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Fourteen new, endemic species of shrew (genus Crocidura) from Sulawesi reveal a spectacular island radiation (Bulletin of the American Museum of Natural History, no. 454)
No full text108 pages : illustrations (some color), maps ; 26 cm.After nearly a decade of field inventories in which we preserved voucher specimens of the small terrestrial mammals of Sulawesi, we combined qualitative and quantitative analyses of morphological traits with molecular phylogenetics to better understand the diversity of shrews (Soricidae: Crocidura) on the island. We examined the morphology of 1368 specimens and obtained extensive molecular data from many of them, including mitochondrial DNA sequences from 851 specimens, up to five nuclear exons from 657 specimens, and thousands of ultraconserved elements from 90 specimens. By iteratively testing species limits using distinct character datasets and appropriate taxon sampling, we found clear, mostly consistent evidence for the existence of 21 species of shrews on Sulawesi, only seven of which were previously recognized. We divide these 21 species into five morphogroups, provide emended diagnoses of the seven previously named species, and describe 14 new species. The Long-Tailed Group contains Crocidura caudipilosa, C. elongata, C. microelongata, new species, and C. quasielongata, new species; the Rhoditis Group contains C. rhoditis, C. pseudorhoditis, new species, C. australis, new species, and C. pallida, new species; the Small-Bodied Group contains C. lea, C. levicula, C. baletei, new species, C. mediocris, new species, C. parva, new species, and C. tenebrosa, new species; the Thick-Tailed Group contains C. brevicauda, new species and C. caudicrassa, new species; and the Ordinary Group contains C. musseri, C. nigripes, C. normalis, new species, C. ordinaria, new species, and C. solita, new species. Documenting these endemic species reveals a local radiation (20 of the 21 species are members of an endemic clade) in which elevational gradients played a prominent role in either promoting speciation, or at a minimum, fostering the cooccurrence of phenotypically similar species. As now understood, the species-level diversity of Crocidura on Sulawesi is nearly three times the known diversity of any other insular shrew fauna. This study highlights the fact that if we wish to understand the true extent of biodiversity on Earth, large-scale, vouchered organismal inventories followed up with thorough examinations of genetic, morphological, and geographic traits are sorely needed in montane tropical regions, even for purportedly well-studied groups such as mammals
Evolution in Rhinella (Anura: Bufonidae)
Full text link155 pages : illustrations (some color) ; 26 cm.True toads of the genus Rhinella are among the most common and diverse group of Neotropical anurans. These toads are widely distributed throughout South America, inhabiting a great diversity of environments and ecoregions. Currently, however, the genus is defined solely on the basis of molecular characters, and it lacks a proper diagnosis. Although some phenetic species groups have traditionally been recognized within Rhinella, the monophyly of some of them have been rejected in previous phylogenetic analyses, and many species remain unassigned to these poorly defined groups. Additionally, the identity and taxonomy of several species are problematic and hinder the specific recognition and description of undescribed taxa. In this work, we first perform phylogenetic analyses of separate mitochondrial and nuclear datasets to test the possible occurrence of hybridization and/or genetic introgression in the genus. The comparative analysis of both datasets revealed unidirectional mitochondrial introgressions of an unknown parental species into R. horribilis ("ghost introgression") and of R. dorbignyi into R. bernardoi; therefore, the mitochondrial and nuclear datasets of these species were considered separately in subsequent analyses. We performed total-evidence phylogenetic analyses that included revised molecular (four mitochondrial and five nuclear genes) and phenotypic (90 characters) datasets for 83 nominal species of Rhinella, plus several undescribed and problematic species and multiple outgroups. Results demonstrate that Rhinella was nonmonophyletic due to the position of R. ceratophrys, which was recovered as the sister taxon of Rhaebo nasicus with strong support. Among our outgroups, the strongly supported Anaxyrus + Incilius is the sister clade of all other species of Rhinella. Once R. ceratophrys is excluded, the genus Rhinella is monophyletic, well supported, and composed of two major clades. One of these is moderately supported and includes species of the former R. spinulosa Group (including R. gallardoi); the monophyletic R. granulosa, R. crucifer, and R. marina Groups; and a clade composed of the mitochondrial sequences of R. horribilis. The other major clade is strongly supported and composed of all the species from the non-monophyletic R. veraguensis and R. margaritifera Groups, the former R. acrolopha Group, and R. sternosignata. Consistent with these results, we define eight species groups of Rhinella that are mostly diagnosed by phenotypic synapomorphies in addition to a combination of morphological character states. Rhinella sternosignata is the only species that remains unassigned to any group. We also synonymize nine species, treat three former subspecies as full species, and suggest that 15 lineages represent putative undescribed species. Lastly, we discuss the apparently frequent occurrence of hybridization, deep mitochondrial divergence, and "ghost introgression"; the incomplete phenotypic evidence (including putative character systems that could be used for future phylogenetic analyses); and the validity of the known fossil record of Rhinella as a source of calibration points for divergence dating analyses
A new Troglomorphic, leaf-litter scorpion from Ecuador (Troglotayosicidae: Troglotayosicus) (American Museum novitates, no. 3981)
Full text link24 pages : illustrations (some color), map ; 26 cm.For several decades, Troglotayosicus Lourenço, 1981, remained an enigmatic, monotypic scorpion genus believed to be troglobitic. The discovery and description in recent years of several endogean species of the genus, inhabiting the leaf litter of tropical rainforests in Colombia and Ecuador, advanced knowledge about these scorpions. The known distribution of Troglotayosicus was considerably expanded along the Andes, and it was demonstrated that, despite the absence of median ocelli, the genus is composed primarily of species that inhabit leaf litter. In the present study, Troglotayosicus ballvei, sp. nov., is described from Sacha Huagra Lodge, adjacent to Archidona Municipality, in Napo Province, Ecuador, raising the number of Troglotayosicus species to six, three each in Colombia and Ecuador. An updated map of the known distribution of the genus is presented
A new dromaeosaurid (Dinosauria: Coelurosauria) from Khulsan, Central Mongolia (American Museum novitates, no. 3982)
Full text link47 pages : color illustrations ; 26 cm.
