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Reinterpretation of La Meseta tardigradan.
No full text21 p. : ill. ; 26 cm.
"June 25, 2010."
Includes bibliographical references (p. 19-21).An isolated and incomplete tooth, discovered in sediments of Middle Eocene La Meseta Fm on Seymour Island (northern Weddell Sea, West Antarctica), has previously been interpreted to be that of a sloth. The specimen as preserved is composed of dentine, as in sloths and tooth-bearing xenarthrans generally. However, characters associated with the dentinal histology of definite sloths are either not represented on the Seymour tooth, or depart considerably from tardigradan and even general xenarthran models according to new observations presented here. On the basis of histological criteria, the La Meseta tooth cannot be shown positively to be tardigradan; it may not even be xenarthran. Further progress with establishing its relationships will depend on the recovery of more (and better) specimens. For the moment, it is best attributed to Mammalia, incertae sedis
Stenoonops and Australoonops.
No full text111 p. : ill. ; 26 cm.
"Issued July 21, 2010."
Includes bibliographical references (p. 110-111) and index.The goblin spider genus Stenoonops Simon is relimited to include those spineless oonopids with a soft abdomen but a well-sclerotized cephalothorax, elevated and pointed sternal extensions separated by distinct grooves, and a dorsal, distal clump of short setae on the male and female palpal tarsi. Most of the 19 species currently assigned to Stenoonops belong elsewhere; the 14 misplaced species include members of six other genera. As relimited, Stenoonops comprises 23 species and is circum-Caribbean in distribution. The Mediterranean type species of Oonopinus Simon, O. angustatus (Simon), is poorly known, but none of the New World taxa that have been placed in Oonopinus are actually congeneric with O. angustatus. Oonopinus pretiosus Bryant is transferred to Stenoonops; O. centralis Gertsch and O. modestus Chickering are transferred to Theotima (Ochyroceratidae). The genus Scaphioides Bryant is removed from the synonymy of Stenoonops; S. minutus Chamberlin and Ivie from Florida, S. reductus (Bryant) and S. nitens Bryant from the Virgin Islands, S. cletus Chickering and S. hoffi Chickering from Jamaica, S. phonetus Chickering and S. econotus Chickering from Puerto Rico, and S. halatus Chickering from Antigua are transferred from Stenoonops to Scaphioides. Members of two other genera resemble those of Stenoonops but lack distinct grooves between the sternal projections. In the new genus Longoonops, also circum-Caribbean, the posterior median eyes are elongated and color patterns often occur on the abdomen or legs; Stenoonops padiscus Chickering, from Jamaica, is transferred to Longoonops. In Australoonops Hewitt, the seam between the male palpal bulb and cymbium has been lost; females of the type species, A. granulatus Hewitt from South Africa, are described for the first time. New species are described in all three genera, including 17 species of Stenoonops (S. peckorum from Florida, S. alazan and S. cabo from Mexico, S. belmopan from Belize, S. murphyorum from Costa Rica, S. canita from Panama, S. tayrona and S. kochalkai from Colombia and Venezuela, S. bimini from the Bahama Islands, S. mandeville from Jamaica, S. jara from Hispaniola, S. luquillo from Puerto Rico, S.saintjohn, S. tortola, and S. exgord from the Virgin Islands, S. saba from Saba Island, and S. simla from Trinidad), three species of Longoonops (L. bicolor from Nicaragua and Costa Rica, L. chickeringi from Panama, and L. gorda from the Virgin Islands), and two species of Australoonops (A. skaife and A. haddadi from South Africa and Mozambique)
Gilmoreosaurus mongoliensis.
No full text49 p. : ill. ; 26 cm.
"August 23, 2010."
