FIGURE 3 - uploaded by Paul A Selden
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Seppo koponeni n. gen. & n. sp. Holotype and only known specimen MB.A 2966. A, cheliceral furrow showing base of fang and row of ?promarginal peg teeth. B, distal end of metatarsus I, retrolateral, showing bristle-like macrosetae and trichobothrium, and pedipalp tarsus showing toothed terminal claw. C, metatarsus of right leg IV, prolateral, showing rows of bristles and distal pair of curved bristles. All photographs taken under 70% ethanol and in cross-polarized light.
Source publication
The first Lower Jurassic (Lias) spider is described as Seppo koponeni n. gen. & n. sp. from a single female specimen from Grimmen, Germany. It most likely belongs to the Palpimanoidea, on account of the presence of cheliceral peg teeth and other features consistent with palpimanoid families, though its familial placement is uncertain. Its presence...
Contexts in source publication
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... Pomerania, Germany (Ansorge 1996(Ansorge , 2007. The preservation is curious, being one of only a few examples of spiders preserved in calcium carbonate (another is the Late Eocene Insect Limestone of the Isle of Wight, England: Selden 2001Selden , 2014. Some parts are preserved as external moulds, and these show setation and spination (e.g. Fig. 3C). Most of the specimen, however, is an internal mould of calcium carbonate. This presents the animal nicely in three dimensions, but lacks external cuticular features except at the edges where setae and similar structures, preserved as organic material, can be seen protruding into the adjacent matrix (Fig. 3B). The contrast can be seen ...
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... show setation and spination (e.g. Fig. 3C). Most of the specimen, however, is an internal mould of calcium carbonate. This presents the animal nicely in three dimensions, but lacks external cuticular features except at the edges where setae and similar structures, preserved as organic material, can be seen protruding into the adjacent matrix (Fig. 3B). The contrast can be seen most clearly in the comparison of right (internal mould) and left (external mould) chelicerae (Figs ...
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... a foramen. The cheliceral furrow bears no true teeth, but a row of stiff, socketed bristles, apparently on the promargin. Because they would perform the function of true teeth, these are interpreted as peg teeth, although they are not so strong and lack the boss-like bases commonly seen in archaeids, for example. About six peg teeth are visible ( Fig. 3A) and the bases of another six or so can also be seen; a few fine hairs also occur more proximally along the furrow; the external mould of the left chelicera shows scattered setae. The sternum is visible; it has a straight anterior border where it abuts the labium (there is a sharp demarcation where the labium is oriented upwards), ...
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... is that this fragment belongs to the tarsus of right leg I, by extrapolation making the leg an altogether much longer appendage, but this seems less likely. Bristles (thin macrosetae) and setae are numerous, where preserved, on the podomeres. In particular, there are rows on femora to tarsi, seen best on right leg I tibia and metatarsus (Fig. 3B), left leg II femur and tibia, and right leg IV metatarsus (Fig. 3C). A trichobothrium can be seen distally on right leg I metatarsus (Fig. 3B). Legs IV show a slight, but distinct, mesial curvature (Figs 1, 2) The opisthosoma is preserved as a subcircular patch of dark organic matter, lacking relief, and with a scattering of bristles ...
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... by extrapolation making the leg an altogether much longer appendage, but this seems less likely. Bristles (thin macrosetae) and setae are numerous, where preserved, on the podomeres. In particular, there are rows on femora to tarsi, seen best on right leg I tibia and metatarsus (Fig. 3B), left leg II femur and tibia, and right leg IV metatarsus (Fig. 3C). A trichobothrium can be seen distally on right leg I metatarsus (Fig. 3B). Legs IV show a slight, but distinct, mesial curvature (Figs 1, 2) The opisthosoma is preserved as a subcircular patch of dark organic matter, lacking relief, and with a scattering of bristles within and extending beyond the dark area. The dark area is presumed ...
