Palaeoentomology

Steinkern spiders: A microbial mat-controlled taphonomic pathway in the Oligocene Aix-en-Provence Lagerstätte, France

2022-08-30T03:09:06+12:00

The Aix-en-Provence Formation is an Oligocene (22.5 Ma) Lagerstätte in southern France that contains an abundance of soft-bodied fossils preserved in exceptional detail. Many taxa have been described from this formation, including insects, spiders, fishes, and plants, suggesting a diverse ecosystem in a subtropical, brackish, lacustrine paleoenvironment. Fossil spiders from this deposit are preserved as compression fossils and internal and external molds. Recently, compression fossils of spiders from Aix-en-Provence were hypothesized to be a product of a taphonomic pathway based on diatoms and sulfurization. Here, we examine fossil spiders preserved as molds to uncover a second taphonomic pathway based on microbial mats. Evidence of microbial mats include wrinkles, pustular textures, and possible microbial mat chips on the bedding surfaces as well as a matrix fabric that contains possible microbial sheaths and bacterial spherules. The evidence presented here supports prolific microbial mat communities during deposition of the Aix-en-Provence Formation, and suggests that they are likely responsible for the moldic preservation of the spiders. Our work shows that the paleoenvironment of the Aix-en-Provence Formation promoted at least two possible taphonomic pathways that resulted in the differing modes of preservation observed.

Revision of the two small damselflies Eopodagrion scudderi Cockerell, 1921 and Eopodagrion ‘Podagrion’ abortivum (Scudder, 1878) (Odonata, Zygoptera) from the lower Eocene of Green River Formation (USA)

2022-08-23T02:35:21+12:00

Two early Eocene damselfly taxa Eopodagrion scudderi Cockerell, 1921 and Eopodagrion ‘Podagrion’ abortivum (Scudder, 1878) are redescribed and refigured. Their phylogenetic relationships are discussed. Although they could likely belong to the Coenagrionidae, their exact affinities remain uncertain because of the presence of homoplasies affecting crucial characters among the Zygoptera.

Parelateriformius from the Middle–Late Jurassic of China reinterpreted as the earliest Dascillidae (Coleoptera: Dascilloidea)

2022-11-25T11:51:13+13:00

The elateriform genus Parelateriformius Yan & Wang from the Middle–Late Jurassic Daohugou beds has been placed previously in the extinct Lasiosynidae or the extant Eulichadidae. Our reinvestigation of the type specimens and additional materials suggests that the character combination of Parelateriformius (e.g., tarsomeres 2–4 distinctly lobed, posterior pronotal margin crenulate, radial cell short and with truncate base, and metakatepisternal suture complete) is not accordant with either Lasiosynidae or Eulichadidae. Instead, it should belong to the family Dascillidae and appears closely related to the extant Petalon. A new species of Parelateriformius is also described, as P. grimaldii Li & Cai sp. nov. Our discovery highlights the antiquity of Dascillidae, which is consistent with the recent fossil-calibrated molecular dating of beetles.

Libanonemopalpus grimaldii, a new genus and species of Bruchomyiinae from Lower Cretaceous Lebanese amber (Diptera: Psychodidae)

2022-11-25T19:32:37+13:00

Libanonemopalpus grimaldii gen. et sp. nov. is characterised, illustrated, and described from the lower Barremian amber of Bqaatouta (Lebanon). It represents the earliest record, the first and only Bruchomyiinae psychodid with functional piercing mouthparts. The discovery of this Cretaceous psychodid fly improves our knowledge of the palaeobiodiversity of Bruchomyiinae and particularly on the evolution of mouthparts in this group.

**First record and two new species of the genus Trichomyia (Diptera: Psychodidae) from the Lower Miocene Dominican amber**

2022-12-09T16:56:32+13:00

Trichomyia (Septemtrichomyia) grimaldii sp. nov. and Trichomyia (Trichomyia) fudalai sp. nov. from the Lower Miocene Dominican amber are characterised, described, illustrated and their taxonomic position discussed. These fossils constitute the first record of the Trichomyiinae and increase the knowledge on the biodiversity of the biological inclusions from the Dominican amber. Chresonymy and subgeneric division of the genus Trichomyia are presented and briefly discussed.

The first Archijassidae from the Middle Triassic of China (Hemiptera, Cicadomorpha, Membracoidea)

2022-12-09T16:49:33+13:00

Eocicadellium grimaldii gen. et sp. nov., the oldest representative and first Triassic member of the subfamily Karajassinae Shcherbakov, 1992, is described on the basis of six forewings from the Middle-Upper Triassic Yanchang Formation of northern China, widening the duration and biogeographic distribution of this extinct subfamily. The new data represents the first known definite record of Karajassinae in China, and further explores the palaeodiversity of Triassic archijassids.