Includes erratum: On page 34, the phrase “absence of a fourth trochanter of the femur (char. 184.1)” should read “presence of a fourth trochanter of the femur (char. 184.0)”.Dromaeosaurid theropods represent a rare but important clade of nonavialan dinosaurs. Their close evolutionary relationship to modern birds has placed them at the center of paleontological research for the last several decades. Herein we describe a new species of dromaeosaurid—Kuru kulla, gen. et sp. nov.—based on a partial skeleton from the Late Cretaceous Khulsan locality (Barun Goyot Formation) of Mongolia. This species is diagnosed by several autapomorphies within Dromaeosauridae, including a sharp groove anterior and ventral to the narial fossa on the premaxilla, a posterolaterally directed hornlet on the posterodorsal process of the lacrimal, a deep surangular bearing two surangular foramina, and anteriorly displaced pleurocoels on the dorsal centra. The taxon is further characterized by a unique combination of characters, including a mediolaterally narrow metatarsal II, serrations on both carinae of the dentary teeth, hyposphenes that are widely separated but joined by a web of bone, and a lacrimal with a poorly developed boss on its lateral surface. Phylogenetic analysis finds Kuru kulla to be the sister taxon of Adasaurus mongoliensis, from the slightly later Nemegt Formation, with which it is united by three synapomorphies: a posterior surangular foramen that is ~30% the depth of the surangular, absence of a fourth trochanter of the femur, and thoracic centra that are markedly longer than their midpoint widths. The recognition of this taxon has important implications for common assumptions of Mesozoic terrestrial ecosystem structure and adds new data to a recently recognized pattern in dromaeosaurid faunal composition among Late Cretaceous localities in Mongolia and Inner Mongolia (Nei Mongol Autonomous Region, China)
Supplemental Material for '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)'
No full textSupplemental Material for '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)
Biofluorescence in Arctic snailfishes
Full text link12 pages : illustrations (chiefly color) ; 26 cm.Biofluorescence has recently been reported to be phylogenetically widespread and phenotypically variable across bony fishes, and is most common in tropical coral reef lineages. Here we provide the first documentation of prominent biofluorescence in Arctic fishes including two juvenile specimens of Liparis gibbus (variegated snailfish) collected from the coastal waters of Eastern Greenland, as well as an adult L. tunicatus (kelp snailfish) collected in the Bering Strait off of Little Diomede Island, AK. Observations of L. gibbus were made during nighttime dives within kelp forests in iceberg habitats in Southeastern Greenland in August 2019. The juvenile L. gibbus specimens exhibit both green (523-530 nm) and red (674-678 nm) biofluorescence on discrete anatomical areas, which provides a rare example of multiple fluorescent colors emitted from a single individual. Notably, the adult L. tunicatus emitted only red fluorescence in a bilaterally symmetrical pattern of discrete red dots and blotches. Potential weak green biofluorescence was also noted in a flatfish (Hippoglossoides platessoides) collected in Greenland, but in no other Arctic species. As the distribution and function of biofluorescence in marine fishes is further examined, this report adds context to its widespread geographical and environmental distributions, and shows that, although rare, biofluorescence does occur in Arctic fish lineages
Leiinae (Diptera: Mycetophilidae)
Full text link108 pages : color illustrations ; 26 cm.The relationships among the genera of fungus gnats in the mycetophilid subfamily Leiinae are unclear, and the monophyly of this group is questionable. This monograph provides an extensive phylogenetic study of theLeiinae based on morphological data from a large taxonomic sample, including all genera that have ever been assigned to the subfamily and a wide outgroup sampling to properly test subfamilial monophyly. A data matrix with 128 morphological features of 117 terminal taxa was carried out under parsimony using different implicit weight schemes. All recovered topologies support a monophyletic Leiinae that is more restricted than the usual delimitation of the subfamily. We found no consistent evidence that a clade with Docosia Winnertz, Novakia Strobl, Ectrepesthoneura Enderlein, and Tetragoneura Winnertz group together with the remaining genera of Leiinae. A name with subfamily rank--Tetragoneurinae, already present in the literature--is used here to refer to this group. The allactoneurine genera Sticholeia Søli and Allactoneurade Meijere form a clade with the leiine genus Leiella and the genera of Manotinae, which is deeply nested within the Leiinae. The male terminalia patterns found within the subfamily are analyzed and illustrated. A classification for the Leiinae is proposed grouping 33 genera in seven clades ranked as tribes: Selkirkiini Enderlein, Megophthalmidiini, trib. nov., Rondaniellini, trib. nov., Cycloneurini Shaw and Shaw, Manotini Edwards, Anomalomyiini, trib. nov., and Leiini Edwards. A key for the world genera of Leiinae is also provided. The Cretaceous mycetophilid fossil record is revisited and the biogeographic evolution of the Leiinae is discussed