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... this seems less likely. Bristles (thin macrosetae) and setae are numerous, where preserved, on the podomeres. In particular, there are rows on femora to tarsi, seen best on right leg I tibia and metatarsus (Fig. 3B), left leg II femur and tibia, and right leg IV metatarsus (Fig. 3C). A trichobothrium can be seen distally on right leg I metatarsus (Fig. 3B). Legs IV show a slight, but distinct, mesial curvature (Figs 1, 2) The opisthosoma is preserved as a subcircular patch of dark organic matter, lacking relief, and with a scattering of bristles within and extending beyond the dark area. The dark area is presumed to be ventral, on account of the preservation of the rest of the spider ...
Citations
... For the remainder of the manuscript, when we refer to Palpimanoidea this is done with the exclusion of †Lagonomegopidae. Within Palpimanoidea, the earliest diverging branch is a group consisting of the oldest fossils from the Jurassic: †Seppo, †Onychopalpus, and †Sinaranea (73% SH-alrt and 88% UFBoot), the first from Germany (Selden and Dunlop, 2014), and the latter 2 from Inner Mongolia (Selden et al. 2008(Selden et al. , 2020. Palpimanidae plus †Cretapalpus, all southern, was monophyletic (100% SH-alrt and UFBoot) and diverged next. ...
... Spiders are ancient, with an estimated age of around 400 Ma (Magalhães et al. 2020), creating challenges in recovering deep phylogenetic relationships. Palpimanoidea is also an ancient group considering the oldest fossils are from the Jurassic (Selden et al. 2008(Selden et al. , 2020Selden and Dunlop 2014). The value of incorporating fossils in this situation, which necessitates the use of morphological data, is that fossils often have intermediate or transitional traits that can inform phylogenetic reconstruction. ...
Burmese amber is a significant source of fossils that documents the mid-Cretaceous biota. This deposit was formed around 99 Ma on the Burma Terrane, which broke away from Gondwana and later collided with Asia, although the timing is disputed. Palpimanoidea is a dispersal-limited group that was a dominant element of the Mesozoic spider fauna, and has an extensive fossil record, particularly from Burmese amber. Using morphological and molecular data, evolutionary relationships of living and fossil Palpimanoidea are examined. Divergence dating with fossils as terminal tips, followed by ancestral range estimations, shows timing of diversification is contemporaneous with continental break-up and that widespread ancestral ranges divide into lineages that inherit different Pangean fragments, consistent with vicariance. Our results suggest that the Burmese amber fauna has ties to Gondwana due to a historical connection in the Early Cretaceous, and that the Burma Terrane facilitated biotic exchange by transporting lineages from Gondwana into the Holarctic in the Cretaceous.
... The age of this species was set to between 15 and 20 Myr according to the most accepted age for Dominican amber (see Iturralde-Vinent and MacPhee, 1996). Other fossil terminals were selected following the list of oldest spider fossils per clade by Magalhaes et al., (2020a), and include: the sister group of all spiders, Chimerarachne yingi Wang et al., 2018 (98-99 Myr, see Wang et al., 2018); the oldest Mesothelae, Palaeothele montceauensis (Selden, 1996) (299-304 Myr, see Selden, 1996; the oldest Mygalomorphae, Rosamygale grauvogeli Selden & Gall, 1992(242-247 Myr, see Selden & Gall, 1992; the oldest Palpimanoidea, Seppo koponeni Selden and Dunlop, 2014 (173-183 Myr, see Selden and Dunlop, 2014); the oldest stem Synspermiata, Eoplectreurys gertschi Selden and Huang, 2010 (164-175 Myr, see Selden and Huang, 2010); the oldest crown Synspermiata, Montsecarachne amicorum Selden, 2014(125-129, see Selden, 2014; and one of the oldest confirmed oecobiids, Zamilia quattuormammillae Wunderlich, 2015 (98-99 Myr; see Wunderlich, 2015). Fossils in the outgroup were scored from the images and descriptions in their original publications, which also include detailed information about the age, horizon and specimens examined by the original authors. ...
