Spirochete and protist symbionts of a termite (Mastotermes electrodominicus) in Miocene amber. (1/41)

Extraordinary preservation in amber of the Miocene termite Mastotermes electrodominicus has led to the discovery of fossil symbiotic microbes. Spirochete bacteria and wood-digesting protists were identified in the intestinal tissue of the insect. Fossil wood (xylem: developing vessel-element cells, fibers, pit connections), protists (most likely xylophagic amitochondriates), an endospore (probably of the filamentous intestinal bacterium Arthromitus = Bacillus), and large spirochetes were seen in thin section by light and transmission electron microscopy. The intestinal microbiota of the living termite Mastotermes darwiniensis, a genus now restricted to northern Australia, markedly resembles that preserved in amber. This is a direct observation of a 20-million-year-old xylophagus termite fossil microbial community.  (+info)

Description of Pintomyia (Pifanomyia) Falcaorum sp. n. (Diptera: Psychodidae: Phlebotominae), a fossil sand fly from dominican amber. (2/41)

A new species of sand fly, Pintomyia (Pifanomyia) falcaorum is described from an amber originated from the northern mountain range of Dominican Republic. The male sand fly specimen is well preserved and most features used in Phlebotominae taxonomy are seen with remarkable clarity.  (+info)

Extinction and biogeography in the Caribbean: new evidence from a fossil riodinid butterfly in Dominican amber. (3/41)

We describe a new species of extinct riodinid butterfly, Voltinia dramba, from Oligo-Miocene Dominican amber (15-25 Myr ago). This appears to be the first butterfly to be taxonomically described from amber, and the first adult riodinid fossil. The series of five specimens represents probably the best-preserved fossil record for any lepidopteran. The phenomenon of extant Voltinia females ovipositing on arboreal epiphytes probably explains the discovery of multiple female V. dramba specimens in amber. Voltinia dramba appears to be one of many extinct butterfly species on Hispaniola. The northwestern Mexican distribution of the explicitly hypothesized sister species, the extant V. danforthi, supports the hypothesis that V. dramba reached Hispaniola by the 'proto-Greater Antillean arc', dating the divergence of V. dramba and V. danforthi to 40-50 Myr ago. This date is contemporaneous with the oldest known butterfly fossils, and implies a more ancient date of origin for many of the higher-level butterfly taxa than is often conceded.  (+info)

Ancient genes of Saccharomyces cerevisiae. (4/41)

Amber is a plant resin mainly produced by coniferous trees that, after entrapping a variety of living beings, was subjected to a process of fossilization until it turned into yellowish, translucent stones. It is also one of the best sources of ancient DNA on which to perform studies on evolution. Here a method for the sterilization of amber that allows reliable ancient DNA extraction with no actual DNA contamination is described. Working with insects taken from amber, it was possible to amplify the ATP9, PGU1 and rRNA18S ancient genes of Saccharomyces cerevisiae corresponding to samples from the Miocene and Oligocene. After comparison of the current genes with their ancient (up to 35-40 million years) counterparts it was concluded that essential genes such as rRNA18S are highly conserved and that even normal 'house-keeping' genes, such as PGU1, are strikingly conserved along the millions of years that S. cerevisiae has evolved.  (+info)

Cellular fine structures and histochemical reactions in the tissue of a cypress twig preserved in Baltic amber. (5/41)

A twig of a cypress plant preserved for ca. 45 Myr in Baltic amber was analysed by light and electron microscopy. Cross-sections of the whole plant showed an almost intact tissue of the entire stem and leaves, revealing, to our knowledge, the oldest and most highly preserved tissue from an amber inclusion reported so far. The preparations are based on a new technique of internal imbedding, whereby the hollow spaces within the inclusion are filled with synthetic resin which stabilizes the cellular structures during the sectioning procedure. Cytological stains applied to the sections reacted with cell walls and nuclei. A strong green auto-fluorescence of the cuticle and the resin canals in the leaves was observed. Transmission electron micrographs revealed highly preserved fine structures of cell walls, membranes and organelles. The results were compared with taxonomically related recent Glyptostrobus and Juniperus plants.  (+info)

First identifiable Mesozoic harvestman (Opiliones: Dyspnoi) from Cretaceous Burmese amber. (6/41)

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.  (+info)

Early Cretaceous spider web with its prey. (7/41)

The orb web is a spectacular evolutionary innovation that enables spiders to catch flying prey. This elegant, geometric structure is woven with silk fibers that are renowned for their superior mechanical properties. We used silk gland expression libraries to address a long-standing controversy concerning the evolution of the orb-web architecture. Contrary to the view that the orb-web design evolved multiple times, we found that the distribution and phylogeny of silk proteins support a single, ancient origin of the orb web at least 136 million years ago. Furthermore, we substantially expanded the repository of silk sequences that can be used for the synthesis of high-performance biomaterials.  (+info)

Amber from western Amazonia reveals Neotropical diversity during the middle Miocene. (8/41)

Tertiary insects and arachnids have been virtually unknown from the vast western Amazonian basin. We report here the discovery of amber from this region containing a diverse fossil arthropod fauna (13 hexapod families and 3 arachnid species) and abundant microfossil inclusions (pollen, spores, algae, and cyanophyceae). This unique fossil assemblage, recovered from middle Miocene deposits of northeastern Peru, greatly increases the known diversity of Cenozoic tropical-equatorial arthropods and microorganisms and provides insights into the biogeography and evolutionary history of modern Neotropical biota. It also strengthens evidence for the presence of more modern, high-diversity tropical rainforest ecosystems during the middle Miocene in western Amazonia.  (+info)