Immigration dynamics of tropical and subtropical Southeast Asian limestone karst floras

Ex situ origins and dispersal of taxa have played important roles in the assembly of island-like biodiversity hotspots. Insular limestone karsts in Southeast Asia are hotspots of biodiversity and endemism, but the immigration processes of their unique floras are still poorly known. Here, we used Gesneriaceae as a proxy to investigate the immigration dynamics of tropical and subtropical Southeast Asian karst floras. We present the most comprehensive phylogenetic analysis of the Old World gesneriads to date based on twelve loci. By estimating divergence times and reconstructing ancestral states (habitat, soil type and range), we found that immigration into subtropical Southeast Asian karst floras first occurred in the Early Miocene, with two peaks in the Early–Middle Miocene and the Pliocene–Early Pleistocene, whereas immigration into tropical Southeast Asian karsts initiated in the Late Eocene, with two peaks in the Late Oligocene and the Late Miocene. We also discover that Southeast Asian karst biodiversity comprises immigrant pre-adapted lineages and descendants from local acid soil ancestors, although niche shift from acid soil to karst in tropical Southeast Asian islands was lacking. This study advances our understanding of the historical assembly of Southeast Asian karst floras.

First record of the Sulia glaesaria Simutnik, 2015 (Hymenoptera, Chalcidoidea, Encyrtidae) from Rovno amber

Sulia glaesaria Simutnik, 2015 (Chalcidoidea, Encyrtidae), originally described from late Eocene Danish amber, is reported in coeval Rovno amber. A revised diagnosis of this genus is provided based on the new specimen and high-resolution photomicrographs of the holotype. Some character states, such as a short radicle, clypeus with long lateral margins, the presence of a strigil and basitarsal comb, spur vein of the hind wing, costal cell of hind wing along entire marginal vein with single line of long setae, and almost vertical syntergum with abruptly reflexed extension apically are reported in this species for the first time.

First Paleocene Lepidozona (Mollusca: Polyplacophora: Chitonida) from Ukraine

A new species Lepidozona luzanovkensis sp. nov. from Paleocene deposits of Ukraine is described. This find is much earlier than the known finds from the late Eocene or Early Oligocene, which increases the age of the genus Lepidozona Pilsbry, 1892 by several million years.

An image dataset of cleared, x-rayed, and fossil leaves vetted to plant family for human and machine learning

Leaves are the most abundant and visible plant organ, both in the modern world and the fossil record. Identifying foliage to the correct plant family based on leaf architecture is a fundamental botanical skill that is also critical for isolated fossil leaves, which often, especially in the Cenozoic, represent extinct genera and species from extant families. Resources focused on leaf identification are remarkably scarce; however, the situation has improved due to the recent proliferation of digitized herbarium material, live-plant identification applications, and online collections of cleared and fossil leaf images. Nevertheless, the need remains for a specialized image dataset for comparative leaf architecture. We address this gap by assembling an open-access database of 30,252 images of vouchered leaf specimens vetted to family level, primarily of angiosperms, including 26,176 images of cleared and x-rayed leaves representing 354 families and 4,076 of fossil leaves from 48 families. The images maintain original resolution, have user-friendly filenames, and are vetted using APG and modern paleobotanical standards. The cleared and x-rayed leaves include the Jack A. Wolfe and Leo J. Hickey contributions to the National Cleared Leaf Collection and a collection of high-resolution scanned x-ray negatives, housed in the Division of Paleobotany, Department of Paleobiology, Smithsonian National Museum of Natural History, Washington D.C.; and the Daniel I. Axelrod Cleared Leaf Collection, housed at the University of California Museum of Paleontology, Berkeley. The fossil images include a sampling of Late Cretaceous to Eocene paleobotanical sites from the Western Hemisphere held at numerous institutions, especially from Florissant Fossil Beds National Monument (late Eocene, Colorado), as well as several other localities from the Late Cretaceous to Eocene of the Western USA and the early Paleogene of Colombia and southern Argentina. The dataset facilitates new research and education opportunities in paleobotany, comparative leaf architecture, systematics, and machine learning.

Clusiomitidae, A New Family of Eocene Fossil Acalyptratae, with Revision of Acartophthalmites Hennig and Clusiomites Gen. Nov. (Diptera)

The Eocene Baltic amber fossil flies of the genus Acartophthalmites Hennig, 1965 (Diptera: Acalyptratae) are revised. Seven species are recognized and described or redescribed. Five species, A. crassipes sp. nov., A. luridus sp. nov., A. rugosus sp. nov., A. tertiaria Hennig, 1965 (type species) and A. willii Pérez-de la Fuente, Hoffeins et Roháček, 2018 are retained in Acartophthalmites while Clusiomites gen. nov. is described for two other species, C. clusioides (Roháček, 2016) comb. nov. (type species) and C. ornatus sp. nov. Relationships of these fossil taxa are discussed and, because they cannot be confidently placed in any known family of Diptera, a new family, Clusiomitidae, is established for them. Clusiomitidae is recognized as a family of Opomyzoidea, probably most closely allied to Clusiidae. These results again confirmed that the diversity of acalyptrate flies was very high in the Mid-late Eocene amber forest.