Filistatids, the crevice weavers, are an ancient family of cribellate spiders without extant close relatives. As one of the first lineages of araneomorph spiders, they present a complicated mixture of primitive and derived characters that make them a key taxon to elucidate the phylogeny of spiders, as well as the evolution of phenotypic characters in this group. Their moderate diversity (187 species in 19 genera) is distributed mainly in arid and semi‐arid subtropical zones of all continents, except Antarctica. The objective of this paper is to generate a comprehensive phylogenetic hypothesis for this family to advance the understanding of its morphological evolution and biogeography, as well as lay the basis for a natural classification scheme. By studying the morphology using optical and electronic microscopy techniques, we produced a matrix of 302 morphological characters coded for a sample of 103 species of filistatids chosen to represent the phylogenetic diversity of the family. In addition, we included sequences of four molecular markers (COI, 16S, H3 and 28S; 3787 aligned positions) of 70 filistatid species. The analysis of the data (morphological, molecular, and combined) consistently indicates the separation of the Filistatidae into two subfamilies, Prithinae and Filistatinae, in addition to supporting several groups of genera: Filistata, Zaitunia and an undescribed genus from Madagascar; Sahastata and Kukulcania; all Prithinae except Filistatinella and Microfilistata; Antilloides and Filistatoides; a large Old World group including Pritha, Tricalamus, Afrofilistata, Labahitha, Yardiella, Wandella and putative new genera; and a South American group formed by Lihuelistata, Pikelinia and Misionella. Pholcoides is transferred to Filistatinae and Microfilistata is transferred to Prithinae, and each represents the sister group to the remaining genera of its own subfamily. Most genera are valid, although Pikelinia is paraphyletic with respect to Misionella, so we consider the two genera as synonyms and propose a few new generic combinations. Considering the new phylogenetic hypothesis, we discuss the evolution of some morphological character systems and the biogeography of the family. The ages of divergence between clades were estimated using a total‐evidence tip‐dating approach by including fossils of Filistatidae and early spider clades; this approach resulted in younger age estimates than those obtained with traditional node‐dating. Filistatidae is an ancient family that started diversifying in the Mesozoic and most genera date to the Cretaceous. Clades displaying transcontinental distributions were most likely affected by continental drift, but at least one clade shows unequivocal signs of transoceanic long‐distance dispersal.
... A comparison of the mineralogical attributes of the bones indicate that the gravisaurian remains probably do not originate from the horizon with insect-bearing carbonate concretions of the "Green Series" clay of exaratum subzone, contradicting Stumpf et al. (2015). In addition to the terrestrial tetrapods, the presence of abundant insects (Ansorge 1996(Ansorge , 2003) and a single spider (Selden & Dunlop 2014) indicates a rather short distance to the mainland or certain islands. A possible source might be the Arkona high (an island in the extension of the Ringköping-Fyn high to the southeast; Seidel 2019), rather than the more distal Scandinavian mainland. ...
Thyreophora is a clade of globally distributed herbivorous ornithischian dinosaurs. The earliest forms are known from the Early Jurassic, and their latest surviving representatives witnessed the end-Cretaceous mass extinction. Throughout their evolutionary history, these ‘shield bearers’ became lumbering quadrupeds, evolved a wide array of bony armor, plates and spikes, as well as sweeping tail weapons in the form of tail clubs and thagomizers. An isolated new thyreophoran osteoderm from a Lower Jurassic Konservatlagerstätte near Grimmen is described and, with the aid of micro-CT data, compared to an osteoderm of the early diverging thyreophoran Emausaurus ernsti from a different stratigraphic horizon at the same locality.
... It is the oldest member of the family and the first Mesozoic record; the previously known oldest, and only known fossil occurrence of Palpimanidae, are three juvenile specimens of the extant genus Otiothops MacLeay, 1839 from the Neogene Dominican amber (Wunderlich 1988); a possible palpimanid has also been reported from mid-Cretaceous Burmese amber (Wunderlich 2017). Nevertheless, the superfamily Palpimanoidea has representatives dating back to the Jurassic period (Penney 2004;Selden et al. 2008;Selden & Dunlop 2014;Wunderlich 2015;Selden et al. 2019 and references therein), so the existence of the nominate family in the early Cretaceous is not improbable. Palpimanoidea, especially the family Archaeidae, has received much more attention in phylogenetic studies. ...
