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A new species of silvanid flat bark beetle, Protoliota paleus sp. nov., is described from mid-Cretaceous Burmese amber. Protoliota paleus nov. sp. differs from a previous member of the genus described in Burmese amber by its small body size, weakly protruding eyes, long mandibles, and narrow pronotum. The new fossil is characterized by extremely elongate antennae and setiferous pads on its fore tarsus. Discussion is presented on the purpose of both of these attributes and how they could play a role in the survival of the species. A list of the superfamily Cucujoidea described from Burmese amber is included.

Premise of research. This investigation was undertaken to describe a multifloral grass spikelet enclosed in Baltic amber. The fossil, described in the new genus Eograminis, represents the first def...

Tropidogyne euthystyla, described here, is the fourth species of this fossil genus to have been reported from amber deposits in northern Myanmar. The species are alike in features of the calyx, the shape and venation of the inferior ovary, and the absence of petals. They differ in the number and form of the styles, the lobing of the epigynous disc, and whether the flowers are apparently bisexual or unisexual. In the one species for which several flowers are available for study, T. pentaptera, floral diameters vary from 3.5 to 5.0 mm. The present species, known only from a single flower, is the smallest in the genus, with a floral diameter of only 2 mm. It differs from the 3 previously described species in having 2 stout, erect styles bearing a terminal stigma, whereas the other species have 2 or 3 short or long, arching styles that are decurrently stigmatic along the adaxial surface.

Although partially damaged prior to its preservation in coniferous resin, the flower of Cyathitepala papillosa retains enough morphological features to justify its description as a new genus and species of fossil angiosperms. The perianth is incomplete, but there are at least 6 large outer tepals and numerous smaller, spirally arranged inner ones. The limbs of some of the larger tepals are cup-shaped and face abaxially, while the smaller inner tepals are flat or have adaxially folded margins. There is an inner series of erect, apically truncate tepals surrounding the stamens. The surfaces and margins of the tepals are densely papillate. There is a whorl of ca. 12 stamens with anthers that dehisce by two dorsally hinged valves. Nothing remains of the receptacle or pedicel of the flower, but the superior portion of the pistil is conic and bears two columnar, erect styles. The fossil is compared with three previously described fossil genera, Setitheca, Zygadelphus, and Strombothelya, which were suggested as having a possible relationship with certain families of order Laurales.

A flower preserved in 100 Ma amber from Myanmar is described here as Chainandra zeugostylus, a new genus and species of fossil angiosperms. The anthers in Chainandra are sagittate at the base and have only a short connective. They dehisce by means of a circumferential stomium, the dorsal and ventral sides of each locule forming flaps that become widely separated. The style of Chainandra is columnar and two-branched above the middle, and the fully inferior ovary bears an epigynous nectar disc but lacks well-defined ribs or veins. In Tropidogyne, Lacknociona, and Strombothelya, similar genera described earlier from the same am-ber deposits, the styles are either unbranched or are 3–5-branched to near the base, and the ovary is half-inferior to inferior, its lower portion often being dis-tinctly veined and ribbed. Morphology of the stamens and gynoecium of the three genera suggests that they are early members of the eudotyledons.

The flower described here as Valviloculus pleristaminis, a new genus and species of fossil angiosperms, was obtained from Myanmar amber deposits dating to the mid-Cretaceous period. The flower is staminate, with an ovoid, hollow floral cup. The perianth consists of 6 tepals, one of which was lost prior to preservation. Numerous helically arranged stamens are borne at the summit of the flower. The anthers are bilocular, with pollen sacs that dehisce by laterally hinged valves. The tip of the connective bears a cup-shaped appendage. The gynoecium is represented only by a cluster of vestigial styles centered among the stamens. The fossil is provisionally assigned to order Laurales, its closest affinities being with the families Monimiaceae and Atherospermataceae.