"The first fossil remains of Gilmoreosaurus mongoliensis were collected in 1923 by George Olsen during the Central Asiatic Expeditions of the American Museum of Natural History ... from two quarries ... in the Upper Cretaceous Iren Dabasu Formation, Inner Mongolia, northern China"--P. 2.The osteology of the hadrosauroid dinosaur Gilmoreosaurus mongoliensis is redescribed in detail based on the disarticulated cranial and postcranial elements of at least four individuals. These together constitute the lectotype and hypodigm of this species. The diagnosis is emended to include two autapomorphies (paddle-shaped postacetabular process that is less than 70% of the length of the iliac central plate and manual phalanx III-1 with greatly asymmetrical distal surface) and the unique combination of two iliac characters (presence of ischial tuberosity and supraacetabular process with apex located posterodorsal to ischial peduncle). The distinction of G. mongoliensis from B. johnsoni is confirmed on the basis of characters of the maxilla, dentition, ilium, ischium, and pubis. Maximum parsimony analysis places G. mongoliensis as a closely related outgroup to the Hadrosauridae, the sister taxon to the clade composed of all hadrosauroids closer to Telmatosaurus transsylvanicus than to Bactrosaurus johnsoni
Didelphid marsupial genus Thylamys.
No full text67 p. : ill. (1 col.), maps (some col.) ; 26 cm.
"Issued December 16, 2010."Species of the didelphid marsupial genus Thylamys, commonly known as fat-tailed mouse opossums, are broadly distributed in the open habitats of central and southern South America. In this report we examine species limits in the genus and infer phylogenetic relationships among Thylamys species using both molecular phylogenetic and morphological methods. We assessed species limits using a broad geographic sample of DNA sequences from the mitochondrial gene cytochrome b in conjunction with morphological character analysis, and we inferred phylogenetic relationships among species using the cytochrome-b dataset in addition to sequences from the mitochondrial genes cytochrome c oxidase subunit II and NADH dehydrogenase 2 for a representative subset of individuals. Based on the results of these analyses, we recognize Xerodelphys (new subgenus) for T. karimii and T. velutinus, and we recognize seven valid species in the nominotypical subgenus. The latter includes T. macrurus, T. pusillus, and two monophyletic species groups: the Elegans Group (T. elegans, T. pallidior, T. tatei) and the Venustus Group (T. sponsorius, T. venustus). Analysis of cytochrome-b sequences additionally reveals deep phylogeographic structuring in three species (T. pallidior, T. pusillus, T. venustus), each of which contains two or three robustly supported allopatric haplogroups. The existence of undescribed Peruvian forms of the Elegans Group is also plausibly indicated. We provide morphological diagnoses of all species recognized as valid in this report, summarize information about geographic distributions, comment on previous misidentifications, and briefly consider historical-biogeographic scenarios with a focus on dispersal events across the Andes
AMNH type specimens of birds.
No full text178 p. : 1 ill. ; 26 cm.
"Issued June 3, 2010."
Pts. 1-3 & 5-7 issued as v. 150, article 3 (1973), v. 161, article 1 (1978), no. 257 (2000), no. 278 (2003), no. 292 (2005), and no. 313 (2008) of Bulletin of the American Museum of Natural History; pt. 4 issued as no. 2879 (1987) of American Museum novitates.
Includes bibliographical references (p. 152-169)This eighth part of "Type specimens of birds in the American Museum of Natural History" includes taxa covered in volume 12 of the Check-list of birds of the world (Paynter, 1967) except for the families Zosteropidae and Meliphagidae, which will comprise a separate part. The original description of each form has been consulted unless otherwise noted, coordinates for type localities are given when possible, currently accepted names for the taxa included, and comments on taxonomic history provided. In all, 419 names are treated, five of these being replacement names; 102 of them were introduced by G.M. Mathews. Types of 12 of these names are not in AMNH or were not found. Four paratypes are discussed, the holotypes of which were almost certainly destroyed in World War II. This part of the type list, as well as all previous parts, are searchable and available for download from the AMNH Library web site: http://digitallibrary.amnh.org/dspace/
Troglomorphic scorpion Troglotayosicus humiculum (Scorpiones, Troglotayosicidae).
No full text19 p. : ill. (some col.), map ; 26 cm.
"June 25, 2010."
