Jason A Dunlop

Museum für Naturkunde - Leibniz Institute for Research on Evolution and Biodiversity | MFN · Evolutionary Morphology

Scorpions (Arachnida: Scorpiones) are a diverse and widespread arachnid order with a rich and deep fossil record. Here we review the, sometimes complex, historical development of fossil scorpion higher classification. We present a chronological account of family and genus names, together with an overview of higher taxa as potential clade names. In...

Much of what we know about terrestrial life during the Carboniferous Period comes from Middle Pennsylvanian (~315–307 Mya) Coal Measures deposited in low-lying wetland environments1–5. We know relatively little about terrestrial ecosystems from the Early Pennsylvanian, which was a critical interval for the diversification of insects, arachnids, tet...

The first fossil harvestmen (Arachnida: Opiliones) from the Messel Pit in Hesse, Germany, are described as ? Leiobunum messelense sp. nov. and ? Leiobunum schaali sp. nov. This is the first formal description of fossil harvestmen from the Eocene (ca. 47 Ma) of Messel, and one of the few non-amber records of harvestmen in the Cenozoic. Remarkably, t...

A new genus and species of arachnid (Chelicerata: Arachnida), Douglassarachne acanthopoda n. gen. n. sp., is described from the late Carboniferous (Moscovian) Coal Measures of the Mazon Creek Lagerstätte, Illinois, USA. This is a unique animal with distinctive large spines on the legs. It has a subovate body, a segmented opisthosoma, and a terminal...

Ticks are composed of 3 extant families (Argasidae, Ixodidae and Nuttalliellidae) and 2 extinct families (Deinocrotonidae and Khimairidae). The Nuttalliellidae possess one extant species (Nuttalliella namaqua) limited to the Afrotropic region. A basal relationship to the hard and soft tick families and its limited distribution suggested an origin f...

In this work, we elucidate the taxonomic identity of Opopaea euphorbicola (= O. deserticola Simon, 1892) and designate a neotype to stabilise its taxonomy and nomenclature. We also newly record three other oonopid spiders from Ascension Island. The goblin spiders of Ascension are unremarkable; all constitute non-native and widespread species which...

Historical data, combined with current data on species distribution, are a valuable resource for tracking changes in biodiversity and can potentially be applied to developing models in conservation biology and designing and assessing conservation strategies. Historical data supporting current knowledge on the natural history of the African continen...

Palaeozoic fossils of whip scorpions (Arachnida: Uropygi: Thelyphonida) are extremely rare, with only seven species of this age previously described. A new species of fossil whip scorpion, as well as the first ichnospecies assignable to this group, are described here from the Carboniferous Narragansett Basin of Massachusetts, USA. A body fossil fro...

The extinct arachnid order Trigonotarbida Petrunkevitch, 1949 is reported here for the first time from Ukraine. The material consists of an opisthosoma preserved in ventral view from the upper Carboniferous (lower Moscovian; Paralegoceras-Eowellerites ammonoid zone) of the Gorlivka locality in the Donets Basin, eastern Ukraine. Formal assignment to...

The first Palaeozoic spider (Arachnida: Araneae) from Germany is described as Arthrolycosa wolterbeeki sp. nov. and comes from the late Carboniferous (Moscovian) strata of Piesberg near Osnabrück in Lower Saxony. Characteristic for the genus, the new fossil reveals a posteriorly tuberculate dorsal opisthosoma, and relatively elongate and setose leg...

The first eupnoid harvestmen (Opiliones: Eupnoi) are described from the mid-Cretaceous (ca. 99 Ma) Burmese amber (Kachin State, northern Myanmar). All four living suborders of Opiliones are now known from this amber source. Tyrannobunus aculeus gen. et sp. nov. preserves a unique combination of characters including spiny legs, large eyes in an ante...

The occurrence of Atypus affinis Eichwald, 1830 in Tuscany is confirmed after more than 120 years through a specimen found in Florence. The history of the only record so far available in the literature is also briefly reconstructed, adding the probable year of collecting, after correction of the collector’s name.

Ten new Cyphophthalmi specimens (Arachnida: Opiliones) from the Upper Cretaceous (Lower Cenomanian) Burmese amber of northern Myanmar are described. Seven of these are placed in Stylocellidae, the predominant extant family found today in Southeast Asia. Sirocellus iunctus gen. et sp. nov. represents the first fossil with a combination of sironid an...

