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Molecular systematics of mouse opossums (Didelphidae, Marmosa) : assessing species limits using mitochondrial DNA sequences, with comments on phylogenetic relationships and biogeography. (American Museum novitates, no. 3692)
No full text22 p. : ill., maps (some col.) ; 26 cm.
"June 25, 2010."
Includes bibliographical references (p. 18-21).The genus Marmosa contains 15 currently recognized species, of which nine are referred to the subgenus Marmosa, and six to the subgenus Micoureus. Recent revisionary research based on morphological data, however, suggests that the subgenus Marmosa is more diverse than the currently accepted taxonomy indicates. Herein we report phylogenetic analyses of sequence data from the mitochondrial cytochrome-b gene representing 12 of the 14 morphologically defined taxa recently treated as valid species of Marmosa (Marmosa) in the aforementioned revisionary work. These data provide a basis for testing the monophyly of morphologically defined taxa in the subgenus Marmosa, and they afford the first opportunity to assess phylogenetic relationships among the majority of species currently referred to the genus. Ten of 11 species of Marmosa (Marmosa) represented by multiple sequences in our analyses were recovered as monophyletic. In contrast, our samples of M. mexicana were recovered as two deeply divergent haplogroups that were not consistently associated as sister taxa. Among other results, our analyses support the recognition of M. isthmica and M. simonsi as species distinct from M. robinsoni, and the recognition of M. macrotarsus and M. waterhousei as species distinct from M. murina. The validity of three other species long recognized as distinct (M. rubra, M. tyleriana, and M. xerophila) is also clearly supported by our results. Although cytochrome-b sequence data are not consistently informative about interspecific relationships in this study, we found strong support for several clades, including (1) the subgenus Micoureus; (2) a group comprised of Marmosa macrotarsus, M. murina, M. tyleriana, and M. waterhousei; (3) a group comprised of M. robinsoni and M. xerophila; and (4) a group comprising all of the species in the subgenus Marmosa that occur north and west of the Andes (M. isthmica, M. mexicana, M. robinsoni, M. simonsi, M. xerophila, and M. zeledoni). Our discovery of the latter clade suggests that the Andes may have played a major role in the early diversification of this speciose radiation of small Neotropical marsupials
New material of Coryphomys buehleri Schaub, 1937, and description of a second species of the genus.
No full text80 p. : ill. (some col.), maps ; 26 cm.
Issued July 21, 2010.Large collections of fragmentary animal bones excavated from archaeological contexts in East Timor between 1968 and 2002 provide new material referable to the recently extinct, gigantic murine genus Coryphomys. We document the upper and lower dentition and palatal anatomy of C. buehleri Schaub, 1937, and identify and name a second species of Coryphomys, based on differences in molar size and morphology and skeletal robusticity. Alternative interpretations of the observed morphological and metric variability (sexual dimorphism, resource-based polymorphism, sample heterochroneity) are each carefully assessed and rejected, and we conclude that the genus comprised two species of approximately similar body size. Preserved cranial elements of both species of Coryphomys feature a high degree of anatomical specialization, including an unusual elaboration of the maxillary sinus complex. Though the specialized anatomy of Coryphomys invites consideration of its phylogenetic relationships, this exercise is hindered by a demonstrable high level of homoplasy (i.e., multiple, independent evolutionary losses and gains) in many of the key craniodental features traditionally surveyed within Murinae, while other features are insufficiently well surveyed for broad-scale analysis. Nevertheless, our comparisons highlight two potentially related lineages among the geographically proximate Murinae - the Philippine Phloeomyini and the Australo-Papuan Hydromyini. The remains of Coryphomys are relatively scarce in all the archaeological samples, but distributional evidence suggests that both species of Coryphomys were found primarily in upland habitats. Late Pleistocene samples document their former presence at lower elevations, possibly reflecting cooler climatic conditions at that time
Myrtaceae-feeding Phylinae (Hemiptera, Miridae) from Australia : description and analysis of phylogenetic and host relationships for a monophyletic assemblage of three new genera. (Bulletin of the American Museum of Natural History, no. 344)
No full text95 p. : ill. (some col.), maps ; 26 cm.
