Cretaceous Burmese Amber Research Articles

Mermithids (Nematoda: Mermithidae) of biting midges (Diptera: Ceratopogonidae): Heleidomermis cataloniensis n. sp. from Culicoides circumscriptus Kieffer in Spain and a species of Cretacimermis Poinar, 2001 from a ceratopogonid in Burmese amber

Heleidomermis cataloniensis n. sp. (Nematoda: Mermithidae) is described from Culicoides circumscriptus Kieffer (Diptera: Ceratopogonidae) in Spain. Diagnostic characters include prominant elevations with multiple genital papillae on either side of the cloacal opening, only one row of genital papillae on the lateral surface of the tail, the tapering tip of the spicule and a reduced vagina. A male intersex of C. circumscriptus parasitised by H. cataloniensis n. sp. has mouthparts resembling those of the female. Two 100 million year-old fossil specimens of an un-named species of Cretacimermis Poinar, 2001, from an Early Cretaceous Burmese amber biting midge of the genus Leptoconops Skuse, show the antiquity of ceratopogonid-mermithid associations.

Vetiplanaxis pyrrhobryoides, a new fossil moss genus and species from Middle Cretaceous Burmese amber

Abstract A moss fossil in Burmese amber is described as a new genus and species, Vetiplanaxis pyrrhobryoides. Previously the specimen was misidentified as Hypnodendron, based partially on a misinterpretation of laminar areolation. The age of the Burmese amber is Middle Cretaceous, not Eocene as previously believed, making this one of the best preserved and potentially most informative moss fossils known from the Mesozoic. The specimen has morphological affinities to some Bryalean and proto-pleurocarpous groups, but cannot be securely placed in any extant family.

Evidence of mycoparasitism and hypermycoparasitism in Early Cretaceous amber

Evidence of mycoparasitism and hypermycoparasitism is demonstrated in Early Cretaceous Burmese amber. The agaric, Palaeoagaracites antiquus gen. sp. nov., is parasitized by the mycoparasite, Mycetophagites atrebora gen. sp. nov., which in turn is parasitized by the hyperparasite, Entropezites patricii gen. sp. nov. This discovery shows that sophisticated patterns of fungal parasitism were well developed some 100 Myrago.

A Fossil Bee from Early Cretaceous Burmese Amber

The bee fossil record is fragmentary, making it difficult to accurately estimate the antiquity of bee-mediated pollination. Here, we describe a bee fossil [Melittosphex burmensis (new species), Melittosphecidae (new family)] from Early Cretaceous Burmese amber (approximately 100 million years before the present). The fossil provides insights into the morphology of the earliest bees and provides a new minimum date for the antiquity of bees and bee-mediated pollination.

Nematode (Nematoda: Mermithidae) and hairworm (Nematomorpha: Chordodidae) parasites in Early Cretaceous amber

The present report describes a mermithid nematode (Nematoda: Mermithidae) and a gordiid hairworm (Nematomorpha: Chordodidae) from Early Cretaceous Burmese amber dated at 100–110 million years. The mermithid, Cretacimermis protus sp. n., is emerging from a biting midge (Diptera: Ceratopogonidae) while the hairworm, Cretachordodes burmitis, gen. n., sp. n. had already emerged from its host. These rare specimens represent the first fossil mermithid parasite of a ceratopogonid midge and second oldest described nematode and the earliest known and only Mesozoic fossil of the phylum Nematomorpha. A list of previously described fossil mermithids is included.

Fossil evidence of insect pathogens

The present report describes fossil evidence of insect pathogens, heretofore, almost non-existent, from six samples of amber ranging in age from 15 to 100 million years. They include a cytoplasmic polyhedrosis virus and trypanosomatid infection in an adult biting midge (Diptera: Ceratopogonidae), and a nuclear polyhedrosis virus in an adult sand fly (Diptera: Phlebotomidae), both from Early Cretaceous Burmese amber, several types of fungal thalli on the cuticle of an adult mosquito (Culicidae: Diptera), as well as a fungal growth on the prothorax of a fungus gnat (Mycetophilidae: Diptera) in Dominican amber and large tumors in the body cavity of a caterpillar (Lepidoptera) in Mexican amber. These discoveries suggest that insect polyhedrosis viruses were present 100 million years ago and present the possibility that vertebrate arboviruses (especially those in the family Reoviridae) could have evolved from cytoplasmic polyhedrosis viruses infecting biting insects. The flagellates in the Early Cretaceous biting midge represent the first fossil record of monogenetic trypanosomatid infections of arthropods.