Whip scorpions (Thelyphonida) and schizomids (Schizomida) are closely related arachnid orders, whose low species diversity compared to other arachnid groups is reflected in a limited fossil record. Here we investigate two key fossil whip scorpions from the British Middle Coal Measures of Coseley, Staffordshire (late Carboniferous, c. 315 Ma), UK, u...

The brown dog tick Rhipicephalus sanguineus (sensu lato) in the southeastern Mediterranean region and the Middle East is difficult to identify due to the presence of multiple mitochondrial DNA haplogroup lineages. The purpose of this study was to clarify the identity of the “southeastern Europe” lineage of this tick species complex. Our research sh...

Six species of scorpion (Arachnida: Scorpiones) are documented from eighteen localities in seven different states within the Republic of the Sudan. Combining this new data with historical records in the Sudan Natural History Museum and the published literature enables the first provisional distribution maps for Sudanese scorpions. New state records...

Two new laniatoreans from Eocene Baltic amber are described. Baltonychia obscura gen. et sp. nov. represents the first fossil Laniatores with a peltonychium on tarsus III–IV, implying that its closest living relatives are likely members of the extant families Cladonychiidae or Travuniidae. A second fossil is described as Insidiatores indet. as its...

Three examples of metastriate hard ticks (Ixodida: Ixodidae) with apparent affinities to modern Australasian genera are described from the mid-Cretaceous (ca. 100 Ma) Burmese amber of Myanmar. Two nymphs of Bothriocroton muelleri sp. nov. represent the oldest (and only) fossil record of this genus, living members of which are restricted to Australi...

Parvibellus atavus gen. et sp. nov. from the Early Cambrian Chengjiang fauna of China is a small fossil having a distinct cephalic region bearing a pair of lateral projections and a circular, ventral mouth. The trunk bears eleven pairs of probably flap-like appendages and a short pair of terminal projections. This character combination is unique fo...

Four new laniatorean harvestmen specimens (Arachnida: Opiliones: Laniatores) are described from the mid-Cretaceous (upper Albian–lower Cenomanian) Burmese amber of Northern Myanmar. One is placed as Insidiatores indet., but is not formally named as it is probably immature. Burmalomanius circularis n. gen. n. sp. and Petroburma tarsomeria n. gen. n....

Spiders (Araneae) can be placed within a series of nested clades within Arachnida. Arachnopulmonata encompasses all arachnids with book lungs. Pantetrapulmonata encompasses arachnids with four pairs of lungs in their ground pattern. Tetrapulmonata potentially encompasses pantetrapulmonate arachnids which have reduced the number of lateral eye lense...

A new jumping spider (Araneae: Salticidae) is described here based on a well-preserved male from the mid-Miocene Zhangpu biota of southeastern China. We tentatively assign it to an indeterminate position in the subfamily Salticinae. It represents the first salticid in Zhangpu amber and only the second salticid fossil from China. The new specimen ma...

Four fossil ticks (Arachnida: Parasitiformes: Ixodida) are described from mid-Cretaceous (ca. 100 Ma) Burmese amber of Myanmar. Ixodes antiquorum sp. nov. (Ixodidae) is the first Mesozoic record of Ixodes and the oldest representative of the most species-rich extant tick genus. Its affinities appear to lie with modern Australian forms, consistent w...

Parioscorpio venator Wendruff et al., 2020a from the early Silurian Waukesha biota of Wisconsin, USA, interpreted as the earliest scorpion, then a basal euarthropod, is reinterpreted here as a cheloniellid-like arthropod with large raptorial appendages. The diversity of Cheloniellida Broili, 1932 is reviewed. Drabovaspis complexa Chlupáč, 1963, fro...

The stylonurid eurypterid Leiopterella tetliei Lamsdell, Braddy, Loeffler, and Dineley, 2010 (Chelicerata: Eurypterida: Rhenopteridae) from the Early Devonian (Lochkovian) of Nunavut in Arctic Canada is redescribed. Restudy of the holotype under polarized light revealed a labrum, epistomal sutures, prosomal appendage III, and deltoid plates anterio...

