ruedas and Francke, 2018; Stenochrus chimalapas Monjaraz-Ruedas and Francke, 2018; Stenochrus gruta Monjaraz-Ruedas and Francke, 2018; Stenochrus guatemalensis (Chamberlin, 1922); Stenochrus leon Armas, 1995; Stenochrus pecki (Rowland, 1973); Stenochrus portoricensis Chamberlin, 1922. Olmecazomus, nom. nov., is proposed as a replacement name for the junior homonym, Olmeca Monjaraz-Ruedas and Francke, 2017, creating three new combinations: Olmecazomus brujo (Monjaraz-Ruedas and Francke, 2017), comb. nov.; Olmecazomus cruzlopezi (Monjaraz-Ruedas and Francke, 2017), comb. nov.; Olmecazomus santibanezi (Monjaraz-Ruedas and Francke, 2017), comb. nov. A key to identification of the hubbardiid genera of North America is provided and the utility of various character systems for the diagnosis of schizomid genera discussed. The integration of morphological and molecular data not only increased knowledge of the schizomid diversity in the New World but disentangled what was once considered a homoplastic and variable morphology in a large "catch-all" genus into discrete units each diagnosable by unique character combinations
New species of Cerambycinae and Lamiinae (Cerambycidae, Coleoptera) from Mexico. (American Museum novitates, no. 3938)
No full text13 pages : color illustrations ; 26 cm.Four new species of longhorn beetles (Cerambycidae, Coleoptera) from Mexico are described herein. Three are in the subfamily Cerambycinae: Aphysotes santossilvai, sp. nov., from Veracruz (new country record for the genus), Methia martinsi, sp. nov., from Oaxaca, and Corynellus lutescens, sp. nov., from Veracruz. The fourth is in the subfamily Lamiinae: Zikanita monnei, sp. nov., from Chiapas (also a new country record for the genus). All four species are illustrated with dorsal, ventral, lateral, and frontal views
New mormoopid bat from the Oligocene of Florida.
No full text141 pages : illustrations, maps ; 26 cm.A new genus and species of fossil bat, Koopmanycteris palaeomormoops, representing an ancient member of the endemic Neotropical family Mormoopidae, is described from the Oligocene of Florida. This new species is known from two paleokarst deposits in northern peninsular Florida, the early Oligocene (Whitneyan, 30-32 Ma) I-75 Local Fauna in Alachua County and the late Oligocene (early Arikareean, 26-28 Ma) Brooksville 2 Local Fauna in Hernando County. The discovery of Koopmanycteris extends the fossil record of the Mormoopidae back in time almost 30 million years. Compared to most other described taxa of North American Tertiary bats, the fossil sample of Koopmanycteris palaeomormoops is substantial, consisting of 50 specimens including: P4, all lower teeth from p3 through m3, dentary, petrosal, humerus, proximal radius, and femur. Koopmanycteris is morphologically intermediate between the two living genera of mormoopids, Mormoops and Pteronotus, but is most similar to the former taxon. Characters shared by Koopmanycteris and Mormoops include: large anterolabial basin on P4; large, double-rooted p3; secondary process ventral to angular process on dentary; absence of groove separating capitulum into medial and lateral portions on distal humerus; presence of prominent ridge on posterolateral edge of distal humeral shaft; rounded extremity on proximal radius; and presence of a prominent ridge or tubercle on posterodistal shaft of femur. All of these features appear to be relatively derived, with the exception of the large, double-rooted p3. In several mandibular characters, Koopmanycteris more closely resembles Pteronotus, including: pronounced posteroventral process on the symphysis; lack of curvature of ventral edge of horizontal ramus between posterior edge of symphysis and p4; and less pronounced dorsal upturning of ascending ramus compared to Mormoops. Koopmanycteris retains the primitive dental morphology of Mormoops, with a large double-rooted p3, and the primitive posterior mandibular morphology of Pteronotus, with the lesser degree of dorsal flexion of the ascending ramus. A phylogenetic analysis including all known extant mormoopid lineages as well as representative outgroups from other noctilionoid clades confirms that Koopmanycteris and Mormoops are sister taxa. These findings indicate that the lineages leading to Pteronotus and Mormoops were distinct by ~30 Ma. The fossil record tentatively indicates that the Mormoopidae originated in North America in the early Oligocene or earlier, and may not have reached South America until the Pliocene following the onset of the Great American Biotic Interchange. Several lines of evidence support this hypothesis: (1) the earliest fossil record of the Mormoopidae is in the early Oligocene of Florida; (2) the greatest diversity and endemism of modern mormoopid species is in the West Indies; and (3) the absence of a pre-late Pleistocene record, lack of endemism, and marginal recent distribution of mormoopids in South America. Most species of living mormoopids are obligate cave dwellers, suggesting that the occurrence of caves and paleokarst deposits has affected both their modern distribution and fossil record
Nesting biology of the bee Caupolicana yarrowi.