The Crato Formation (Lower Cretaceous) of Brazil is well known for an exceptionally preserved terrestrial arthropod fossil assemblage. Spiders are relatively abundant, but few have been formally described. A fossil spider belonging to the family Palpimanidae, araneophageous ground-dwelling spiders with distinctly robust front legs, is preserved with the dorsal side hidden within the rock matrix. For the first time, micro-computed tomography (micro-CT) was used to image a fossil spider preserved in a rock matrix, to reveal the dorsal side of this specimen, revealing the eye arrangement, a useful taxonomic character in most spiders, and a deflated abdomen, likely the result of taphonomic processes. The specimen possesses other distinguishing characteristics of Palpimanidae, including an inflated first leg femur, a heavily sclerotized scutum, and a reduced number of spinnerets (2) surrounded by a sclerotized ring. The spider has eight eyes with the lateral pairs extremely close together, a trait suggestive of the subfamily Chediminae. The specimen also possesses an unusual first leg patella with a retrolateral excavation and a thorn-like projection. A new genus is erected, and the spider is named Cretapalpus vittari gen. et sp. nov. A phylogenetic analysis including extant species from each of the subfamilies within Palpimanidae places the fossil at the base of Chediminae + Otiothopinae. This is the earliest reported fossil palpimanid and first chedimine from South America. A fossil chedimine in South America is not surprising because the South American and African plates were still relatively close during the Early Cretaceous.
... Thus, either S. koponeni is either a stem Palpimanoidea or (less likely) a stem Entelegynae, and it is safe to use its age as a minimum bound for the age of Palpimanoidea + Entelegynae. Location and age: Klein Lehmhagen clay pit, Grimmen, Vorpommern, Germany; Toarcian, at least 173.1 Mya (Selden & Dunlop, 2014). ...
Studies in evolutionary biology and biogeography increasingly rely on the estimation of dated phylogenetic trees using molecular clocks. In turn, the calibration of such clocks is critically dependent on external evidence (i.e. fossils) anchoring the ages of particular nodes to known absolute ages. In recent years, a plethora of new fossil spiders, especially from the Mesozoic, have been described, while the number of studies presenting dated spider phylogenies based on fossil calibrations increased sharply. We critically evaluate 44 of these studies, which collectively employed 67 unique fossils in 180 calibrations. Approximately 54% of these calibrations are problematic, particularly regarding unsupported assignment of fossils to extant clades (44%) and crown (rather than stem) dating (9%). Most of these cases result from an assumed equivalence between taxonomic placement of fossils and their phylogenetic position. To overcome this limitation, we extensively review the literature on fossil spiders, with a special focus on putative synapomorphies and the phylogenetic placement of fossil species with regard to their importance for calibrating higher taxa (families and above) in the spider tree of life. We provide a curated list including 41 key fossils intended to be a basis for future estimations of dated spider phylogenies. In a second step, we use a revised set of 23 calibrations to estimate a new dated spider tree of life based on transcriptomic data. The revised placement of key fossils and the new calibrated tree are used to resolve a long‐standing debate in spider evolution – we tested whether there has been a major turnover in the spider fauna between the Mesozoic and Cenozoic. At least 17 (out of 117) extant families have been recorded from the Cretaceous, implying that at least 41 spider lineages in the family level or above crossed the Cretaeous–Paleogene (K–Pg) boundary. The putative phylogenetic affinities of families known only from the Mesozoic suggest that at least seven Cretaceous families appear to have no close living relatives and might represent extinct lineages. There is no unambiguous fossil evidence of the retrolateral tibial apophysis clade (RTA‐clade) in the Mesozoic, although molecular clock analyses estimated the major lineages within this clade to be at least ∼100 million years old. Our review of the fossil record supports a major turnover showing that the spider faunas in the Mesozoic and the Cenozoic are very distinct at high taxonomic levels, with the Mesozoic dominated by Palpimanoidea and Synspermiata, while the Cenozoic is dominated by Araneoidea and RTA‐clade spiders.