We address the taxonomic position of Orthodactylus olivaceus Karsch, 1881, the type species of the genus Orthochirus Karsch, 1892. For over a century, this taxon was considered a synonym of Orthochirus scrobiculosus (Grube, 1873); however, the latter was recently limited to Central Asia (Turkmenistan) (Kovařík et al., 2020). Analysis of Karsch’s ho...

Six species of harvestman (Arachnida: Opiliones) are documented from the Eocene Rovno amber in Ukraine. From the suborder Eupnoi we record Caddo dentipalpus (C. L. Koch & Berendt, 1854) (Caddidae), Amilenus deltshevi Dunlop & Mitov, 2009 (Phalangiidae) and Dicranopalpus ramiger (C. L. Koch & Berendt, 1854) (family incertae sedis). To these we add a...

Among Chelicerata, larval instars of sea spiders (Pycnogonida) can be parasitic. The oldest putative sea spider from the Cambrian ‘Orsten’ is immature and resembles comparable instars of modern species with a parasitic phase to their life cycle. All other parasitic chelicerates are mites, with several examples in both the Acariformes and Parasitifo...

The first pedipalpal regeneration observed in a fossil harvestman (Arachnida: Opiliones) is documented in a specimen of Dicranopalpus ramiger (Koch & Berendt, 1854) from Eocene Baltic amber (ca. 44–49 Ma). The tibia of the right pedipalp is strongly truncated and shorter than the adjacent patella and its apophysis. Possible reasons for this aberrat...

One new family, six new genera and six new species of laniatorean harvestmen (Arachnida: Opiliones: Laniatores) from the mid-Cretaceous (Cenomanian, ca. 99 Ma) Burmese amber of Northern Myanmar are described. Ellenbergellus tuberculatus gen. et sp. nov. is the first fossil assignable to the extant family Tithaeidae. Mesokanus oehmkuehnlei gen. et s...

Eurypterids — Paleozoic ‘sea scorpions’ that could grow several meters long — were thought to have been aquatic. Computer tomography reveals that respiratory organs of a new fossil eurypterid resemble arachnid book lungs, supporting the hypothesis that eurypterids — and perhaps arachnid ancestors — were amphibious.

The first fossil opilioacariform mite (Acari: Opilioacariformes), Paracarus pristinus sp. n., is described from Baltic amber (Tertiary: Eocene). This well-preserved inclusion has six eyes and, thus, can be excluded from the derived, four-eyed genera. Based on characters such as the extremely long leg 4, it is assigned to the extant central Asian ge...

The type material of Chasmataspis laurencii Caster & Brooks, 1956 (Chelicerata: Chasmataspidida) from the Middle Ordovician (Tremadoc to Caradoc) of Sevier County, Tennessee, USA, is redescribed, and comparisons are drawn with recently discovered Devonian chasmataspids from Scotland, Germany and Russia. The depositional setting of the C. laurencii...

The first whipspider (Arachnida: Amblypygi) and three new examples of whipscorpions (Arachnida: Uropygi: Thelyphonida) are described from Lower Cretaceous (Aptian) strata of the Crato Formation, Ceará State, Brazil. The whipspider is described as Britopygus weygoldti gen. et sp. nov. It resembles members of the extant family Charinidae, but cannot...

The Late Carboniferous whip spider Graeophonus anglicus Pocock, 1911 (Arachnida: Amblypygi), is redescribed on the basis of the holotype and nine other specimens all preserved in sideritic nodules from the British Middle Coal Measures of Coseley, Staffordshire, UK. This species is clearly basal with respect to most living whip spiders, expressing n...

Study of abundant phalangiotarbid (Arachnida: Phalangiotarbida) material – provisionally assigned here to Bornatarbus mayasii (Haupt in Nindel 1955) – from the Upper Carboniferous of Writhlington, UK, has revealed new information about some previously equivocal characters. The present authors report a trifurcate apotele, possible spiracles on stern...

A new, exceptionally preserved, trigonotarbid (Arachnida, Trigonotarbida, Palaeocharin‐idae), Palaeocharinus tuberculatus sp. nov. is described from the early Devonian (Pragian) Windyfield chert of Rhynie, Aberdeenshire, Scotland, UK. The specimens found are almost twice the size of previous Rhynie palaeocharinids and display an autapomorphic, micr...

Recently, the Society of Vertebrate Paleontology (SVP) has sent around a letter, dated 21st April, 2020 to more than 300 palaeontological journals, signed by the President, Vice President and a former President of the society (Rayfield et al. 2020). The signatories of this letter request significant changes to the common practices in palaeontology....