Includes bibliographical references (p. 18-19).The endemic Colombian troglomorphic scorpion, Troglotayosicus humiculum Botero-Trujillo and Francke, 2009, previously known only from the juvenile holotype, is redescribed based on newly collected adults of both sexes. New data on basitarsal spination, telotarsal setation, and carination of the metasoma and pedipalps, together with the first description of the hemispermatophore and a revised interpretation of the trichobothria, are provided, along with brief discussions of the ecology and distribution of the species
Scaphites of the "nodosus group" from the Upper Cretaceous (Campanian) of the Western Interior of North America. (Bulletin of the American Museum of Natural History, no. 342)
Get PDF242 p. : ill., maps ; 26 cm.
"Issued September 21, 2010."Scaphitid ammonites (scaphites) are common in the Upper Cretaceous Pierre Shale and Bearpaw Shale of the Western Interior of North America. We redescribe Hoploscaphites nodosus (Owen, 1852) and H. brevis (Meek, 1876) from the Baculites compressus–B. cuneatus zones of the upper Campanian. The types of both of these species were collected in the mid-19th century in what was then called Nebraska Territory, and included parts of present-day South Dakota,
North Dakota, and Montana. Based on our present knowledge of the distribution of these species, the type material was probably collected from the B. compressus–B. cuneatus zones in the Pierre Shale at Sage Creek, a tributary of the Cheyenne River, Pennington County, South Dakota. Traditionally, the more robust, more coarsely ornamented scaphites (comprising the "nodosus group") from the Pierre Shale and Bearpaw Shale were assigned to Jeletzkytes Riccardi, 1983, and the more slender, more finely ornamented scaphites were assigned to Hoploscaphites Nowak, 1911. However, our large collections of these scaphites from the Baculites compressus–B. cuneatus zones reveal a complete intergradation between the two morphological extremes, and for many specimens, the choice of genus is arbitrary. In addition, our studies of other biostratigraphic zones in the Pierre Shale and Bearpaw Shale reveal that cooccurring species of these two "genera" share more in common with each other than they do with congeneric species
from other horizons. Furthermore, contrary to earlier assumptions, Jeletkytes is not endemic to the Western Interior Basin of North America and occurs, for example, in the U.S. Atlantic Coastal Plain and Europe. We thus provisionally treat Jeletzkytes as a junior subjective synonym of Hoploscaphites. This expanded definition of Hoploscaphites is consistent with present-day concepts of other scaphitid genera such as Discoscaphites Meek, 1876, and Trachyscaphites Cobban and Scott, 1964..
Hybridization among whiptail lizards.
No full text43 p. : ill. (some col.) ; 26 cm.
"October 11, 2010."The natural origin of diploid parthenogenesis in whiptail lizards has been through interspecific hybridization. Genomes of the parthenogens indicate that they originated in one generation, as the lizards clone the F₁ hybrid state. In addition, hybridization between diploid parthenogens and males of bisexual species has resulted in triploid parthenogenetic clones in nature. Consequently, the genus Aspidoscelis contains numerous gonochoristic (= bisexual) species and numerous unisexual species whose closest relatives are bisexual, and from whom they originated through instantaneous sympatric speciation and an abrupt and dramatic switch in reproductive biology. In order to study this phenomenon more closely, with hopes (unfulfilled) to witness the origin of parthenogenetic cloning in one generation, we maintained whiptail lizards in captivity. For more than 29 years, we caged males of bisexual species with females of bisexual and of unisexual species in attempts to obtain laboratory hybrids. Hybrids were raised to adulthood to see whether they would reproduce, but none did. The hybrid status of suspected laboratory hybrids was confirmed by karyotypic, allozyme, and morphological analyses, and histological studies were made on reproductive tissues of the hybrids, which were apparently sterile. The present paper focuses on the laboratory hybrids of two bisexual species, A. inornata arizonae ([female]) x A. tigris marmorata ([male]). These three individuals from one clutch of eggs were the only hybrids between two bisexual species that we obtained. The hybrids had a karyotype, allozymes (21 loci tested), and external morphology that were similar to those of A. neomexicana, which is a diploid parthenogen that had a hybrid origin in nature that was the reciprocal cross: A. t. marmorata ([female]) x A. inornata ([male]). Histological study showed that the largest and oldest laboratory hybrid raised, which