... During this century, many more specimens of spiders have been described from the Jurassic Haifanggou Formation of China (Selden et al. 2008(Selden et al. , 2011(Selden et al. , 2013(Selden et al. , 2016Selden & Huang 2010), including palpimanoids, plectreurids and deinopoids. Also, a possible uloborid was described from the Upper Jurassic Talbragar Fossil Fish Bed of New South Wales, Australia, and a palpimanoid from the Early Jurassic (lower Toarcian) of Grimmen, Germany, was described by Selden & Dunlop (2014). This brings the number of described spider species from Jurassic strata to 10, though others await description from the Jurassic beds of China. ...
... For example, there is an undescribed palpimanid from the Cretaceous of Brazil (Selden & Penney 2017, fig . 16), and the palpimanoid Seppo koponeni Selden & Dunlop, 2014, from the Jurassic of Germany, which do not show extreme adaptations. Palpimanids avoid defensive reactions from their high-risk spider prey by having a thick cuticle, and another family of predominantly spider predators, the mimetids, bear long, strong macrosetae on leg I that are used to hold prey firmly (P ekar et al. 2011). ...
Several new spider specimens, belonging to the superfamily Palpimanoidea, are described from the Middle–Upper Jurassic Haifanggou Formation (early assemblage of the Yanliao Biota) of Inner Mongolia, China. Two new genera and species, and a new species in the genus Sinaranea Selden, Huang & Ren, 2008 Selden, P. A. Huang, D.-Y. & Ren, D. 2008. Palpimanoid spiders from the Jurassic of China. Journal of Arachnology, 36, 306–321.[Crossref], [Web of Science ®] , [Google Scholar], are described. Caestaranea jurassica gen. et sp. nov. is described on the basis of several adult males, typified by boxing-glove shaped pedipalps, as well as females and juveniles. Onychopalpus thomisoides gen. et sp. nov. is the largest palpimanoid known, and its habitus resembles that of a crab spider (Thomisidae) in having large, laterigrade anterior legs with rows of macrosetae on the femora and a squat, rotund opisthosoma. However, the distinctive adult male pedipalp bears a pectinate claw, so the holotype specimen is a subadult male; the other specimens referred to this species are smaller juveniles. Three new specimens of Sinaranea metaxyostraca Selden, Huang & Ren, 2008 Selden, P. A. Huang, D.-Y. & Ren, D. 2008. Palpimanoid spiders from the Jurassic of China. Journal of Arachnology, 36, 306–321.[Crossref], [Web of Science ®] , [Google Scholar], including two adult males, are described here, and the new species S. brevicrus sp. nov., which has shorter legs than the type species, is described from an adult male and an adult female. These new palpimanoids substantially increase the diversity of the superfamily in the Middle Jurassic, and the unusual Onychopalpus provides evidence for a different mode of life for these spiders.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:D7726F4B-349E-4C2B-960D-371C27A6B77F
... These faunal elements occur alongside an extraordinarily rich terrestrial entomofauna (Ansorge, 1996(Ansorge, , 2003, indicating the presence of suitable environments nearby. The 'Green Series' of Grimmen has also yielded abundant plant and wood remains, as well as the first Early Jurassic spider and basal sauropod dinosaur remains (Ernst, 1967;Selden and Dunlop, 2014;Stumpf et al., 2015) that were washed into the transepicontinental shelf sea, suggesting a nearshore depositional environment, as proposed by Ernst (1967Ernst ( , 1991 and Ansorge (2003). ...
A new genus and species of pycnodontiform fishes, Grimmenodon aureum, from marginal marine, marine-brackish lower Toarcian (Harpoceras exaratum ammonite subzone) clay deposits of Grimmen in northeastern Germany is described. The single specimen represents a diagnostic left prearticular dentition characterized by unique tooth arrangement and ornamentation patterns. Grimmenodon aureum, gen. et sp. nov., is the second unambiguously identified pycnodontiform species from the Early Jurassic, in addition to Eomesodon liassicus from the early Lower Jurassic of western Europe. We also report an indeterminate pycnodontiform tooth crown from the upper Pliensbachian (Pleuroceras apyrenum ammonite subzone) of the same site. The material expands the Early Jurassic range of pycnodontiforms significantly northwards and confirms their presence before and immediately following the onset of the Toarcian Oceanic Anoxic Event (T-OAE) in the marginal marine ecosystems south of the Fennoscandian Shield. Moreover, the new records indicate that the Early Jurassic diversity of pycnodontiform fishes was greater than previously assumed and probably equaled that of the Late Triassic. Therefore, it is hypothesized that the Triassic-Jurassic mass extinction event did not affect pycnodontiform fishes significantly. Micro-computed tomography was used to study the internal anatomy of the prearticular of Grimmenodon aureum, gen. et sp. nov. Our results show that no replacement teeth were formed within the tooth-bearing bone but rather were added posteriorly to functional teeth.
