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Revision of the giant vinegaroons.
Full text link62 pages : illustrations (some color), map ; 26 cm.The North American vinegaroon, Mastigoproctus giganteus (Lucas, 1835), is demonstrated to comprise a complex of range-restricted species rather than a single widespread polymorphic species. Seven species are recognized based on morphological characters of the adult males, including the arrangement of spines on the prodorsal margin of the pedipalp trochanter, the position of the epistoma on the carapace, the presence of a stridulatory organ on opposing surfaces of the chelicerae and the pedipalp coxa, the presence of a patch of setae on sternite V, and the shape and macrosculpture of the retrolateral surface of the pedipalp femur. The two currently recognized subspecies are elevated to species: Mastigoproctus mexicanus (Butler, 1872), stat. nov., and Mastigoproctus scabrosus (Pocock, 1902), stat. nov. Mastigoproctus floridanus (Lönnberg, 1897) is revalidated from synonymy with M. giganteus. Redescriptions of M. giganteus and the other three species, based on both sexes, are provided, and three new species described: Mastigoproctus cinteotl, sp. nov., from Tamaulipas, Mexico; Mastigoproctus tohono, sp. nov., from Arizona and Sonora, Mexico; Mastigoproctus vandevenderi, sp. nov., from Sonora, Mexico. The present contribution raises the diversity of the Order Thelyphonida Latreille, 1804, in North America from one species to seven. Three species occur in the United States (one each in Arizona, Texas, and Florida), six species occur in Mexico, and two species occur in both countries
Leeches from Chiapas, Mexico, with a new species of Erpobdella (Hirudinida, Erpobdellidae). (American Museum novitates, no. 3895)
No full text15 pages : illustrations, map ; 26 cm.Freshwater leeches were collected from Chiapas, Mexico. Among these collections and prior records, a total of nine species were found, comprising six genera and four families. One species, Diestecostoma octannulata, represents a new record for Mexico and two species, Helobdella elongata and H. octatestisaca, represent new records for Chiapas. Additionally, a new species of Erpobdella was discovered from a single stream in the park El Arcotete near San Cristobal de las Casas. Here it is described as Erpobdella adani and it is morphologically distinguished from Mexican Erpobdella species by the combination of having the whole body strongly dorsoventrally flattened, three annuli between gonopores, an enlarged male gonopore, and no preatrial loops for the male reproductive system. Based on sequence data (mitochondrial cytochrome c oxidase subunit I and 12S; nuclear 18S), this new species appears most closely related to a clade formed by E. coastalis and E. ochoterenai. Both mitochondrial cytochrome c oxidase subunit I molecular barcodes and morphological descriptions of the collected species are presented
Supplemental Material for 'In situ observations of the meso-bathypelagic scyphozoan, Deepstaria enigmatica (Semaeostomeae, Ulmaridae). (American Museum novitates, no. 3900)'
No full textSupplemental Material for 'In situ observations of the meso-bathypelagic scyphozoan, Deepstaria enigmatica (Semaeostomeae, Ulmaridae). (American Museum novitates, no. 3900)
New Myrtaceae-feeding Phylinae from Australia.
Full text link157 pages : illustrations (some color), color maps ; 26 cm.Six new genera of Australian Phylinae are described on the basis of existing collections. The tribe Exaeretini--represented by the two new genera Eucalyptophylus (two new species) and Melaleucaphylus (18 new species)--is recognized for the first time as occurring in Australia. Nine new taxa of Semiini, subtribe Exocarpocorina, are proposed: Four new genera, Calytriphylus, Melaleucacoris, Teddus (each monotypic), and Leptospermia (two new species), and four new species placed in Ancoraphylus Weirauch, 2007 (one species), Xiphoidellus Weirauch and Schuh, 2011 (one species), and Xiphoides Eyles and Schuh, 2003 (two species). Based on specimen data almost all the new taxa are associated with Myrtaceae plant hosts in the tribes Chamelaucieae, Eucalypteae, Leptospermeae, and Melaleuceae. A new species of Restiophylus Leon and Weirauch, 2016, taken in coastal New South Wales and perhaps associated with Leptocarpus tenax (Restionaceae), represents the first record for this genus beyond the southwest coast of Western Australia. Documentation is provided in the form of diagnoses and descriptions of all genera and species, color habitus images of males (and females when available) of all species, distributional maps, color images of male genitalic structures of all species, female genitalic structures in most species, and scanning electron micrographs of representative morphology of some taxa. Host-plant information is provided for most species, along with representative images of hosts and habitats. New distribution records for Xiphoidellus dumosus Weirauch and Schuh, 2011, and scanning micrographs of the pretarsus for Scholtzicoris linnavuorii Schuh, 2016 are provided
Convergent evolution in Shartegosuchidae palate.