appeared to be a female with inherited X chromosome of A. t. marmorata, was an intersex with an enormous adrenal. The other hybrid that reached adult size, a male, was also apparently sterile. Later, we review and summarize the information on the other laboratory hybrids we obtained over the years. These include two different combinations of hybrids between a male of a bisexual species and females of unisexual species (one diploid, one triploid), producing triploid and tetraploid hybrids, respectively, as a haploid genome from the male was added to the cloned egg. Considering only those specimens whose hybrid status was confirmed with genetic analyses, a total of only five hybrids from three crosses were obtained over 29 years. The effort involved having a total of 74 males of four species caged with 156 females of nine species, where individuals were caged together for at least six months (or less, if mating behavior was observed). Despite our extensive efforts to provide for their comfort and best health and captive environment, the lizards at times experienced health problems such as metabolic bone disease and a Salmonella infection. These definitely had a negative effect on reproduction, the full extent of which is unknown. Nevertheless, we estimate that successful hybridization among whiptail lizards (i.e., which results in healthy offspring capable of reproduction) is much more rare than we previously thought, although, paradoxically, it is far more common among Aspidoscelis than among nearly all other genera of lizards in the world, with the possible exception of lacertids
Ornithological exploration of Amazonian Peru.
No full text68 p. : ill., maps ; 26 cm.
"Issued December 8, 2010."In 1922 Frank M. Chapman hired a family of Ecuadorians to collect birds and mammals for the American Museum of Natural History (AMNH). In the following two years, Carlos Olalla and his four sons (especially Alfonso and Ramón) shipped some 3500 carefully prepared and neatly labeled specimens of Ecuadorian birds to New York. In 1925, under a new contract with the AMNH, the Olallas moved their operations to northeastern Peru, and during the next two and a half years, mostly as a result of efforts by Alfonso and Ramón, they sent over 7000 specimens of birds to New York from Amazonian Peru, as well as additional thousands of specimens of mammals. The two brothers shifted their operations to Brazil in 1928. Alfonso went on to ship even larger collections of birds from Brazil to museums in the United States, Sweden, and Brazil. Altogether these collections have provided the documentation for much of what we now know about the distributions of Amazonian birds and mammals. In 1962 accusations surfaced that the Olallas had falsified much of the information about their specimens. Although based on hearsay, these accusations raised lingering doubts about the Olallas' collections. Alfonso sent reports of the brothers' activities to the AMNH with their shipments of specimens. These reports together with their correspondence with Chapman and other curators are still preserved in the archives of the departments of ornithology and mammalogy. Examination of these archives and of most of the Olallas' specimens of birds and primates from Peru provides a clear view of their activities for the first time. All of the Olallas' collecting sites in Amazonian Peru can now be confidently located, and a large majority of their specimens from these localities accord with current understanding of avian distributions in Amazonian Peru. The accusations of general carelessness or systematic duplicity can thus be rejected. Nevertheless, there remains a small number of problematic specimens. Especially suspect are those acquired from the Olallas in Iquitos by Harvey Bassler with labels from the mouth of the Río Urubamba. These specimens eventually came to the AMNH as a part of Bassler's collection, rather than directly from the Olallas. Alfonso and Ramón Olalla's choice of collecting sites suggests that they became aware of the importance of major rivers in limiting avian distributions in Amazonia, and their correspondence with Chapman suggests that their collections brought this insight to the attention of ornithologists in New York. In addition, their collections suggest patterns of avian distribution that still need further investigation, especially the extension of some species of the Andean foothills into the lowlands of upper Amazonia and the less consistent limitations of avian distributions by the upper Río Ucayali in comparison to the Río Amazonas. No doubt some of the Olallas' specimens indicate yet undiscovered features of avian distribution in upper Amazonia, where, despite Alfonso and Ramón's pioneering efforts, there is surely more to learn