"Issued December 8, 2010."Three new genera and 25 new species of Myrtaceae-feeding Phylinae are described from Australia. A cladistic analysis of a broader cross section of Australian Phylinae indicates that these taxa all belong to a monophyletic group, on the basis of pretarsal and male genitalic structures. Line drawings are used to present information of male and female genitalic structures; scanning electron micrographs illustrate pretarsal, genitalic, and other morphology. Color digital habitus images are presented for the males and females of all species. Digital images from the field and of pressed specimens are presented for a broad cross section of host plants. The newly described taxa represent a portion of the species of Australian Phylinae known to feed on the Myrtaceae; the remaining Myrtaceae-feeding species belong to other lineages and are therefore excluded from this monograph. Twenty-three of the species are recorded only from southwestern Western Australia; two species are recorded from southeastern South Australia. All species breed on members of the subfamily Myrtoideae, tribes Chamelaucieae and Melaleuceae
Spermatozoa of Pimoidae.
No full text17 p. : ill. (some col.) ; 26 cm.
"March 4, 2010."
Includes bibliographical references (p. 14-17).The spermatozoa of spiders (Araneae) show a high structural diversity, resulting in several potential phylogenetic characters. In the present paper, we describe the spermatozoa of the spider family Pimoidae for the first time. We investigate four species of the genus Pimoa (P. altioculata, P. curvata, P. laurae, and P. edenticulata) by means of light and transmission electron microscopy. The male reproductive system consists of paired testes and long convoluted paired deferent ducts. The spermatozoa are generally characterized by: (1) a cylindrical acrosomal vacuole, (2) an acrosomal filament restricted to the precentriolar part of the nucleus, (3) a nuclear canal running in the periphery but projecting towards the posterior portion of the nucleus, (4) a short postcentriolar elongation of the nucleus, (5) a 9+0 axonemal pattern, and (6) cleistospermia as transfer form. The organization of the axoneme is of particular phylogenetic interest, since a 9+0 axonemal pattern was described within spiders only for the megadiverse family Linyphiidae, the sister group of Pimoidae. We have reconstructed the evolution of the axoneme using comparative spermatozoal data for 54 orbicularian species representing 11 families. We propose that the 9+0 axonemal pattern is a new synapomorphy for Pimoidae + Linyphiidae. The phylogenetic and evolutionary implications of other potential sperm characters (e.g., length of the postcentriolar elongation of the nucleus) are discussed
Spider genus Atimiosa Simon, 1895.
Get PDF19 p. : ill. ; 26 cm.
"March 4, 2010."
Includes bibliographical references (p. 17).The genus Atimiosa Simon, 1895, is a junior synonym of Dolichognatha O. P.-Cambridge, 1869. This synonymy is strongly supported by cladistic analyses of morphological characters and examination of types of all known Atimiosa species. Two new combinations resulted from this nomenclatural change, Dolichognatha comorensis (Schmidt and Krause, 1993), new combination, and Dolichognatha quinquemucronata (Simon, 1895), new combination. New illustrations and photographs of these two species and of the poorly known Dolichognatha longiceps (Thorell, 1895) are provided. We also describe for the first time the web architecture of D. longiceps
Revision of Marmosa.
No full text83 p. : ill. (some col.), maps ; 26 cm.
"Issued June 3, 2010."
Includes bibliographical references (p. 66-71).We revise the nominal species of mouse opossums currently synonymized with Marmosa mexicana Merriam, 1897, and M. robinsoni Bangs, 1898, which include all of the trans-Andean taxa currently assigned to the nominotypical subgenus of Marmosa. In addition, we redescribe two other species that appear to be closely related to M. mexicana and M. robinsoni based on morphological or molecular citeria: M. rubra Tate, 1931, and M. xerophila Handley and Gordon, 1979. Based on first-hand examination of holotypes and other material (about 1500 specimens in total), we additionally recognize M. isthmica Goldman, 1912, and M. simonsi Thomas, 1899 (both currently synonymized with M. robinsoni), and M. zeledoni Goldman, 1917 (currently synonymized with M. mexicana), as valid species. For each of the seven species recognized as valid herein (M. mexicana, M. zeledoni, M. isthmica, M. robinsoni, M. xerophila, M. simonsi, M. rubra), we describe and illustrate diagnostic external and craniodental characters, tabulate measurement data from adult specimens, list all known examples of sympatry, and map geographic ranges based on specimens examined. The species newly recognized as valid herein, all of which occur in Central America and/or northwestern South America, substantially increase the known diversity of trans-Andean mouse opossums, but it is not currently known whether or not these represent a distinct radiation within the genus Marmosa
Niarchos and Scaphios.
No full text120 p. : ill. ; 26 cm.
