The Ants of the Genus Lasius (Hymenoptera, Formicidae) from Late Eocene European Ambers

Finds of the genus Lasius Fabricius in the Baltic, Bitterfeldian, Rovno, and Scandinavian Ambers (Late Eocene) are revised. Neotypes of L. pumilus Mayr, 1868 and L. punctulatus Mayr, 1868 are designated. A key to workers and gynes of Lasius species from the Late Eocene European ambers is compiled. All Lasius species from these ambers belong to the subgenus Lasius s. str. L. schiefferdeckeri Mayr, 1868 is one of most abundant ant species in the Late Eocene European ambers: it consists 15.2—19.5% of all ant specimens in Baltic Amber, 24.5% in Bitterfeldian Amber, 23.8% in Rovno Amber, and 23.6% in Scandinavian Amber of the examined collections. Based on the features of fossilization of this species, it is possible to assume that at least in part it constructed arboreal nests and made roads to aphids’ colonies. The list of nine ant species found in syninclusions with L. schiefferdeckeri is provided.Ревизованы находки рода Lasius Fabricius из балтийского, биттерфельдского, ровенского и скандинавского янтарей (поздний эоцен). Обозначены неотипы L. pumilus Mayr, 1868 и L. punctulatus Mayr, 1868. Приведена таблица для определения видов Lasius позднеэоценовых янтарей Европы по рабочим и самкам. Все виды из позднеэоценовых янтарей Европы относятся к подроду Lasius s. str. Одним из самых массовых видов муравьев янтарей является L. schiefferdeckeri Mayr, 1868. В изученных репрезентативных коллекциях балтийского янтаря его особи составляли 15,2—19,5%, биттерфельдского – 24,5%, ровенского – 23,8% и скандинавского – 23,6%. Основываясь на особенностях захоронения этого вида, можно предполагать, что его гнезда, по крайней мере, частично располагались на деревьях и что муравьи делали на стволах дороги к колониям тлей. Приведен список из 9 видов муравьев, обнаруженных в сининклюзах с L. schiefferdeckeri

The wasps, bees and ants (Insecta: Vespida=Hymenoptera) from the Insect Limestone (Late Eocene) of the Isle of Wight, UK

The types and undescribed material of the hymenopteran fossils of the Insect Bed of the Bembridge Marls from the Isle of Wight (UK) are critically revised and studied. A total of 1460 fossils are recorded and attributed to 20 families: Gasteruptiidae s.l. (1); Proctotrupidae (3); Diapriidae (24); Cynipidae (7); Figitidae (6); Pteromalidae (1); Agaonidae (3); Scelionidae (12); Platygastridae (2); Ichneumonidae (32); Braconidae (75); Bethylidae (3); Crabronidae (2); Sphecidae (1); Apidae (2); Scoliidae (1); Tiphiidae (2); Vespidae (4); and Formicidae (1220). Described as new are 51 species, 13 genera, two tribes and two subfamilies. Minimum number of species recorded (either as described species or representing higher taxa with no described species in the assemblage) is 118. The composition of the hymenopteran assemblage is most similar to that of Baltic amber and indicative of a well forested territory, as well as of a humid, equable (aseasonal but not very hot) climate, more typically equable than in the Baltic amber source area, judging from the absence of Aphidiinae and scarcity of aphids

Ant mound as an optimal shape in constructal design: Solar irradiation and circadian brood/fungi-warming sorties

Sizes, shapes, ambient and in-dome temperature, incoming solar radiation and illumination are measured on a Formica rufa anthill in a mixed forest of the Volga-Kama National Reserve in Russia. These data are used in a conceptual model of insolation of a right conical surface by direct-beam, descending atmospheric and ascending ground-reflected radiation. Unlike a standard calculation of the energy flux intercepted by a solar panel, the anthill is a 3-D structure and double-integration of the cosine of the angle between the solar beams and normal to the surface is carried out for a "cozy trapezium", where the insects expose themselves and the brood to "morning" sunbathing pulses ( Jones and Oldroyd, 2007). Several constructal design problems are formulated with the criteria involving either a pure solar energy gained by the dome or this energy, as a mathematical criterion, penalized by additive terms of mechanical energy (potential and friction) lost by the ants in their diurnal forays from a "heartland" of the nest to the sun-basking zone on the surface. The unique and global optima are analytically found, with the optimal tilt angle of the cone explicitly expressed through the zenith angle of the Sun and meteorological constants for the isotropic sky model. © 2014 Elsevier Ltd

The ants of the genus Myrmica (Hymenoptera, Formicidae) from Baltic and Saxonian amber (Late Eocene)

Seventeen extinct ant species have been ascribed to the genus Myrmica: four species from the Late Eocene and Oligocene (ca. 40–35 Ma) and thirteen from the Miocene (ca. 25 Ma). However, only one of these species, M. longispinosa Mayr, found in Baltic Amber, indisputably belongs to the genus. All other fossil ‘‘Myrmica’’ species belong to other genera. The extinct genus Nothomyrmica is considered to be heterogenic, artificially joining unrelated species (including some Myrmica) having the common feature of the absence of spurs on the hind and middle tibia, therefore N. intermedia and N. rudis are transferred to the genus Myrmica. Also, two new Myrmica species from European amber are described, a key for the identification of the extinct Myrmica species indisputably belonging to the genus, is provided and the possible paths of Myrmica evolution are discussed

Two new primitive ant genera from the late Eocene European ambers

Two extinct genera of ants from the late Eocene (ca. 40 Ma), Protomyrmica gen. nov. and Plesiomyrmex gen. nov. (family Formicidae, subfamily Myrmicinae), are described based on single specimens (males), from Baltic and Bitterfeld (also called Saxonian) ambers respectively; both genera belong to the tribe Myrmicini. In gross morphology they are similar to modern Myrmica but have a series of apomorphies combined with characters that are plesiomorphic not only in the tribe Myrmicini, but also in the subfamily Myrmicinae. The most significant plesiomorphies concern the antennal structure and wing venation of both genera. The antennal scape is short and the funiculus is filiform, having no apical club. Moreover, the antennae of Protomyrmica are “sphecoid” with the length of the funicular segments gradually decreasing towards the apex (i.e., the longest is basal, starting from the second, and the shortest is apical); this type of structure is basal for the family Formicidae as a whole. Although we consider the wing venation of Protomyrmica to represent the prototype of wings in the subfamily Myrmicinae, it has an apomorphy absent in the modern Myrmicini genera—the antennae are inserted into the head well behind the posterior margin of the clypeus. Plesiomyrmex also has a peculiar apomorphy not found in any other genus of Myrmicinae: the antennae are inserted into toruli located on short sub−vertical tube−like or cup−like structures that protrude distinctly above the head surface. As a result, we do not consider either of the newly described genera to be the direct ancestors of modern Myrmicini; nevertheless, the presence of very ancient plesiomorphies may indicate their antiquity, and thus the latest estimated time for the origin of the tribe Myrmicini should be at least the early Eocene