Background: Lobopodians are worm-like animals with simple legs. Probably representing a grade of organization, rather than an explicit clade, some lobopodians are thought to have given rise to both Euarthropoda and Onychophora (velvet worms). Another subset has been referred to as gilled lobopodians, and are characterized by flap-like appendages al...

Here, we present the first complete mitochondrial genome of the pentastomid Linguatula arctica collected from the nasal passages of a reindeer (Rangifer tarandus) in Norway. The full length mitochondrial genome of L. arctica, which measures 14,789 bp in length, contains 13 protein-coding genes, 2 ribosomal RNA genes and 22 transfer RNA genes. A cle...

Amber from the Bitterfeld area in Germany is a significant source of paleobiological data for the Paleogene of central Europe. Rich invertebrate communities have been preserved in this amber but most species remain to be documented and described. In this study, we provide the rst inventory of the pseudoscorpion fauna from Bitterfeld amber. All avai...

Arachnids are an ancient lineage of arthropods and orders such as scorpions, harvestmen and mites have their fossil origins in the Silurian or Devonian. Another order with potentially old origins is the short-tailed whipscorpions, or schizomids (Arachnida: Schizomida). These animals have a fragmentary fossil record with species either described or...

Most knowledge about the structure, function, and evolution of early compound eyes is based on investigations in trilobites. However, these studies dealt mainly with the cuticular lenses and little was known about internal anatomy. Only recently some data on crystalline cones and retinula cells were reported for a Cambrian trilobite species. Here,...

Most knowledge about the structure, function, and evolution of early compound eyes is based on investigations in trilobites. However, these studies dealt mainly with the cuticular lenses and little was known about internal anatomy. Only recently some data on crystalline cones and retinula cells were reported for a Cambrian trilobite species. Here,...

Literature-based species lists for arachnids, excluding spiders and mites, found in the Republic of the Sudan are provided. We summarize records, references, and localities for 17 scorpions (Scorpiones), one harvestman (Opiliones), nine pseudoscorpions (Pseudoscorpiones), 21 camel spiders (Solifugae) and one whip spider (Amblypygi). There are no pu...

Arachnids and their relatives (Chelicerata) range in body length from tens of centimetres in horseshoe crabs down to little more than 80-200 μm in several groups of mites. Spiders (Araneae) show the widest range within a given Bauplan - the largest species being ca. 270 times longer than the smallest - making them excellent models to investigate sc...

An unusually large acariform mite is described as Immensmaris chewbaccei gen. et sp. nov. from the Cretaceous (ca. 100 Ma) Burmese amber of Myanmar. With an idiosoma plus gnathosoma more than a centimetre long, it represents the largest unequivocal fossil mite ever recorded and approaches the maximum size of the largest living Acariformes today. Al...

The Acari (mites) is currently interpreted to consist of two superorders. In contrast to the relatively rich history of the mite superorder Acariformes, fossils of the Parasitiformes are extremely rare. This is especially true of the most diverse order, Mesostigmata, with only nine families recorded, including four named species, having been descri...

The rapid rise of arthropods during the Cambrian quickly established some clades, such as the euarthropod stem-group called Radiodonta, as the dominant and most diverse predators in marine ecosystems. Recent discoveries have shown that the size and dietary ecology of radiodontans is far more diverse than previously thought, but little is known abou...

The first fossil potentially assignable to the extant hard tick genus Haemaphysalis CL Koch (1844) (Ixodida: Ixodidae) is described from the Late Cretaceous (ca. 99 Ma) Burmese amber of Myanmar. Haemaphysalis ( Alloceraea ) cretacea sp. nov. is the oldest and only fossil representative of this genus; living members of which predominantly feed on ma...

The Chengjiang fossil Lagerstätte (Cambrian Stage 3) from Yunnan, southern China is renowned for its soft-tissue preservation. Accordingly structures in fuxianhuiids, radiodontans and great appendage arthropods have been interpreted as the nervous and cardiovascular systems, including brains, hearts and blood vessels. That such delicate organ syste...

Spiders (Araneae) are a hugely successful lineage with a long history. Details of their origins remain obscure, with little knowledge of their stem group and few insights into the sequence of character acquisition during spider evolution. Here, we describe Chimerarachne yingi gen. et sp. nov., a remarkable arachnid from the mid-Cretaceous (approxim...

