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Brachycera in Cretaceous amber, part 9.
Full text link97 pages : illustrations (some color) ; 26 cm.Diverse new basal (aschizan) Cyclorrhapha fossilized in amber are described from the Tertiary and Cretaceous, and their relationships are examined with character-based phylogenetic hypotheses for each family or family group. There are 18 new species in 15 genera (11 of them new) and four families plus the Syrphoidea. Fossils are from the Early Cretaceous of Lebanon, Late Cretaceous of New Jersey (United States) and Alberta (Canada), Eocene of the eastern Baltic coast, and Miocene of the Dominican Republic, but predominantly from the mid-Cretaceous of Myanmar. Stem-group Lonchopteroidea are Alonchoptera lebanica, n. gen., n.sp., and Lonchopterites burmensis, n. sp. Platypezidae include the stem groups Burmapeza radicis, n. gen., n. sp., Canadopeza biacrosticha, n. gen., n. sp., and Calvopeza divergens, n. gen., n. sp. An unnamed Microsania sp. is the first definitive Platypezidae in Baltic amber; Lebanopeza azari, n. gen., n. sp., is a stem group to the Microsaniinae and Melanderomyiinae. Chandleromyia anomala, n. gen., n. sp., is an anomalously derived Platypezinae from the Cretaceous, and two new species of the diverse Recent genus Lindneromyia are in Dominican amber (L. neomedialis and L. dominicana). Fossils of the relict family Ironomyiidae (with 3 living species from eastern Australia) include two stem-group genera with two new species each, all in Burmese amber: Palaeopetia dorsalis and P. terminus, Proironia (n. gen.) gibbera and P. burmitica. All other species of Palaeopetia are compression fossils from the Cretaceous of Asia and Eurasia. For Phoridae, a new defining feature is a stridulatum on the procoxa and profemur in both sexes, occu[r]ring in most fossil taxa where observable. New sciadocerines include Eosciadocera pauciseta, n. sp., a very large species in Baltic amber, and two stem groups in Burmese amber, Prophora dimorion, n. gen., n. sp., and a very small, undescribed taxon. Archiphora pria Grimaldi and Cumming in Turonian-aged New Jersey amber is transferred to Hennigophora Brown, based on evidence from a new specimen. Prioriphorinae (not taxonomically treated here) is a paraphyletic, Cretaceous grade to the very diverse, crown-group radiation of Euphorida that occurred in the Cenozoic. Two syrphoids occur in Burmese amber: Prosyrphus thompsoni, n. gen., n. sp. (an apparent stem group to the Syrphidae), and Aschizomyia burmensis, n. gen., n. sp. (with more ambiguous affinities). Several immatures of undetermined family are reported, one a probable phorid larva. No definitive Schizophora are yet known from the Cretaceous
New Paleogene notohippids and leontiniids (Toxodontia, Notoungulata, Mammalia) from the early Oligocene Tinguiririca Fauna of the Andean Main Range, central Chile. (American Museum novitates, no. 3903)
Full text link42 pages : illustrations ; 26 cm.Here we describe three new notohippid notoungulate species from the early Oligocene-aged Tinguiririca Fauna (Tinguirirican SALMA), recovered from volcaniclastic deposits of the Abanico Formation in the central Chilean Andes, two of which are known from material sufficiently complete to warrant formal naming. These include Eomorphippus bondi, sp. nov., a form of moderate size distinguished by hypsodont incisors and cheekteeth, as well as distinctive proportions of the upper incisors. A closely similar but more diminutive form is described as Eomorphippus neilopdykei, sp. nov. A third previously unrecognized notohippid in the Tinguiririca Fauna, best represented by a large, low-crowned, lower incisor battery, almost certainly represents a new taxon, but remains too fragmentary to warrant naming now. We also propose a new binomial for a previously named notohippid, ?Eomorphippus pascuali, originally described from Gran Barranca in Argentina but which is now also recorded in Chile. This taxon, here named Rosendo pascuali, is markedly less hypsodont than E. bondi and E. neilopdykei and retains lingual cingula on at least p4-m1. As least one leontiniid notoungulate occurs in the Tinguiririca Fauna, Termastherium flacoensis, gen. et sp. nov., best represented by two partial upper cheek toothrows and a tentatively referred maxillary fragment bearing three deciduous teeth. Collectively, description of these new fossils from Termas del Flaco, Chile helps to more fully characterize the Tinguiririca Fauna, facilitating correlation and comparison to other South American land mammal faunas spanning the Eocene-Oligocene transition
Puyehuemyia chandleri, gen. nov., sp. nov. (Diptera, Opetiidae) : remnant of a Cretaceous biota in Chile. (American Museum novitates, no. 3892)
Full text link27 pages : illustrations (chiefly color) ; 26 cm.The first Opetiidae known from the Southern Hemisphere is described--Puyehuemyia chandleri, gen. nov., sp. nov.--based on a female specimen collected in Valdivian forest in the Province of Osorno, south Chile. The Palearctic species Opetia nigra Meigen was also studied, allowing detailed comparisons. Features of the antenna, mouthparts, wing, and terminalia allowed the issue of the position of the family within the Eremoneura to be revisited. The inclusion of Opetiidae in the Platypezoidea is corroborated, possibly in a clade also including Lonchopteridae and Phoridae. The 3-articled condition of the styluslike arista in Puyehuemyia corroborates the hypothesis that the 2-articled condition in Opetia is independently derived, as it is in the Empidoidea and many schizophorans. Puyehuemyia chandleri has female terminalia typical of parasitoid groups, as does Opetia, although their life history is not known. Described Platypezoidea Cretaceous amber fossils are reviewed, and Lonchopterites is considered to be sister to the crown group of Opetiidae. The presence of an Early Cretaceous biogeographical layer in the Valdivian forest, associated with plant and animals disjunct from New Zealand, and similar to the beech forests in the Northern Hemisphere, is discussed
Nesting biologies of oxaeine bees.