New species of the fossil ant genus Drymomyrmex (Hymenoptera, Formicidae, Formicinae) from the late Eocene Rovno amber (Ukraine)

A new species of the fossil ant genus Drymomyrmex Wheeler, 1915, D. rasnitsyni sp. nov., is described from the late Eocene Rovno amber (Ukraine). This is the first find of a worker of this genus and the first record of Drymomyrmex in the Rovno amber. Based on the analysis of the morphological features of gynes and worker it is proposed to attribute Drymomyrmex to the tribe Plagiolepidini Forel, 1886.

Regional Tectonics to Basin Fill Architecture from Aptian Shuaiba Fm to Miocene Fars Gp of Abu Dhabi

Objectives/Scope Aptian (Shuaiba-Bab) and Cenomanian (Mishrif-Shilaif) intra-shelf basins were extensively studied with their genesis focused on environmental/climatic disturbances (Vahrenkamp et al., 2015a). Additionally, local tectonic events can also affect the physiography of these basins, especially the Cenomanian intra-shelf basin subjected to NE compressional regime. As this ongoing regime increased at Late-Cretaceous and Miocene, it led to more tectonic-driven basin physiography. This paper investigates the areal extent, interaction, and commonalities between the extensional Aptian intra-shelf basin, compressional Late-Cretaceous intra-shelf basin, Late-Cretaceous-Paleogene foreland basin, and Late Oligocene-Miocene salt basin. Methods, Procedures, Process To understand the genesis, driving forces, and distribution of these basins, we used a combination of several large-scale stratigraphic well correlations and seismic, together with age dating, cores, and extensive well information (ADNOC proprietary internal reports). The methodology used this data for detailed mapping of 11 relevant time stratigraphic intervals, placing the mapped architecture in the context of the global eustatic sea level and major geodynamic events of the Arabian Plate. Results, Observations, Conclusions Aptian basin took place as a consequence of environmental/climatic disturbances (Vahrenkamp et al., 2015a). However, environmental factors alone cannot explain isolated carbonate build-ups on salt-related structures at the intra-shelf basin, offshore Abu Dhabi. Subsequently, the emplacement of thrust sheets of Tethyan rocks from NE, and following ophiolite obduction (Searle et al., 1990; Searle, 2007; Searle and Ali, 2009; Searle et al., 2014), established a compressional regime in the Albian?-Cenomanian. This induced tectonic features such as: loading-erosion on eastern Abu Dhabi, isolated carbonate build-ups, and reactivation of a N-S deep-rooted fault (possibly a continuation of Precambrian Amad basement ridge from KSA). This N-S feature was probably the main factor contributing the basin axis change from E-W Aptian trend to N-S position at Cenomanian. Further compression continued into the Coniacian-Santonian, leading to a nascent foreland basin. This compression established a foredeep in eastern Abu Dhabi, separated by a bulge from the northern extension of the eastern Rub’ Al-Khali basin (Ghurab syncline) (Patton and O'Connor, 1988). Numerous paleostructures were developed onshore Abu Dhabi, together with several small patch-reefs on offshore salt growing structures. Campanian exhibits maximum structuration associated to eastern transpression related to Masirah ophiolite obduction during India drift (Johnson et al., 2005, Filbrandt et al., 2006; Gaina et al., 2015). This caused more differentiation of the foredeep, onshore synclines, and northern paleostructures, which continued to cease through Maastrichtian. From Paleocene to Late-Eocene, paleostructure growth intensity continued decreasing and foreland basin hydrological restriction began with the Neotethys closure. Through Oligocene until Burdigalian this situation continued, where the Neotethys closed with the Zagros Orogeny (Sharland et al., 2001), causing a new environmental/climatic disturbances period. These disturbances prevented the continued progradation of the carbonate factory into the foredeep, leading to conspicuous platform-basin differentiation. Additionally, the Zagros orogeny tilted the plate northeastward, dismantling the paleostructures generated at Late-Cenomanian. Finally, during an arid climate in the Burdigalian to Middle-Miocene, the confined Neogene sea filled the foredeep accommodation space with massive evaporites. Novel/Additive Information Little has been published about the outline and architecture of these basins in Abu Dhabi and the detailed circumstances that led to their genesis using subsurface information.

Description and ontogeny of a 40-million-year-old parasitic isopodan crustacean: Parvucymoides dvorakorum gen. et sp. nov.

A collection of exceptionally well-preserved fossil specimens of crustaceans, clearly representatives of Isopoda, is presented here. Excavated from the late Eocene (approximately 40 million years ago) freshwater sediments of the Trupelník hill field site near Kučlín, Czech Republic, these specimens are preserved with many details of the appendages. The morphological characteristics of the fossils were documented using macro-photography with polarised light, as well as stereo imaging. These characteristics, especially including the trunk appendage morphology, were compared to those of related extant groups from different ontogenetic stages. All specimens are conspecific, representing a single species Parvucymoides dvorakorum gen. et sp. nov. Morphometric analysis of body shapes and sizes of the reconstructed fossils and related extant species were performed. These analyses provided insight into the ontogenetic stages of each reconstructed fossil specimen. In combination with the morphological assessment, the results indicate that the fossils represent at least two (possibly three) developmental stages, including immatures. The morphology of the appendages suggests that these fossils were parasites. The fossils are interpreted as either representatives of Cymothoidae or at least closely related to this group.