A fossil flower in mid-Cretaceous amber from Myanmar (Burma) is described as the new genus and species Phantophlebia dicycla. The perianth of the flower is composed of two 5-merous whorls of tepals, the outer tepals being smaller and more irregular in shape than the inner. All the tepals are distinctly vascularized, with few to many major veins that are connected above by an irregular network of veinlets. The flower’s 5 stamens are opposite the inner tepals, with bilocular anthers that dehisce by latrorse, oblique slits. No gynoecium can be seen beneath the air bubble covering the center of the flower. The fossil shares some characteristics with myrsinoid members of family Primulaceae.

The fossil flower described here as Thymolepis toxandra is from amber deposits in Myanmar which have been dated as ca. 100 Ma. The peri-anth consists of 12 tepals of varying size and shape, arranged in decussate pairs at the summit of an obconic floral cup. The epidermis of some of the tepals is densely papillate-secretory. The flower is bisexual, the androecium consisting of 2 stamens whose anthers are bisporangiate, hippocrepiform, and densely hirsute. The gynoecium is visible only as a bilobed stigma or as the tips of two postgenitally fused styles, the re-mainder of the pistil(s) being hidden by the perianth and floral cup. It is suggested that the fossil may be an early representative of family Monimiaceae.

A new fossil angiosperm, Dasykothon leptomiscus, is described from mid-Cretaceous amber deposits in the Hukawng Valley of northwestern Myanmar (Burma). The flower is post-anthesis except for one stamen that retains its pollen. The perianth is slightly irregular and composed of 5 ovate or lance-linear, erect or incurved sepals. The ca. 12 stamens have slender, elongate filaments and dorsifixed, bithecal, longitudinally dehiscent anthers. The superior ovary bears 2 long, curved styles. Germinating pollen grains observed on the stigmas are monoporate and have the peculiar feature of a grooved ridge encircling the grain from pole to pole. This structure is hypothesized to be an evolutionary elaboration of the meridionally syncolpate sulcus found in some members of the Atherospermataceae. The generalized floral morphology of the fossil prevents ready taxonomic assignment to a modern family.

Summary A new species of fossil mermithid, Heydenius simulphilus sp. n. (Nematoda: Mermithidae), is described from two parasitic juvenile specimens adjacent to a male black fly (Diptera: Simuliidae) in Baltic amber. It is proposed that the nematodes emerged from their developmental sites in the haemocoel of the black fly host through a wound in the abdomen of the latter, as indicated by the release of a droplet of haemolymph and damaged cuticle. Various internal structures of the nematodes are identified and related to those found on extant developing mermithids. This is the first fossil record of mermithid parasitism of a black fly.

A new genus and species of froghopper, Araeoanasillus leptosomus gen. et sp. nov. (Hemiptera: Cercopoidea, Sinoalidae?), is described from mid-Cretaceous Burmese amber. The new genus possesses the following diagnostic characteristics: slender, medium size body (length, 7.0 mm) with head longer than wide, round eyes; antennae slender with eight antennomeres; pedicel very short, shorter than scape; pronotum with a length/width ratio of 2.4; metatibia with three spines, including one short spine near base and two adjacent, long, thick spines near apex; a single series of 16 thick apical teeth (comb) at metatibial apex; tegmen narrow with a length/width ratio of 3.2; tegmen with coastal area and stigmal cell punctate; CuP meeting base of CuA2; and MP branching at middle of wing. In hind wing, Cu vein forked once. A series of plant trichomes adjacent and attached to the specimen suggests that the froghopper’s host plant was a fern.