http://zoobank.org/urn:lsid:zoobank.org:pub:A56BDE9C-40C4-4CFA-9C2E-F5FA35A66F2
Citation for this article: Stumpf, S., J. Ansorge, C. Pfaff, and J. Kriwet. 2017. Early Jurassic diversification of pycnodontiform fishes (Actinopterygii, Neopterygii) after the end-Triassic extinction event: Evidence from a new genus and species, Grimmenodon aureum. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2017.1344679.
... In this region, the lower Toarcian crops out only in the Pleistocene dislocated deposits of Grimmen and Dobbertin (Mecklenburg-Western Pomerania), both exposing a thick package of pure clay, referable to as the "Green Series". Although these clay deposits have been studied for more than a century (e.g., Geinitz 1880Geinitz , 1884Geinitz , 1894Jaekel 1925;ernst 1967, 1992an-sorGe 1996an-sorGe , 2007selden & dunlop 2014;stumpF et al. 2015), the marine reptile material thoroughly studied so far is limited to two ichthyosaur specimens coming from the "Green Series" of Dobbertin. The first mention of ichthyosaur remains from the lower Toarcian "Green Series" clay deposits of Dobbertin was given by Geinitz (1900a, b) who notes the presence of four articulated caudal centra. ...
The marine lower Toarcian (Early Jurassic) formations outcropping in Europe are widely known to have produced diverse faunas of secondarily marine reptiles, especially coming from black bituminous shales and marlstones of Western Europe. Conversely, little attention has been paid to marine reptile material recovered from time-equivalent beds of North-Eastern Germany due to the scarcity of productive localities. Here, a previously undescribed marine reptile assemblage comprising ichthyosaur, plesiosaur and thalattosuchian crocodyliform remains from the marine marginal lower Toarcian (the Harpoceras falciferum ammonite Zone) "Green Series" of North-Eastern Germany is reported, complementing previous records of these groups from Northern Germany with an early Toarcian age. Although fragmentary and largely indeterminate, this material is significant in indicating the presence of a probable new and unnamed ichthyosaur taxon. Moreover, the marine reptile material described herein is significant because it includes the first reliable report of both plesiosaurs and thalattosuchian crocodyliforms from the lower Toarcian of North-Eastern Germany, confirming their presence in this region during Toarcian times.
... Since then, many more spiders have turned up in Cretaceous strata , but there are still relatively few from rocks of Jurassic age. The only known specimen from the Lower Jurassic (Lias), from Grimmen, Germany, has been identified as a palpimanoid (Selden & Dunlop 2014). A possible uloborid was described from the Jurassic Talbragar Fish Bed, Australia, by Selden & Beattie (2013). ...
This study describes a new spider with the most numerous specimens (c. two-thirds) known from the Middle Jurassic Jiulongshan Formation of Daohugou, China, as Zhizhu daohugouensis gen. et sp. nov, together with a related form from the Early Cretaceous Yixian Formation of Huangbanjigou, Zhizhu jeholensis sp. nov., and another, unnamed, specimen known only from an immature female from Daohugou. These spiders are all placed in the stem-Deinopoidea. Two recent studies of the phylogeny of spiders using phylogenomics have shown that deinopoids may be closer to non-orb-weaving cribellates than to ecribellate orbicularians, and that if the evolution of the orb web is a unique event, then it occurred deeper in time, perhaps among early Mesozoic cribellates such as these. The new spiders described here contribute to knowledge of the biodiversity and palaeoecology of the forested lake margins of the North China Block in mid-Mesozoic times.
