The fossil dragonfly Burmalindenia imperfecta gen. et sp. nov. is described from mid-Cretaceous Burmese amber as the first record of the odonate suborder Anisoptera for this locality and one of the ...few records from amber in general. The inclusion comprises two fragments of the two hind wings of a dragonfly. The fossil can be attributed to a new genus and species of the family Gomphidae, presumably in the subfamily Lindeniinae, and features a strange teratological phenomenon in its wing venation.
Epicaridea is an ingroup of Isopoda that comprises only parasitic crustaceans. Within parasitic isopods, epicarideans represent a special case: throughout their ontogeny they switch from a small ...intermediate host (copepod) to a final host (various larger crustaceans), and develop through distinct larval phases (epicaridium, microniscium and cryptoniscium). Young males of some species retain a larval morphology. Recent findings of fossil epicarideans in amber from the Miocene of Mexico consisted in the only epicaridean body fossils, until one specimen has been figured from Cretaceous amber from France. Here we provide a detailed analysis of this specimen and 20 more specimens from the same locality. The presented specimens represent the oldest occurrence of epicaridean body fossils, extending their fossil record by 67 million years.The fossils are exceptionally well preserved and, despite their small size of less than 0.5 mm, reveal even fine morphological details. The specimens correspond either to cryptoniscium larvae or males that have retained their larval morphology. There are no morphological features in the fossils that argue against conspecifity of all specimens. All character states found in the fossils are also present in extant species. Given the displayed combination of character states and the age difference, it is unlikely that the specimens are conspecific to any extant species nor to much younger fossils from the Miocene of Mexico. The species Vacuotheca dupeorum gen. et sp. nov. is described and interpreted as an epicaridean of uncertain affinities, but that is not part of the epicaridean ingroup Dajidae. Furthermore, multiple aspects of the evolutionary history of parasitic isopods and epicarideans in particular are discussed. This includes possible scenarios for host changes that could have led to the life cycle of modern epicarideans and the evolution of size within epicaridean larvae
The fossil record of Isopoda includes remains of presumed parasites. Among the fossils which have been discussed as potential parasites are those termed as Urda Münster, 1840. Some of these fossils ...have been discussed as possibly related to an extant group of parasites, Gnathiidae Leach, 1814. The type species of Urda – Urda rostrata Münster, 1840 – is herein interpreted as a close relative of the group Gnathiidae, based on the shared occurrence of a number of apomorphic features. This is with Urda punctata (Münster, 1842) herein being interpreted as a junior subjective synonym of U. rostrata. However, not all of the fossils associated with the name Urda can safely be identified as close relatives of Gnathiidae. Moreover, it is unclear whether the extinct species, which can be identified as close relatives of U. rostrata and Gnathiidae form a monophyletic group, as we could not identify an autapomorphy for a natural group Urda. A new species of close relatives of Urda rostrata and Gnathiidae – Urda buechneri n. sp. – is formally described based on μCT image data. Palaega suevica Reiff, 1936 and Palaega kessleri Reiff, 1936 are found to be subjective synonyms and are re-interpreted as Urda suevica n. comb. – a species closely related to U. rostrata. Due to the documented destruction of the holotype, a herein figured fossil specimen is designated as the neotype of Urda suevica. Palaega? stemmerbergensis Malzahn, 1968 is also interpreted as a close representative of U. rostrata and herein treated as Urda stemmerbergensis n. comb. Another already formally described species – Eobooralana rhodanica gen. et comb. nov. – is interpreted as a more distant relative, which is likely to be closer related to other extant species of Isopoda than those within Gnathiidae. For three species there are not enough characters preserved to interpret them as closely related to U. rostrata and Gnathiidae: Urda? liasica Frentzen, 1937 nom. dub. (type material destroyed, description insufficient for proper diagnosis), Urda? moravica Remeš, 1912 and Urda? zelandica Buckeridge and Johns, 1996.
El registro fósil de Isopoda incluye restos de posibles parásitos. Entre los fósiles que han sido discutidos como parásitos potenciales se encuentra Urda Münster, 1840. Algunos de estos fósiles han sido discutidos como posibles parientes de un grupo existente de parásitos, los Gnathiidae Leach, 1814. La especie tipo de Urda - Urda rostrata Münster, 1840 - es aquí interpretada como pariente cercano del grupo Gnathiidae, con base en la presencia común de un número de caracteres apomórficos. Esto incluye a Urda punctata (Münster, 1842) interpretada aquí como sinónimo junior subjetivo de U. rostrata. Sin embargo, no todos los fósiles asociados con el nombre Urda pueden ser indudablemente identificados como parientes cercanos a Gnathiidae. De manera adicional, no es aún claro si las expecies extintas, que podrían ser identificadas como cercanas a U. rostrata y Gnathiidae, forman un grupo monofilético, dado que no podemos identificar alguna autapomorfía para un grupo natural Urda. Una nueva especie de parientes cercanos a Urda rostrata y Gnathiidae - Urda buechneri n. sp. - es descrita formalmente con base en datos de imágenes μCT. Palaega suevica Reiff, 1936 y Palaega kessleri Reiff, 1936 son interpretados como sinónimos subjetivos y reinterpretados como Urda suevica n. comb. - como especies cercanamente relacionadas a U. rostrata. Debido a la documentada destrucción del holotipo, un ejemplar fósil aquí ilustrado, es designado como el neotipo de Urda suevica. Palaega? stemmerbergensis Malzahn, 1968 es también interpretada como como pariente cercano a U. rostrata y es tratada aquí como Urda stemmerbergensis n. comb. Otra especie ya descrita formalmente - Eobooralana rhodanica gen. et comb. nov. - es interpretada como un pariente más distante, quien probablemente se encuentra relacionada a otra especie viviente de Isopoda, que con los Gnathiidae. No existen caracteres suficientes preservados para tres especies, a fin de interpretarlas como cercanamente relacionadas a U. rostrata and Gnathiidae: Urda? liasica Frentzen, 1937 nom. dub. (material tipo destruído, descripción insuficiente para una adecuada diagnosis), Urda? moravica Remeš, 1912 y Urda? zelandica Buckeridge y Johns, 1996.