A tylenchid nematode parasite of a male long-legged fly, Tachytrechus sanus Osten Sacken (Diptera: Dolichopodidae) from Montana, USA is described as Parasitylenchus myiophagus n. sp. (Nematoda: Parasitylenchidae). The new species is characterized by the presence of an extremely long first generation female and numerous short and wide second generation males and females produced in “enclosed” clusters in the host’s body cavity. Both generation female nematodes are ovoviviparous, with short stylets lacking knobs and simple tails lacking spikes, palps or mucrons. The second generation males have paired, separate spicules, short stylets, and a bursa but no visible gubernaculum. The fly host shows evidence of demasculinization, which is attributed to nematode parasitism. The gonads of the second generation adults are infected with a microsporidium (Microsporidia), which is a new host record for tylenchid nematodes. A tylenchid-infected Baltic amber dolichopodid shows that associations between these two organisms extend back at least to the Eocene.

The subterranean termite Reticulitermes flavipes (Kollar, 1837) (Isoptera: Rhinotermitidae) occurs throughout the eastern USA and populations have been found as far west as Oregon. As with other termites, eastern subterranean termites live in colonies composed of workers, soldiers and reproductives. The blind, wingless workers, which are only between 3 and 4 mm long, feed on wood and can cause serious damage to wooden structures throughout their range (Edwards & Mill, 1986). Mermithid parasitism of termites is a rare occurrence and this report represents the first case of mermithid parasitism of termites in North and Central America.

The flower described here as Zygadelphus aetheus gen. et sp. nov. was obtained from amber mines in Myanmar, preserved in marine sedimentary deposits dating to the mid-Cretaceous Period, ca. 99 My in age. The perianth consists of ca. 10 spirally arranged tepals that vary in size and shape. The stigmatic tips of two styles are visible, the remainder of the gynoecium being hidden from view by the crowding of stamens and perianth parts toward the center of the flower. There is a whorl of 4 stamens, the anthers of which have the feature, probably unique among angiosperms, of possessing a small but complete accessory stamen arising as an appendage on their dorsal surface. Anthers of both types of stamens are bilocular and dehisce by dorsally hinged valves. Presence of pollen in the accessory anthers indicates that they functioned in reproduction. Under the assumption that the fossil is not merely a teratological mutant in an otherwise normal-flowered species, it is here given taxonomic status as representing a peculiar type of floral development, now extinct, that existed during an earlier stage of angiosperm evolution.

The fossil flower described here is the third species of Tropidogyne to have been collected from mid-Cretaceous amber deposits in the Hukawng Valley of northwestern Myanmar. The flower of Tropidogyne lobodisca differs from the 2 previously described species, T. pikei and T. pentaptera, in lacking stamens and having a 5-lobed nectar disc covering the apex of the ovary. Its 2 slender, curved, attenuate styles are like those of T. pentaptera in being stigmatic along the adaxial surface. The new species has 5 spreading, reticulately-veined sepals, a generic character of Tropidogyne. An unusual, probably teratological, feature is the presence of 2 sepal-like staminodes on one side of the flower, inserted at the base of the nectar disc where stamens would otherwise be found. The inferior portion of the pistil is obconic, with 5 distinct veins that connect to the mid-nerves of the sepals.

Strombothelya, a new genus of fossil angiosperms from Myanmar amber deposits, is represented by 2 flowers that are here described as separate species. Flowers of Strombothelya have 5 spreading, more or less distinctly veined sepals. Petals are absent. There are 10 inwardly arching stamens and a half-inferior ovary, whose broadly conic superior portion terminates in 1 or 3 stout, columnar, apically truncate styles. The superior portion has a papillate surface that was probably nectarifer-ous. The inferior portion of the ovary in both species is obconic and 5- or 10-ribbed. The fossils are comparable in certain respects to the genus Tropidogyne, described earlier from the same amber deposits. The 3 species of Tropidogyne have flowers with 5 or 10 stamens and 2 or 3 slender, curved, acutely-tipped styles. The inferior portion of the ovary is strongly 10-ribbed, while the superior portion is flat or cushion-shaped and bears a lobed nectar-disc. Strombothelya and Tropidogyne inhabited a Cretaceous araucarian rainforest, which may have been located in the Southern Hemisphere continent of Gondwana.