A new species of Trichopolydesmidae (Myriapoda, Diplopoda, Polydesmida) from the mid-Cretaceous Burmese amber

2022-12-14T21:28:45+13:00

A new species of the ‘flat-backed’ millipede family Trichopolydesmidae, Monstrodesmus grimaldii sp. nov., is described from the mid-Cretaceous Burmese amber. Detailed morphological characters are provided on the basis of three well-preserved adults (two males and one female), one male juvenile, and seven additional specimens, using confocal laser scanning microscopy (CLSM) and microcomputer tomography (μCT) with computer-aided 3D-reconstructions. The new species can be placed most likely in the extant genus Monstrodesmus by presenting great similarities to living species.

A new species of Protopsyllidioidea from Cretaceous amber

2022-12-20T15:24:34+13:00

With new fossils of Protopsyllidioidea discovered from amber, our knowledge of the biodiversity in the superfamily increases, and so does our understanding of the evolution of suborder Sternorrhyncha and its ‘basal’ groups. The new species Burmapsyllidium grimaldii Hakim, Azar & Huang sp. nov., assigned to the family Paraprotopsyllidiidae, is reported from the mid-Cretaceous Burmese amber, and described and illustrated.

**Revision of the damselfly Hesperagrion praevolans (Odonata, Zygoptera, Coenagrionidae) from the uppermost Eocene of Florissant (Colorado, USA)**

2022-08-24T01:43:11+12:00

The damselfly family Coenagrionidae is rather frequently found in the Cenozoic fossil record (Nel & Paicheler, 1993), but it remains unknown in the Mesozoic. The known fossils are generally isolated wings, very difficult to accurately attribute to precise genera, to the point that many fossils can be only considered as ‘genera and species undetermined’ (Nel et al., 1997). The oldest described coenagrionid fossil is the late Palaeocene Marado marado Petrulevičius, 2021 (Maíz Gordo Formation, Argentina), a genus and species based on an isolated incomplete wing. Thus, other Eocene representatives of the family are important for future accurate dating of the occurrence of the family and its subdivisions, especially those that have been attributed to extant genera; a future step after the important work of Dijkstra et al. (2014) for the understanding of the evolution of these damselflies.

**The second European representative of the epallagid genus Labandeiraia in the lowermost Eocene Oise amber (Odonata, Zygoptera)**

2022-10-22T15:57:04+13:00

Among the calopteran damselflies, the family Epallagidae was clearly dominating the diversity of the Holarctic Cenozoic (11 described species in eight extinct genera), while the Calopterygidae were extremely rare at the same time (six Cenozoic species in two extant and one fossil genera) (Fossilworks database at http://www.fossilworks.org/cgi-bin/bridge.pl?action=home, consulted 21/10/2022). They mainly belonged to the extinct subfamily Eodichrominae Cockerell, 1923, and their most diverse genus was the early Eocene genus Labandeiraia Petrulevičius et al., 2007, known from compression fossils from the lacustrine Green River Formation (USA) and the marine Fur Formation in Denmark (Petrulevičius et al., 2007; Bechly et al., 2020).

Fossils and flies: Continued contributions celebrating David A. Grimaldi

2022-12-21T13:12:17+13:00

David Grimaldi—appreciations

2022-12-15T18:26:58+13:00

The previous issue of Palaeoentomology brought the first set of papers honoring David A. Grimaldi on the occasion of his 65^th birthday. With the current one, it is continued, in recognition of his impact on the fields of amber studies, palaeontology, palaeo- and neoentomology, and evolutionary biology. After the success of Jurassic Park (both the Michael Crichton book from 1990 and the Steven Spielberg movie from 1993) everyone wants to know more know about the miracles of long ago that are encapsulated in petrified resin. Amber: window to the past (Grimaldi, 1996) originally published to accompany a 1996 exhibition at the American Museum of Natural History in New York, explored the properties of amber and revealed its role in tracing evolutionary history and its use in the decorative arts and jewelry. This surge in interest in amber and palaeoentomology resulted the establishment of the International Palaeoentomological Society in 2001 at the Second International Congress on Palaeoentomology—Fossil Insects, and particularly the study of insect inclusions in amber from various parts of the world. An essential reference for anyone interested in the study of amber fossils, insect evolution, and the earliest stages of the association between insects and angiosperms devoted to amber from New Jersey and edited by Grimaldi (2000), provided an incredibly vivid window into animal and plant evolution in the Late Cretaceous. Another book—Evolution of the insects (Grimaldi & Engel, 2005)—is the first comprehensive synthesis of all aspects of insect evolution integrating the living and fossil record. The book was a great source of information about what we know at the time of its publication, but also highlighted what we do not know, making the book a great source of inspiration for subsequent studies.