"Issued December 8, 2010."A new genus, Niarchos, is established for a group of 22 new species from the Andean regions of Colombia, Ecuador, and Peru. Although the males of most of these species are obviously gamasomorphines, with a well-developed dorsal abdominal scutum, that scutum is reduced, in the males of two species, to just a narrow, sclerotized, longitudinal strip that covers only the cardiac area and is fused anteriorly to the epigastric scutum. Females of all species, in contrast, show no trace whatever of a dorsal abdominal scutum, have only short and lightly sclerotized epigastric and postepigastric scuta, and could therefore easily be misidentified as oonopines. Four species groups are recognized within the genus, each characterized by a distinctive form of male palp; the four groups are united by the presence of a triangular, posteriorly directed anterior projection on the male endites as well as by the sexual dimorphism in scutum morphology, reduced posterior eyes, and an unusual leg spination pattern (with spines absent on the anterior legs and present only as slightly enlarged but darkened macrosetae on tibiae, and sometimes metatarsi, III and/or IV). The cotopaxi group includes eight species, six from western Ecuador (N. cotopaxi, N. barragani, N. keili, N. baehrae, N. tapiai, and N. elicioi) and two from southwestern Colombia (N. wygodzinskyi and N. florezi); males of this group are united by a unique retroventral projection on the male palpal bulb. The scutatus group includes seven species from eastern Ecuador (N. scutatus, N. ramirezi, N. bonaldoi, N. vegai, N. santosi, N. michaliki, and N. ligiae); males of this group are united by an embolar base bent at a right angle at about half its length. The loja group includes two species from southern Ecuador and northern Peru (N. loja and N. foreroi) in which the embolus is elongated. The palenque group includes two species from western Ecuador (N. palenque and N. facundoi) in which the distal portion of the embolus is short and translucent. Three Ecuadorean species known only from females (N. grismadoi, N. matiasi, and N. rheimsae) are left unplaced, but apparently represent at least one additional, relatively widespread species group. A second new genus, Scaphios, is described for a group of seven new species from Ecuador (S. yanayacu, S. napo, S. cayambe, S. wagra, S. jatun, S. orellana, and S. puyo), plus one species from southwestern Colombia (S. planada), that resemble those of Niarchos in dorsal scutum morphology and leg spination, but have fully developed posterior eyes, a laterally directed anterior projection on the male endites, and a subdistally originating, sinuous embolus. Males of S. orellana also have reduced dorsal and postepigastric abdominal scuta, but (unlike the Niarchos males with reduced scuta) the dorsal scutum is separate from the epigastric scutum. A shared pattern of sexual dimorphism in ventral pedicel sclerite morphology suggests that Niarchos and Scaphios are sister groups
Melchisedec, a new genus of Oonopidae.
No full text27, [1] p. : ill. (some col.), map ; 26 cm.
"December 10, 2010."A new genus, Melchisedec, is established for two new Afrotropical species, M. thevenot (type species) and M. birni. These spiders are unique among oonopids in having a crest on the ventral pedicel sclerite, and in having very short, scepterlike setae on the distal metatarsi I and II. The male of M. thevenot has a long, inward-curved embolus-conductor complex and a sternal pouch. The embolus-conductor complex resembles that of the Australian genus Grymeus Harvey, but differs in important details. The genital system of the female is highly complex, and includes two uterine sclerites, two winglike lateral apodemes and a receptaculum with a globular appendix. The receptaculum is much larger than in most other Oonopidae and has an unusual, strongly folded surface
New genus of Caponiidae.
No full text44 p. : ill. (some col.), map ; 26 cm.
"December 29, 2010."A new genus, Cubanops, is established for a distinctive group of caponiid spiders from the West Indies. Nops ludovicorum Alayón, from Cuba, and Caponina darlingtoni Bryant, from Hispaniola, are transferred to Cubanops. Nine new species are described from the Bahama Islands (C. bimini, C. andersoni), Cuba (C. armasi, C. alayoni, C. juragua, C. granpiedra, C. terueli, C. tortuguilla), and Hispaniola (C. vega). All these species are nopines (i.e., have subsegmented tarsi) and have the ventral translucent keel on the anterior metatarsi, and the translucent extension of the membrane between the anterior metatarsi and tarsi, that are also found in the genera Nops MacLeay, Orthonops Chamberlin, and Tarsonops Chamberlin. However, Cubanops species lack the dorsally extended inferior claw found in Nops, and differ from those of Orthonops and Tarsonops in having a distinctly patterned carapace, a widened labium, and bisegmented metatarsi IV. Two species groups are recognized within the genus, which probably occurs also in Puerto Rico and the Virgin Islands, as juveniles with these somatic characters have been taken on St. John