Three flowers of a fossil angiosperm preserved in amber from Myanmar (Burma) are described as the new genus and species Dispariflora robertae. Although joined in a single cymose inflorescence, the flowers are variable in size and, in addition, they possess an unusual perianth in which 1 sepal is much enlarged and leaf-like, while the remaining 4 are smaller and unequal. The flowers each have 1 superior pistil with a peculiarly plumose and bristly ovary. The number of stamens is uncertain because most were lost before floral preservation, but scars on the receptacle suggest that at least 15 were present. The bithecal anthers open by longitudinal slits and basal glands may have been present on the filaments. Taken as a whole, the floral features that characterize Dispariflora suggest an affinity with members of Laurales, especially several Southern Hemisphere families allied with the Monimiaceae.

The knobbed setae on a small caterpillar in 45-55 million years old [Eocene] Baltic amber were studied and characterized as urticating, with evidence of liquid release implying the production of poisons. It is presumed that the caterpillar had been disturbed just prior to falling into the resin, as some of its setae showed defensive responses. The swollen tips of the setae are equipped with "trip hairs" and when disturbed, the tips release liquid deposits, some of which contain rod-like bodies. These setal responses to a disturbance are the first report of poisonous setal defense mechanisms in a fossil insect.

Priscadvena corymbosa gen. et sp. nov., is described from thalli and sporangia emerging from the oral cavity of a click beetle (Coleoptera: Elateridae) in mid-Cretaceous Burmese amber. The fossil contains several features unknown in extant Trichomycetes including a click beetle (Coleoptera: Elateridae) host, spiny, aerial thalli with the entire thallus bearing numerous small uninucleate globular spores and stalks attached to the oral cavity of its host. Based on these features, P. corymbosa gen. et sp. nov. is placed in a new family, Priscadvenaceae fam. nov., and new order, Priscadvenales ord. nov. The new morphological and behavioral features of the fossil add to the diversity of the trichomycetes as currently defined.

An ancient fungal parasite of a Camponotus ant (Formicidae: Hymenoptera) in Baltic amber is described as Allocordyceps baltica gen. et sp. nov. (Hypocreales: Clavicipitaceae). The new genus is characterized by an orange, stalked, cup-shaped ascoma with partially immersed perithecia that emerges from the rectum of the ant, two separate stromata with septate mycelium that emerge from the base of the neck and the abdomen of the ant, respectively, and free-standing putative perithecia bearing putative asci with putative multicellular ascospores fragmented into one-celled partspores. This oldest known fossil fungus of an ant could represent a precursor of the genus Ophiocordyceps, which at present is the only fungal lineage parasitizing ants of the genus Camponotus. The fossil shows unique morphological features that existed in the Hypocreales some 35–55 MYA.

A new genus and species of scale insect (Hemiptera: Coccomorpha) is described from a female specimen in mid-Cretaceous Burmese (Myanmar) amber. Fossil female scales are rare and the present species, described as Paleolepidotus macrocolus gen. et sp. n., has such an unusual assortment of morphological features that it could not be assigned to any particular extant or extinct family. The small, ferruginous specimen exhibits a series of long wax pencils that extend around the body, including the head. The antennae and legs are quite long compared to other extant and extinct scale fossils. Of special interest are the protruding eyes, and a conical-triangular rostrum arising from between the forelegs; the claws with bifid apices are also unique. The ovisac contains immature stages.

A single staminate flower preserved in mid-Cretaceous Myanmar amber is described as Setitheca lativalva gen. et sp. nov. The fossil’s affinities appear to be with Monimiaceae and allied families of order Laurales. The perianth is composed of ca. 12 spirally arranged tepals of varying size and shape. A single whorl of 10 stamens is attached to the margin of a flat central disc. There is no gynoecium. In some of the stamens, the bilocular anthers are held upright, but in the others, the filaments are arched abaxially and the anthers are reflexed. Dehiscence is extrorse via 2 lateral, dorsally-hinged valves, as also occurs in some members of Hernandiaceae. The spherical pollen appears to be inaperturate. Such features as the unisexual flowers, valvate anthers, and a perianth of numerous, spirally arranged tepals are consistent with assignment of the fossil to this order of angiosperms.