Full text link31 pages : illustrations (some color) ; 26 cm. "Appendix: Postdefecating larva of the cleptoparasitic bees Thalestria spinosa (Fabricius) and Triepeolus kathrynae Rozen (Apidae, Nomadinae, Epeolini)": pages 28-31.This study encompasses a number of field encounters by the author and others with nests of representatives of three of the four genera of the little-known New World andrenid subfamily Oxaeinae. Species treated include Protoxaea gloriosa Fox, Oxaea flavescens Klug, O. austera Gerstaecker, and Mesoxaea nigerrima (Friese), leaving the nesting biology of only the monotypic genus Notoxaea completely unknown. Nests, all subterranean, are described and diaƠgrammed, and each is reported to consist of a moderately to very deep main burrow with vertical cells occurring at the lower end attached to the main burrow by subhorizontal lateral tunnels, each of which is closed immediately after egg deposition. To the extent known, eggs, mature larvae, and pupae are described. Two known cleptoparasites of the subfamily are reported: Triepeolus kathrynae Rozen, hosted by P. gloriosa, and Thalestria spinosa (Fabricius) (= T. smaragdina Smith), which attacks nests of both O. flavescens and O. austera. The mature larvae of these cleptoparasitic Nomadinae are described and illustrated as an appendix
A new species of Forstercooperia (Perissodactyla, Paraceratheriidae) from northern China with a systematic revision of forstercooperiines. (American Museum novitates, no. 3897)
Full text link41 pages : illustrations (chiefly color), color map ; 26 cm.Forstercooperiines are a group of large, primitive rhinocerotoids that are commonly regarded as ancestral to later giant rhinos. However, the type genus of forstercooperiines, the Middle Eocene Forstercooperia, is one of the most poorly known rhinocerotoids, and is represented only by fragmentary material. Here we name a new species, Forstercooperia ulanshirehensis, based on five specimens, including a well-preserved cranium and a pair of complete mandibles. This new material was collected from the Ulan Shireh Formation in the western part of the Erlian Basin and the Irdin Manha Formation in the eastern part of the Erlian Basin, northern China. These specimens provide the most complete craniodental remains of Forstercooperia sensu stricto (excluding Pappaceras), and on this basis the species-level taxonomy of forstercooperiines is thoroughly revised and six species of two genera are considered as valid. Specimens previously assigned to "Forstercooperia minuta" are reassigned to different species based on the revised diagnoses. All equivocal specimens that were thought to have an affinity with Forstercooperiinae are briefly discussed. Based on a new character matrix, phylogenetic analyses fully resolve the relationships of early rhinocerotoids, including the recovery of Forstercooperia and Pappaceras as sister groups. The occurrence of Forstercooperia ulanshirehensis in the eastern and western Erlian Basin is indicative of age correlation between the lower part of the Ulan Shireh Formation and the Irdin Manha Formation
A second specimen of Citipati osmolskae associated with a nest of eggs from Ukhaa Tolgod, Omnogov Aimag, Mongolia. (American Museum novitates, no. 3899)
Full text link44 pages : illustrations (chiefly color) ; 26 cm.