Full text link20 pages : illustrations (some color), color maps ; 26 cm.
Appendix: Use of nectar by the desert bee Caupolicana yarrowi (Colletidae) in cell construction / James H. Cane and Jerome G. Rozen, Jr.The first part of this publication, written by a group of participants in Bee Course 2018, results from the discovery of three nests of Caupolicana yarrowi (Cresson, 1875) at the base of the Chiricahua Mountains in southeastern Arizona. The nests are deep with branching laterals that usually connect to large vertical brood cells by an upward turn before curving downward and attaching to the top of the chambers. This loop of the lateral thus seems to serve as a "sink trap," excluding rainwater from reaching open cells during provisioning. Although mature larvae had not yet developed, an egg of C. yarrowi was discovered floating on the provisions allowing an SEM examination of its chorion, the first such study for any egg of the Diphaglossinae. Larval food for this species at this site came from Solanum elaeagnifolium Cav. (Solanaceae). Nests were parasitized by Triepeolus grandis (Friese, 1917) (Epeolini), which previously was known to attack only Ptiloglossa (Diphaglossinae: Caupolicanini). The subterranean nest cells of the desert bee Caupolicana yarrowi (Colletidae), which are enveloped by a casing of hardened soil that easily separates from the surrounding matrix, are discussed in a separate appendix. Chemical analysis revealed the casing to be rich in reducing sugars, indicating that the mother bee had regurgitated floral nectar onto the rough interior walls of the cell cavity before smoothing and waterproofing them. This novel use of nectar in nest construction is compared with that of other bee species that bring water to a nest site to soften soil for excavation
Lower jaws of Spathites.
Full text link12 pages : illustrations (some color), color map ; 26 cm.A lower jaw was recently discovered in a limestone concretion in association with the Late Cretaceous (Turonian) ammonite Spathites puercoensis (Herrick and Johnson, 1900) from the Carlile Member of the Mancos Shale in Sandoval County, New Mexico. It is nearly complete and comprises the aptychus with a hinge along the midline. The better-preserved plate, the left (according to its position in life), is roughly triangular in shape with a broadly rounded lateral margin, a narrowly rounded posterior margin, and a weakly concave anterior margin. It is 26.2 mm wide and 33.0 mm long. Together, the left and right plates form an escutcheonlike shape that projects slightly forward at the apex. The ratio of jaw width to length (26.2 mm x 2 / 33.0 mm) equals 1.59. The aptychus consists of yellow-orange calcite and is covered with comarginal ribs that parallel the lateral and posterior margins and become more prominent toward the posterior end. It is likely that this jaw belongs to the associated ammonite and would have comfortably fit inside the body chamber, based on a comparison of the length of the jaw and the whorl height, suggesting that it functioned as a jaw, rather than as an operculum. It is the first report of an ammonite jaw in the genus Spathites and the first reported occurrence of an ammonite jaw from New Mexico
New species of Inbiomyia from the Atlantic Forest.