Endobeuthos paleosum gen. et sp. nov. is based on 6 flowers preserved together in a single block of mid-Cretaceous amber from Myanmar (Burma). The calyx is composed of ca. 50+ small, helically arranged sepals. The corolla consists of 5 imbricate petals forming a sheath-like structure that is usually concealed within the calyx. The petal tips are often spreading and exserted from the calyx. There are numerous stamens, each of which consists of a filament and an enlarged anther connective with a single lateral, bisporangiate theca. Dehiscence is extrorse. The tips of 3 or 4 styles are visible, indicating that the flowers are bisexual. The fossils possess unique features that prevent assignment to any modern family. However, the numerous sepals and stamens and a thickened anther connective may suggest an association of E. paleosum with the family Dilleniaceae.

A new species of fossil mermithid,Cretacimermis aphidophilussp. n. (Nematoda: Mermithidae), is described from the primitive extinct aphid,Caulinus burmitis(Hemiptera: Burmitaphididae), in mid-Cretaceous Myanmar amber. Aphid parasitism by mermithid nematodes is rare today with only two known cases involving root-feeding aphids. Based on the habits of the parasitised extant aphid hosts, it is likely that the fossil aphid was also a root parasite and encountered the infective stage mermithid in the soil. Such fossils provide rare glimpses of nematode-host associations from the distant past and provide minimum dates for the appearance of specific mermithid clades.

We report the second record of a grammitid fern from Dominican amber. The fossil comprises a single fertile pinna with excellent preservation, thus allowing a clear view of unaltered morphological characters. Venation, indument, and sori match the protologue of the previously described species from Dominican amber, Grammitis succinea L. D. Gomez, so we assign our fossil to that species. Characters of both specimens of G. succinea are sufficient to place it within the grammitid clade of the Polypodiaceae. However, it does not agree with Grammitis as it is currently circumscribed. We explore possible relationships between the fossil and other extant grammitid genera through Principal Coordinates Ordination (PCOa) of 109 morphological characters and through phylogenetic analysis of combined morphological and plastid DNA sequence data. Character combinations found in the fossil are inconsistent with those of any extant genus and our PCOa analysis did not suggest a clear affinity with any extant genus. This uncertainty is reflected in the results of our phylogenetic analyses, which find multiple most-parsimonious positions for the fossil within the grammitid clade. Based on these results, we suggest that the fossil belongs to an early divergent lineage of grammitid ferns, and cannot be assigned to any extant genus. Consequently, we place both specimens in a newly described fossil genus, Polymniopteris, and make a new combination for G. succinea within it. Because the type of G. succinea cannot be located, we designate the present specimen a neotype.

A densely scaled small mushroom in Baltic amber is described as Gerontomyces lepidotus gen. et sp. nov. and is characterized by a convex pileus 1.0 mm in diameter, distant to subdistant lamellae with smooth margins and a centrally inserted cylindrical, solid stipe. Its taxonomic placement is uncertain. This is the first mushroom described from Baltic amber.