Specimen discovered during the 1995 installment of the American Museum of Natural History-Mongolian Academy of Sciences Paleontological Expedition.Adult dinosaurs preserved attending their nests in brooding positions are among the rarest vertebrate fossils. By far the most common occurrences are members of the dinosaur group Oviraptorosauria. The first finds of these were specimens recovered from the Djadokhta Formation at the Mongolian locality of Ukhaa Tolgod and the Chinese locality of Bayan Mandahu. Since the initial discovery of these specimens, a few more occurrences of nesting oviraptors have been found at other Asian localities. Here we report on a second nesting oviraptorid specimen (IGM 100/1004) sitting in a brooding position atop a nest of eggs from Ukhaa Tolgod, Omnogov, Mongolia. This is a large specimen of the ubiquitous Ukhaa Tolgod taxon Citipati osmolskae. It is approximately 11% larger based on humeral length than the original Ukhaa Tolgod nesting Citipati osmolskae specimen (IGM 100/979), yet eggshell structure and egg arrangement are identical. No evidence for colonial breeding of these animals has been recovered. Reexamination of another "nesting" oviraptorosaur, the holotype of Oviraptor philoceratops (AMNH FARB 6517) indicates that in addition to the numerous partial eggs associated with the original skeleton that originally led to its referral as a protoceratopsian predator, there are the remains of a tiny theropod. This hind limb can be provisionally assigned to Oviraptoridae. It is thus at least possible that some of the eggs associated with the holotype had hatched and the perinates had not left the nest
Chlorocyon phantasma, a late Eocene borhyaenoid (Mammalia, Metatheria, Sparassodonta) from the Los Helados locality, Andean Main Range, central Chile. (American Museum novitates, 0003-0082 ; no. 3918)
No full text22 pages : illustrations (some color), map ; 26 cm.Sparassodont metatherians were the dominant terrestrial mammalian predators during South America's long Cenozoic isolation. This group's early fossil record is very poor, however, particularly for the late Eocene and early Oligocene. Here, we describe a new sparassodont, Chlorocyon phantasma, gen. et sp. nov., based on a specimen from Los Helados, a new locality within the Abanico Formation of the Andean Main Range of central Chile. New ⁴⁰Ar/³⁹Ar dates at Los Helados bracketing the fossil-bearing level constrain the age of this specimen to 37-36 Ma (late Eocene), indicating that this new taxon likely pertains to the Mustersan South American Land Mammal "Age." Chlorocyon is the first Paleogene sparassodont reported from Chile and the first sparassodont described from the Abanico Formation. Distinctive features, including a p3 with an anterior edge that is more curved than the posterior edge and the lack of a hypoconulid on m4, suggest that Chlorocyon is a borhyaenoid closely related to Pharsophorus or Plesiofelis, although much smaller. Chlorocyon represents a welcome addition to the sparse record of late Eocene sparassodonts and indicates that the diversity of non-proborhyaenid borhyaenoids prior to the late Oligocene was greater than previously thought
A new species of Eumanota Edwards (Diptera, Mycetophilidae, Manotine) from Colombia : evidence for a pseudogondwanan pattern. (American Museum novitates, no. 3915)
No full text19 pages : illustrations (chiefly color) ; 26 cm.Eumanota wolffae, sp. nov., is described from the high Andean forests of Colombia. This is the first Neotropical species of the clade of non-Manota genera of the mycetophilid subfamily Manotinae--to date known entirely from the Oriental and the northwestern Australasian regions, and in Baltic amber. With the other species of Eumanota Edwards, this species shares, among other features, a largely developed third maxillary palpomere, projecting beyond the base of fourth palpomere, with a wide sensorial pit, a flat inner face, and the last palpomere at least 4x the length of the fourth palpomere. The systematic position of the Colombian species within the Manotinae is addressed. The biogeographic significance of Eumanota in the Neotropical region is discussed, interpreted here as a concurrent incidence of a circumtropical pattern and Gondwanan distributions, in other words, a particular pattern of biogeographic pseudocongruence, referred to here as a "pseudogondwanan pattern." This pattern is associated with an early Cenozoic tropical biota over Laurasian terranes that expanded its distribution to the south (in the Americas, Africa, and Australasia), followed by large-scale extinction of Nearctic and Palearctic representatives due to global cooling in the Neogene. A discussion is provided about the correlation between these patterns and evidence of Late Cretaceous-Paleogene tropical floras over Laurasian terranes
Dipleura dekayi.
Full text link8 pages : illustrations, map ; 26 cm.A large and almost complete dorsal exoskeleton of a homalonotid trilobite from the Middle Devonian of Colombia (Floresta Formation) is described and referred to Dipleura dekayi Green, 1832, confirming prior suggestions of biogeographical affinity between Colombia and the North Eastern Americas Realm during Devonian times