Total-evidence phylogeny of the New World Polistes Lepeletier, 1836, paper wasps (Vespidae, Polistinae, Polistini) (American Museum novitates, no. 3973)
No full text42 pages : illustrations (chiefly color) ; 26 cm.The genus Polistes is one of the most species-rich and widely distributed groups of social wasps and a model taxon for studies of social behavior. Almost half the Polistes world fauna occurs in the New World, but their classification has been unstable due in part to the scarcity of phylogenetic studies. We investigated the phylogeny of the New World Polistes by combining a previously existing molecular dataset with a new morphological and behavioral matrix for 90 of the 93 New World species. All analyses support a single origin for the New World Polistes. All five traditionally defined New World subgenera (Aphanilopterus, Epicnemius, Fuscopolistes, Onerarius, and Palisotius) were monophyletic, but the relationships among them varied across datasets. Our results, with an expanded phenotypic dataset, improved taxonomic sampling, and enhanced clade support relative to previous studies, strongly support a classification based on five subgenera, which are all diagnosable groups supported by clear morphological synapomorphies. Hence, we propose the revalidation of previously proposed subgenera; we provide a taxonomic account of each subgenus and an identification key to all species of New World Polistes
Intratribal variation among mature larvae of stingless bees (Apidae: Meliponini) with descriptions of the eggs of 11 species (American Museum novitates, no. 3971)
Full text link47 pages : illustrations ; 26 cm.The abundant members of the Meliponini (stingless bees) are restricted to the tropics and subtropics worldwide. Because past studies of the anatomy of their mature larvae are limited, revealing little anatomical variation in the tribe, the current investigation attempts to examine this topic more thoroughly. Herein we describe the mature larvae of 30 species representing 16 genera of a total world fauna of perhaps 32 genera. Although the larvae of most taxa show little anatomical diversity, two species, Trigona (Duckeola) ghilianii Spinola and Trigona (Frieseomelitta) varia (Lepeletier), have mature larvae that differ remarkably in anatomical structure from those of other known stingless bees, and, further, their individual anatomies suggest a close evolutionary relationship. Larval evidence is presented indicating that Trichotrigona extranea (Camargo and Moure) is also related to these two taxa. Because eggs are often included in collections of bee larvae, this study adds descriptions of the eggs of 11 species of the Meliponini not previously characterized as well as a list of those that had been treated earlier
Total evidence phylogenetic analysis supports new morphological synapomorphies for Bovidae (Mammalia, Artiodactyla) (American Museum novitates, no. 3970)
No full text38 pages : illustrations ; 26 cm.Advances in gene sequencing technology have made it easier to generate large molecular datasets with novel DNA sequences for phylogenetic analysis. Because morphological data are difficult to collect and not required for molecular phylogenetic analyses, they are often excluded in studies of the systematic relationships of extant taxa. This fact is especially apparent in the Bovidae, the highly diverse, widespread clade of hoofed mammals most often characterized by the presence of permanent bony horn cores covered with keratin sheaths. Analyses of molecular data have reconstructed well-supported phylogenetic relationships within the clade. However, morphological data are also required to integrate fossil taxa into these studies, and may support different topologies when they are included in total evidence phylogenies. In this study, I performed a maximum likelihood phylogenetic analysis of a total evidence dataset including mitochondrial genomes, nine nuclear genes, and 196 morphological characters. The dataset comprises 156 species, 13 of which are fossil taxa, one of the most complete analyses of the family to date, and the first time many of the fossil species have been included in a total evidence analysis. Character optimizations on this topology produced seven synapomorphic morphological characters for Bovidae and multiple characters for each tribe. These analyses support the use of total evidence phylogenetics as a means of uncovering morphological characters that may serve as new synapomorphies and elucidate the systematic relationships of fossil species