The first fossil flowers of Neotropical Urticaceae (Boehmerieae) are described from the Dominican Republic and Mexico as belonging to a new genus, Ekrixanthera. Ekrixanthera hispaniolae sp. nov. from Dominican amber has pentamerous staminate flowers on short pedicels with a pilose pistillode and heteromorphic pilose tepals: two are clavate and three linear. Ekrixanthera ehecatli sp. nov. has pentamerous staminate flowers lacking pedicels, a pistillode with greatly reduced pilosity, glabrous and heteromorphic tepals with two linear and three wedge-shaped with truncate tips. The presence or absence of a pedicel, heterotrophic condition of the tepals, and the presence or absence of pilosity of the pistillode and tepals separate the two species. Those characters, together with the pentamerous flowers separate both fossil species from extant genera. The floral structures indicate explosive pollen release and pollination by wind (anemophily). Pistillate flowers have not been found for this usually dioecious tribe. Lepidopteran herbivory is suggested by a damaged stipule in one specimen and a nymphalid butterfly (Vanessa-like) caterpillar that may have used Ekrixanthera as a food plant is illustrated. The fossils establish an early lineage of Boehmerieae with characteristic explosive pollen release and perhaps associated herbivorous insects in the West Indies and North America during the mid-Tertiary.

An ambrosia fungus is described from filamentous sporodochia adjacent to a wood–boring ambrosia beetle (Coleoptera: Curculionidae: Platypodinae) in mid-Cretaceous Burmese amber. Yeast-like propagules and hyphal fragments of Paleoambrosia entomophila gen. nov. et sp. nov. occur in glandular sac mycangia located inside the femur of the beetle. This is the first record of a fossil ambrosia fungus, showing that symbiotic associations between wood–boring insects and ectosymbiotic fungi date back some 100 million years ago. The present finding moves the origin of fungus-growing by insects from the Oligocene to the mid-Cretaceous and suggests a Gondwanan origin.

Examination of a small portion of the viscera of an oarfish (Regalecus russellii) recovered from Santa Catalina Island, southern California, revealed numerous tetraphyllidean tapeworm plerocercoids, Clistobothrium cf. montaukensis; 2 juvenile nematodes, Contracaecum sp.; and a fragment of an adult acanthocephalan, family Arhythmacanthidae. This suggests that the fish was relatively heavily parasitized. The presence of larval and juvenile worms suggests that oarfish are preyed upon by deep-swimming predators such as the shortfin mako shark, Isurus oxyrinchus, known to be a definitive host for the adult tapeworm, and also by diving mammals such as sperm whales, Physeter catodon L., hosts of Contracaecum spp. nematodes.

SummaryNew species of rhynchitid weevils, Rhynchitobius tanyrhinus n. sp. and R. xuthocolus n. sp. (Coleoptera: Rhynchitidae) in the tribe Auletini are described from Dominican amber. The former species is characterized by a long rostrum, narrow pronotum and elytra, rugose elytral intervals and distinct elytral striae. The latter species has a short rostrum, wide antennal club, yellow legs, non-rugose elytral intervals and weak elytral striae. The present study describes the first representatives of the family Rhynchitidae from Dominican amber.

Our study of the Hat Creek amber (Poinar et al. 1999) was undertaken to determine the range of the biota in the resin, to identify the plant that produced the resin, and to assess the future implications of these significant deposits. The study was in no way “compromised” by providing an alternative interpretation of the systematic position of the genus Sphecomyrma Wilson and Brown.

SummaryNew genera and species of jumping ground bugs (Hemiptera: Schizopteridae) are described in Dominican and Burmese amber. In Dominican amber are described: Hypselosoma dominicana Poinar & Brown sp. n., Schizoptera dominicana Poinar sp. n. and Schizoptera hispaniolae Poinar sp. n. In Burmese amber are described: Lumatibialis burmitis Poinar gen. et sp. n. and Hexaphlebia burmanica Poinar gen. et sp. n. A triungulin attached to the dorsum of the abdomen of Lumatibialis burmitis is described as Microentomus epibatus Poinar gen. et sp. n. in the family Meloidae (Coleoptera). This specimen represents the oldest known triungulin and the first fossil phoretic association of a triungulin and hemipteran.