Full text link23 pages : illustrations (some color), color map ; 26 cm.Shartegosuchids are a poorly known, early-branching group of Asian and North American crocodylomorphs. Shartegosuchids have been hypothesized to have eusuchian-type secondary palates, but a paucity of described material makes assessing this difficult. Our fieldwork in western Mongolia recovered cranial material of a new Shartegosuchus specimen from the Ulan Malgait Formation, which we CT-scanned and digitally reconstructed to investigate its palatal morphology. We then incorporated this new anatomical information into a revised phylogenetic dataset to assess its affinities. Our study confirms that Shartegosuchus has a posteriorly placed choana that is fully enclosed by the pterygoids, but differs from Eusuchia in possessing a secondary palatal fenestra and reduced palatine bones. Shartegosuchus, together with Adzhosuchus, Fruitachampsa, and Nominosuchus, forms the monophyletic group Shartegosuchidae. Shartegosuchidae is nested within a larger clade Shartegosuchoidea, and this clade is an earlier-diverging lineage than Eusuchia, showing that a eusuchian-type secondary palate evolved multiple times in crocodylomorphs, including very early in the group's evolutionary history. The co-occurrence of Nominosuchus in the Ulan Malgait Formation and the Shishigou Formation allows us to assign an early Oxfordian age to Shartegosuchus. The independent evolution of a eusuchian-type secondary palate in an oreinorostral group suggests that the link between platyrostry and a closed secondary palate has been overstated
Supplemental Material for 'Sea anemones through X-rays : visualization of two species of Diadumene (Cnidaria, Actiniaria) using micro-CT. (American Museum novitates, no. 3907)'
No full textSupplemental Material for 'Sea anemones through X-rays : visualization of two species of Diadumene (Cnidaria, Actiniaria) using micro-CT. (American Museum novitates, no. 3907)
Review of Pattonomys/Toromys clade.
Full text link52 pages : illustrations (some color), map ; 26 cm.New phylogenomic analyses of South American arboreal echimyids show that there are three species within the genus Toromys (T. grandis, T. rhipidurus, and T. sp. nov.) and that the genera Pattonomys and Toromys form a clade that is the sister group to the other three genera of arboreal Echimyini (Echimys, Makalata, and Phyllomys). The arboreal echimyid species Pattonomys occasius is deeply divergent from other species of Pattonomys and from members of other extant named genera, although it shares a sister relationship with Toromys. We erect a new genus, Leiuromys, for it. To clarify the relationships among the species within these three genera, we describe them with molecular and morphological characters. Because most members of these genera have never been reviewed or diagnosed at the species level, we do so now, and we describe a new species, Toromys albiventris, from the upper Ucayali basin of Peru. We illustrate taxa and morphological features not before figured in publications
Dominican Republic fossil Cuban crocodiles.