First identifiable Mesozoic harvestman (Opiliones: Dyspnoi) from Cretaceous Burmese amber

Two inclusions in a piece of Upper Cretaceous (Albian) Burmese amber from Myanmar are described as a harvestman (Arachnida: Opiliones), Halitherses grimaldii new genus and species. The first Mesozoic harvestman to be named can be referred to the suborder Dyspnoi for the following reasons: prosoma divided into two regions, the posterior formed by the fusion of the meso- and metapeltidium; palp lacking a terminal claw, with clavate setae, and tarsus considerably shorter than the tibia. The bilobed, anteriorly projecting ocular tubercle is reminiscent of that of ortholasmatine nemastomatids. The status of other Mesozoic fossils referred to Opiliones is briefly reviewed.

Evidence of Vector-Borne Disease of Early Cretaceous Reptiles

A blood-filled sand fly, Palaeomyia burmitis, was recently described from Early Cretaceous Burmese amber. Within the alimentary canal of this sand fly were the amastigotes and promastigotes of a digenetic leishmanial trypanosomatid. Inside the lumen of the thoracic midgut of the fossil sand fly were nucleated blood cells, some of which were intact and others in various stages of lysis and disintegration. The present study identifies these blood cells as reptilian and describes putative developing amastigotes inside spherical to oval whitish vacuoles within some of the fossil blood cells. The significance of this find is discussed, especially regarding the high possibility that Cretaceous dinosaurs were infected by trypanosomatids.

Paleoleishmania proterus n. gen., n. sp., (Trypanosomatidae: Kinetoplastida) from Cretaceous Burmese Amber

A trypanosomatid (Trypanosomatidae: Kinetoplastida) associated with a blood-filled female sand fly in Cretaceous Burmese amber, is described in the new genus and species, Paleoleishmania proterus. The genus Paleoleishmania is established as a collective genus for digenetic fossil trypanosomes associated with sand flies. Amastigotes, promastigotes and paramastigotes are described. Paleoleishmania proterus is the first fossil kinetoplastid and provides a minimum age for the digenetic Trypanosomatidae. Its discovery indicates that vector-borne pathogens had been established by the Early Cretaceous.

A new genus of hard ticks in Cretaceous Burmese amber (Acari: Ixodida: Ixodidae).

A hard tick larva in Cretaceous Burmese amber is described as Cornupalpatum burmanicum n. g., n. sp. Diagnostic characters include a subcircular body with a marginal groove, 11 festoons, elongate four-segmented palpi with the fourth segment distinct and apical, the absence of an anal groove and eyes, and the presence of claws on palpal segment 3. The last character is unique for all members of the Ixodida, both fossil and extant. Aside from the palpal claws and marginal groove, features of the tick larva closely resemble those of members of the genus Aponomma Neumann 1899, considered one of the most primitive tick lineages today, whose hosts are primarily reptiles.

New Psychodids from the Cretaceous Ambers of Lebanon and France, with a Discussion of <I>Eophlebotomus connectens</I> Cockerell, 1920 (Diptera, Psychodidae)

Two new psychodid flies, Eophlebotomus gezei sp. nov. and E. carentonensis sp. nov., are described from Lebanese and French Lower Cretaceous ambers. They are considered here to form part of the same genus as the Upper Cretaceous Burmese amber, Eophlebotomus connectens Cockerell, 1920. These discoveries allow the description of the antenna and male genitalia of this enigmatic genus. Although the new species of Eophlebotomus share numerous characters with the Phlebotominae, especially the male genital structures, we retain this genus in the stem-group of the Sycoracinae and Trichomyiinae.