The Myristicaceae is a member of the early diverging angiosperm order Magnoliales; however, the family is poorly represented by fossil collections. We describe Virola dominicana sp. nov. (Myristicaceae), the first record of fossilized Myristicaceae flowers, from mid-Tertiary (45–15 million years ago) Dominican amber. The description is based on 24 male flowers in 17 pieces of amber, thus providing some indication of intraspecific variation, including a two-tepaled flower. Diagnostic characters of the new species are the long-simple or few-branched trichomes on the perianth margins, the small pollen grains, and a short staminal column. These fossils also show co-occurring insects, some of which could be Virola pollinators. It is speculated that V. dominicana disappeared from Hispaniola during the Pliocene–Pleistocene cooling events leaving no native members of the Myristicaceae in this region today. Additionally, these fossils demonstrate that Myristicaceae was present in the Western Hemisphere during the mid-Tertiary.

Hastisetae are extremely elaborate and intricate insect setae that occur solely on dermestid larvae (Coleoptera: Dermestidae). The present work characterizes hastisetae found in mid-Cretaceous amber from Myanmar and compares them to hastisetae found on extant dermestid larvae. The presence of hastisetae in Myanmar amber shows that lineages of dermestid beetles had already developed hastisetae by the mid-Cretaceous and their presence allows us to follow the evolutionary development of this particular arthropod structure over the past 100 million years. Hastisetae attached to a parasitic wasp in the same piece of amber indicates that ancient dermestid beetles used their hastisetae for defense, similar to their function today.

A mid-Cretaceous Eccrinales in Myanmar amber is described as Paleocadus burmiticus gen. et sp. nov. in the family Eccrinaceae. The fossil is represented by two types of sporangiospores formed on different thalli protruding from the anus of a primitive wasp, with secondary infestation spores multinucleate and thin walled. Its presence establishes the Eccrinales in the mid-Cretaceous and shows that at that time, lineages of this group parasitized wasps, an association unknown with extant members of the Order.

Eight new species of short-palped crane flies (Diptera, Limoniidae) are described from Mexican amber: Dicranomyia (Caenolimonia) alexbrowni Podenas and Poinar,Dicranomyia (Dicranomyia) chiapa Podenas and Poinar, Dicranomyia (Dicranomyia) mexa Podenas and Poinar, Dicranomyia (Dicranomyia) vella Podenas and Poinar, Erioptera (?Mesocyphona) beata Podenas and Poinar, Erioptera (Mesocyphona) diver Podenas and Poinar, Erioptera (?Mesocyphona) sherry Podenas and Poinar and Helius (Helius) collemus Podenas and Poinar. Additionally, two Limoniidae species belonging to undescribed species of the genus Dicranomyia Stephens, 1829 from Mexican amber are characterized. The key for Dicranomyia from Dominican and Mexican amber is added.

Four new species of fossil mermithids (Nematoda: Mermithidae) are described from amber: Heydenius arachnius n. sp. from a spider (Arachnida: Araneae) in Dominican amber, H. phasmatophilus n. sp., from a walking stick (Phasmatodea: Phasmatidae) in Baltic amber, H. podenasae n. sp. from a moth (Lepidoptera) in Baltic amber and H. trichorosus n. sp. from a caddis fly (Trichoptera: Leptoceridae) in Baltic amber. With previous descriptions of fossil mermithids from Diptera, Coleoptera, Hymenoptera and Hemiptera, there are now representatives of seven insect orders as hosts of fossil mermithids. With these additional four fossils, the total number of described nematode fossils is now 95, with 70 occurring in amber.

Morphological and molecular studies were used to determine the systematic affinity of the sea urchin parasite, Echinomermella matsi. The absence of somatic ornamentation and external openings in the parasitic juveniles and adults, aside from a small non-functional mouth and male reproductive opening, shows a striking degree of morphological reduction in Echinomermella as an adaptation to a parasitic life style. A phylogenetic analysis of E. matsi by the maximum likelihood (ML) and neighbour-joining (NJ) methods places it within the Order Enoplida. This indicates that Echinomermella evolved from free-living marine enoplids and is not closely related to the Mermithidae as previously thought. The absence of a vulva and male genital supplements, coupled with the modified spicule tips, suggest that traumatic insemination is the standard method of mating. The morphological modifications in Echinomermella indicate a long period of co-evolution with sea urchins, possibly extending back to the Palaeozoic.