Full text link17 pages : illustrations (some color), color maps ; 26 cm.We describe and illustrate Inbiomyia azevedoi, sp. nov., the first species of Inbiomyiidae known from the Atlantic Forest in southeastern Brazil. SEM photos show that the bifurcated labella have on their ventral face rows of scalelike rasping teeth that may be used to graze on green algae, as the gut content of some specimens suggest. A reanalysis of the phylogeny of the genus using Australimyza mcalpineorum as designated outgroup and including I. azevedoi shows that all four groups of species previously proposed for the genus are monophyletic if I. anodonta is removed from the scoliostylus group. Inbiomyia anodonta and I. azevedoi are here transferred to the anemosyris group. In our results with implied weight, I. exul is sister to a clade including all other species of the genus, while the scoliostylus group appears as sister to the clade (mcalpineourum group + anemosyris group)
Supplemental Material for 'A trilobite cluster from the Silurian Rochester Shale of New York : predation patterns and possible defensive behavior. (American Museum novitates, no. 3937)'
No full textSupplemental Material for 'A trilobite cluster from the Silurian Rochester Shale of New York : predation patterns and possible defensive behavior. (American Museum novitates, no. 3937)
Halictid musculature.
No full text28 pages : illustrations (chiefly color) ; 26 cm.Bees of the family Halictidae (Apoidea: Anthophila) have three pairs of thick, bundled muscles that are circular to subcircular in cross section within the first metasomal segment, as revealed by micro-CT scanning of 16 species in 15 genera of five bee families. In nonhalictids and the basal halictid subfamily Rophitinae, these muscles are planar (flat and sheetlike), typically lying between the anterior air sacs and abdominal wall. In Nomiinae and Halictinae, these muscles, especially the dorsal-ventral pair, bulge into air-sac space, partly enveloped by air-sac membrane. A possible function may be to facilitate metasomal compression and contraction, and thus air flow. The bundled shape of these derived halictid muscles is similar to that of flight muscles, but further data is needed to determine if they are fibrillar, which would suggest a completely different function
Marsupials (Didelphimorphia).
Full text link87 pages : illustrations (some color), maps ; 26 cm.This report is the third in our monographic series on mammalian diversity and Matses ethnomammalogy in the Yavarí-Ucayali interfluvial region of northeastern Peru. Based on taxonomic analysis of specimens collected in the region, we document the occurrence of 19 species of marsupials in the genera Caluromys, Glironia, Hyladelphys, Marmosa, Monodelphis, Metachirus, Chironectes, Didelphis, Philander, Gracilinanus, and Marmosops. Our principal taxonomic results include the following: (1) we provide a phylogenetic analysis of previously unpublished mitochondrial DNA (mtDNA) sequence data for Caluromys that supports the reciprocal monophyly of all currently recognized species in the genus but reveals substantial heterogeneity in one extralimital taxon; (2) we explain why Marmosa constantiae is the correct name for the southwestern Amazonian taxon previously known as Mar. demerarae, and we diagnose Mar. constantiae from Mar. rapposa, a superficially similar species from southern Peru, eastern Bolivia, and central Brazil; (3) we explain why Mar. rutteri is the correct name for one of the Amazonian species currently known as Mar. regina, and we restrict the latter name to the transAndean holotype; (4) we recognize Metachirus myosuros as a species distinct from Met. nudicaudatus based on morphological comparisons and a phylogenetic analysis of new mtDNA sequence data; and (5) we name a new species of Marmosops to honor the late Finnish-Peruvian naturalist Pekka Soini. Of the 19 marsupial species known to occur in the Yavarí-Ucayali interfluve, 16 have been recorded in sympatry at Nuevo San Juan, the Matses village where we based most of our fieldwork from 1995 to 1999. We explain why we believe the marsupial species list from Nuevo San Juan to be complete (or nearly so), and we compare it with a species list obtained by similarly intensive fieldwork at Paracou (French Guiana). Although Nuevo San Juan and Paracou are 2500 km apart on opposite sides of Amazonia, the same opossum genera are present at both sites, the lists differing only in the species represented in each fauna. We briefly discuss current explanations for spatial turnover in species of terrestrial vertebrates across Amazonian landscapes and provide evidence that the upper Amazon is a significant dispersal barrier for marsupials. Marsupials are not important to the Matses in any way. In keeping with their cultural inattention to mammals that are inconspicuous, harmless, and too small to be of dietary significance, the Matses lexically distinguish only a few kinds of opossums, and they are not close observers of opossum morphology or behavior