No full text56 pages : illustrations (chiefly color), maps ; 26 cm.Late Quaternary fossils representing a locally extinct population of the Cuban crocodile (Crocodylus rhombifer) are reported from two underwater caves in the Dominican Republic. A large fossil sample of C. rhombifer, from Oleg's Bat Cave near Bavaro in the southeastern Dominican Republic, consists of four nearly complete skulls, numerous isolated cranial elements and mandibles, and more than 100 postcranial bones representing most of the skeleton. These fossils were collected from a completely submerged portion of the cave at a depth of 11 m and about 100 m from the nearest entrance. A skull, mandibles, and two vertebrae of a Cuban crocodile were also found in a second cave called Ni-Rahu, northeast of Santo Domingo. We identify the fossil crocodile skulls from the Dominican Republic as Crocodylus rhombifer because they share the following characters with modern skulls of C. rhombifer from Cuba (as well as fossil skulls from Cuba, the Bahamas, and Cayman Islands): short, broad, and deep rostrum; large orbits; convex nasals along the midline (midrostral boss); prominent swelling on the lacrimals anterior and medial to the orbits; low but obvious ridges extending anteriorly from the lacrimals to the nasals and posteriorly from the lacrimals to the prefrontals and frontals, outlining a distinct diamond- or rhomboid-shaped structure; strongly concave interorbital region and cranial roof; high, narrow ridges on the internal margins of the orbits, extending from the prefrontals to the frontals and posteriorly to the postorbitals; prominent ridges along the lateral margins of the cranial roof on the postorbitals and squamosals, terminating as noticeable protuberances on the posterolateral corners of the squamosals; premaxillary/maxillary suture on the palate essentially horizontal or transverse to the long axis of the skull at the level of the first maxillary tooth; 13 teeth in the maxilla. Certain aspects of the ecology and anatomy of living Crocodylus rhombifer in Cuba, and carbon isotope data from fossil crocodile bones from both the Dominican Republic and the Bahamas, indicate that the Cuban crocodile is a terrestrially adapted predator. The fossil deposits in Oleg's Bat Cave and other underwater caves in the Dominican Republic lack freshwater vertebrates, such as fish and turtles, but contain abundant samples of hystricognath rodents, small ground sloths, and other terrestrial vertebrates, including large land tortoises, that apparently were the primary prey of the crocodiles. Bats are abundant in the fossil deposits in Oleg's Bat Cave, and may have been an additional food source. Bone collagen from a tibia of C. rhombifer from Oleg's Bat Cave yielded an AMS radiocarbon date of 6460 ±30 ryrBP (equivalent to 7320 to 7430 cal yrBP). The chronology for the local extinction of C. rhombifer in Hispaniola is currently unknown, except to document the presence of this species in the eastern Dominican Republic in the early Holocene. Radiocarbon dates and historical records confirm that Cuban crocodiles survived into the period of European colonization (post-1492) in the Bahamas and on Grand Cayman. The only species of crocodile currently found in Hispaniola, the American crocodile (C. acutus), occurs in coastal marine habitats and in two inland brackish-water lakes: Lago Enriquillo in the Dominican Republic and the nearby Etang Saumâtre in Haiti. C. acutus has no fossil record in Hispaniola or elsewhere in the West Indies, suggesting that this species may be a very recent (late Holocene) immigrant in the Antillean region. Crocodylus rhombifer has one of the most limited geographic ranges of any living crocodylian species, known only from freshwater swamps in south-central Cuba and the Isla de Juventud (Isla de Pinos) off the southwestern coast of Cuba. Locally extinct or extirpated populations of C. rhombifer from fossil deposits in the Dominican Republic, Grand Cayman, and the Bahamas document a considerably wider distribution for this species during the Late Quaternary
A new collared lizard (Tropidurus, Tropiduridae) endemic to the western Bolivian Andes and its implications for seasonally dry tropical forests. (American Museum novitates, no. 3896)
Full text link54 pages : color illustrations, color maps ; 26 cm.In this study we describe Tropidurus azurduyae, a new species of lizard endemic to the Andes. This species is restricted to inter-Andean dry valleys of central and southern Bolivia, within the ecoregion known as Bolivian Montane Dry Forests. It is currently known from the departments of Chuquisaca, Cochabamba, Potosí, and Santa Cruz, where it ranges in elevation from about 1000 to 2800 m. In addition, our analyses of closely related populations of Tropidurus from Argentina, Bolivia, Brazil, and Paraguay revealed undescribed species in central and northeastern Brazil and eastern Bolivia that render T. etheridgei Cei, 1982, paraphyletic. These results underscore the need for a comprehensive revision of peripheral and disjunct populations currently assigned to widely distributed species of Tropidurus. The phylogenetic relationships and distribution patterns of these new taxa concur with recent findings supporting seasonally dry tropical forests and open formations of dry vegetation from South America as distinct biotic units. Furthermore, they offer no support for seasonally dry tropical forests as closely related areas. In line with these discoveries, we refute biogeographic scenarios based exclusively on vicariance to explain the biogeographic history of Tropidurus