†Tropidogyne pikei K. L. Chambers, Poinar & R. T. Buckley, representing a new genus and species, is described from an Early Cretaceous flower preserved in Burmese amber. †Tropidogyne may occupy a stem or early crown position in the phylogeny of the rosid clade. Its floral morphology, while largely plesiomorphic, can be compared with the modern family Cunoniaceae. The flower of the fossil taxon is small, bisexual, epigynous, apetalous, with five regular sepals slightly connate at the base, 10 stamens, the one preserved anther having two thecae that dehisce by longitudinal slits, an ovary of three carpels surmounted by a conspicuous disc, three short, acute styles, and a 10-ribbed inferior ovary. At the summit of each rib of the †Tropidogyne ovary is a small, darkly stained patch of tissue, interpreted here as a secretory gland.

Six new fossils of Micromalthus (Coleoptera: Archostemata) from Dominican amber are compared with extant and previously described fossil micromalthid beetles. The amber inclusions are well preserved and all important morphological features are visible. Taking into account the morphological variability of the extant species Micromalthus debilisLeConte, 1878, it is not possible to find any morphological features that distinguish the fossils from the extant species. This also applies to the Dominican amber inclusion described as Micromalthus anasi Perkovsky, 2008, which therefore is considered a junior synonym of M. debilis. The lack of morphological change in M. debilis over time might possibly be explained by unusually stable environmental conditions, as this species occupies a very specialized ecological niche in decaying timber. A general survey of fossil insects indistinguishable from extant species is presented. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158, 300–311.

Two new genera, Burmoptera and Drinosa, one new subgenus, Limnophila (Burmolimnophila), and seven new species, Burmoptera azu, Drinosa prisca, Austrolimnophila (Austrolimnophila) joana, Lebania scomax, Limnophila (Burmolimnophila) bora, ?Antocha (?subgen.) lapra and Trentepohlia (Paramongoma) dzeura (Diptera, Limoniidae), are described from Burmese amber. Fragments of two species belonging to the genera Gonomyia (Gonomyia) and Helius are also characterized.

A new species of blister beetle, Meloe (Meloe) dominicanus (Coleoptera: Meloidae), is described from a triungulin in Dominican amber. The new species is characterized by its small size (under 1 mm), large, laterally positioned eyes and antennal structure. The specimen is attached to a hair on the occiput of a worker stingless bee, Proplebia dominicana Wille and Chandler, 1964 (Hymenoptera: Apidae). This is the first official description of a meloid in any amber deposit, the first New World record of a fossil meloid triungulin and the first record of a meloid triungulin associated with a stingless bee.

Pantostictus burmanicus Poinar and Brown, a new genus and new species of hister beetles (Coleoptera: Hydrophiloidea: Histeridae) are described from Cretaceous Burmese amber. The new genus is characterized by the following: small size (under 2 mm), prognathous head; head, pronotum and elytra covered with deep punctures; a 9- segmented geniculate antenna terminated with a 1-segmented asymmetrical club; tarsal formula 5-5-5; pairs of spines on all tarsal segments, fused elytra covering most of the abdomen, and a postocciput bearing paired triangular-shaped sclerotized apophyses. This represents the first Cretaceous member of the family.

A new genus and species of weevils (Coleoptera: Curculionidae: Anchineus dolichobothris Poinar and Brown) are described from Cretaceous Burmese amber. The new genus is characterized by: a long, narrow rostrum in the upper position, geniculate antennae with a loosely compact club, antennal scrobes extending the length of the rostrum, a lobed fifth tarsal segment, small trochanters, a well developed unguitractor plate, divaricate, toothed, tarsal claws and unequal ventrites.