Bitterfeld amber, sometimes referred to as Saxon or Saxonian amber, is a potentially significant but poorly known source of arthropod data for the Palaeogene of northern Europe. An important aspect is a long-standing controversy about the age of this amber: namely whether it is equivalent to, and perhaps merely a southerly extension of, the better-...

The Early Devonian Rhynie and Windyfield cherts remain a key locality for understanding early life and ecology on land. They host the oldest unequivocal nematode worm (Nematoda), which may also offer the earliest evidence for herbivory via plant parasitism. The trigonotarbids (Arachnida: Trigonotarbida) preserve the oldest book lungs and were proba...

Background: Arachnids are a highly successful group of land-dwelling arthropods. They are major contributors to modern terrestrial ecosystems, and have a deep evolutionary history. Whip spiders (Arachnida, Amblypygi), are one of the smaller arachnid orders with ca. 190 living species. Here we restudy one of the oldest fossil representatives of the...

The affinities and status of all known fossil whip spiders (Arachnida: Amblypygi) from the Coal Measures of Europe and North America are revised. Graeophonus carbonarius () from Cape Breton in Canada is based on an isolated insect or arachnid abdomen; and both the species and genus names (Graeophonus) are regarded here as nomina dubia. A second spe...

The present work offers records of six species of spiders (Arachnida: Araneae) from three localities in the eastern part of the Republic of the Sudan. Three represent new species records for the country. Artema kochi (Kulczyński, 1901) (Pholcidae) was collected in New Halfa in Kassala State. Pardosa observans (O. Pickard-Cambridge, 1876) (Lycosidae...

Pseudoscorpions, given their resemblance to scorpions, have attracted human attention since the time of Aristotle, although they are much smaller and lack the sting and elongated tail. These arachnids have a long evolutionary history but their origins and phylogenetic affinities are still being debated. Here, we summarise their fossil record based...

Amblyomma birmitum sp. nov. is formally described as a new record from 99 Ma old Burmese amber from Myanmar. This confirms the presence of the extant hard tick genus Amblyomma C.L. Koch, 1844 (Ixodida: Ixodidae) in the Late Cretaceous. This discovery is placed in its wider context and some reports of fossil hard ticks, such as a Hyalomma C.L. Koch,...

An annotated catalogue of the type and non-type scutigeromorph centipedes (Chilopoda: Scutigeromorpha) held in the Museum für Naturkunde Berlin is presented. The collection includes material from throughout the world, with a focus on former German colonies. Notes on collectors and localities are provided where appropriate. Type material for 42 Rece...

We present the first complete mitochondrial genome of the pentastomid Armillifer grandis (Arthropoda: Pentastomida) collected from the lungs of a rhinoceros viper (Bitis nasicornis) in the Democratic Republic of Congo. The full length mitochondrial genome of Armillifer grandis, which measures 16,073 bp in length, contains 13 protein-coding genes, 2...

A second camel spider (Arachnida, Solifugae) from the Late Cretaceous (c. 99 Ma) Burmese amber of Myanmar is described. It is referred to Cushingia cf. ellenbergeri Dunlop et al., 2015. This extinct species is of uncertain familial affinities, but noticeable are similarities to the modern genus Dinorhax Simon, 1879, which is today the only camel sp...

Background Fossil ticks are extremely rare and Ixodes succineus Weidner, 1964 from Eocene (ca. 44–49 Ma) Baltic amber is one of the oldest examples of a living hard tick genus (Ixodida: Ixodidae). Previous work suggested it was most closely related to the modern and widespread European sheep tick Ixodes ricinus (Linneaus, 1758). Results Restudy us...

The distribution of lateral eyes in arachnids and their relatives (Chelicerata) is reviewed, including novel data for selected taxa. Particular focus was given to camel spiders (Solifugae) and whip scorpions (Thelyphonida), for which there are conflicting reports about their eye morphology in the literature, and to the condition in some fossil scor...

Background: Paleozoic scorpions (Arachnida: Scorpiones) have been widely documented from the Carboniferous Period; which hosts a remarkable assemblage of more than sixty species including both putative stem- and crown-group fossils. By contrast the succeeding Permian Period is almost completely devoid of records, which are currently restricted to...