Anhelkocephalon handlirschi Bill, 1914 has been described as a representative of Isopoda (woodlice and relatives). Fossils of A. handlirschi come from the Grès à Voltzia Formation in western France, ...close to the German border. The Grès à Voltzia Formation (Voltziensandstein) is Triassic in age; lithostratigraphically, it belongs to the Buntsandstein Group. Based on the morphology of the type material and one additional specimen, we interpret A. handlirschi not as a representative of Isopoda, but as a representative of Cyclida. Cyclida is an extinct group of Euarthropoda, the representatives of which have a circular to oval outline of the body (in dorsal view). One of the herein studied specimens has aspects of appendage morphology preserved, which, in general, is a rare case for cyclidans. The herein studied specimens also add new features to the knowledge about the morphology of Cyclida, such as a net-like pattern on the dorsal body side.
Within Isopoda (woodlice and relatives), there are lineages characterised by a parasitic lifestyle that all belong to Cymothoida and likely form a monophyletic group. Representatives of Epicaridea ...(ingroup of Cymothoida) are parasitic on crustaceans and usually go through three distinct larval stages. The fossil record of Epicaridea is sparse and thus little is known about the palaeoecology and the origin of the complex life cycle of modern epicarideans. We present an assemblage of over 100 epicarideans preserved in a single piece of Late Cretaceous Myanmar amber. All individuals are morphologically similar to cryptoniscium stage larvae. The cryptoniscium stage usually constitutes the third and last larval stage. In modern representatives of Epicaridea, the cryptoniscium larvae are planktic and search for suitable host animals or adult females. These fossil specimens, though similar to some extant species, differ from other fossil epicaridean larvae in many aspects. Thus, a new species (and a new genus),
Cryptolacruma nidis
, is erected. Several factors can favour the preservation of multiple conspecific animals in a single piece of amber. However, the enormous density of epicarideans in the herein presented amber piece can only be explained by circumstances that result in high local densities of individuals, close to the resin-producing tree.
The earliest known fossil beetle † Coleopsis archaica is re-examined using Reflectance Transformation Imaging (RTI). The morphological observations are evaluated with respect to phylogenetic ...implications and the early evolution of Coleoptera . † Coleopsis archaica belongs to an early Permian branch of beetles, outside a monophyletic unit comprising Coleoptera (in the widest sense) excluding † Tshekardocoleidae . This clade is mainly characterized by a complex of apomorphic features: elytra with epipleura and with a close fit with the posterior body, thus forming a tightly sealed subelytral space. In contrast to this, the elytra of † C. archaica and † Tshekardocoleidae cover the metathorax and abdomen in a loose tent-like manner and posteriorly distinctly surpass the abdominal apex. So far, no synapomorphies of the two taxa from the first half of the Permian have been identified. The very short and transverse pronotum is likely an autapomorphy of † C. archaica. A thorough documentation of the structural features of early beetle fossils should have high priority. RTI is a very promising tool to obtain new and well-founded morphological data, which will allow a thorough phylogenetic evaluation of Permian beetles in future studies. We extended the conventional RTI workflow by focus merging and panoramic stitching, in order to overcome previous limitations. Taxonomic re-arrangements of stem group beetles including † C. archaica were suggested in recent studies by A.G. Kirejtshuk and co-workers. As they are not based on shared derived features they are irrelevant in a phylogenetic and evolutionary context.
Thylacocephala is a group of extinct eucrustaceans of presumably predatory nature. We describe here a new genus and species of thylacocephalan crustaceans from the Upper Jurassic Solnhofen limestones ...of Eichstätt (Altmühltal Formation), Falcatacaris bastelbergeri n. g. n. sp. (about 150 million years old). Falcatacaris bastelbergeri n. g. n. sp. is the fourth species of Thylacocephala found in these deposits. The species differs significantly from other thylacocephalans, especially by characters of the shield. The shield of the specimen is rather low (short in dorsoventral extent) and it bears a long rostrum but no elongated posterior spine. For comparative purposes, we provide an overview of the shield morphology of known thylacocephalan species from literature as well as a morphological analysis of the group. An elliptic Fourier analysis is used to compare the different shield shapes of thylacocephalans to each other; results are presented in PCA plots. Shield length and anterior or posterior shield extensions are the characters with the most variation in thylacocephalan shield morphology.
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