Euglossa obrima, a new species of orchid bee from Mesoamerica, with notes on the subgenus Dasystilbe Dressler (Hymenoptera, Apidae)

A new species of the orchid bee subgenus Dasystilbe Dressler (Euglossini: Euglossa Latreille) is described and figured from a series of males and females collected broadly in Mesoamerica. Euglossa (Dasystilbe) obrima, sp. n., is differentiated from the one known species of Dasystilbe, Euglossa (Dasystilbe) villosa Moure, which occurs only in Panamá and perhaps Costa Rica. The subgenus and its constituent species are diagnosed, and comments provided on Dasystilbe.     

Revision of the orchid bee subgenus Euglossella (Hymenoptera, Apidae), Part I, The decorata species group

Euglossella, one of the most distinctive subgenera of orchid bees of the genus Euglossa, is composed of two characteristic assemblages of species, one of them comprising bees bearing the strongly metallic integument trademark of the genus (viridis species group), and the other consisting of bees with a brown integument shaded with metallic iridescence (decorata species group). Here we provide the first of two parts of a revision of Euglossella, providing diagnostic definitions for the subgenus, the decorata species group, and all the species included therein. Six species are included in the decorata group, one new: Euglossa (Euglossella) aurantia, sp. n.; Euglossa (Euglossella) apiformis Schrottky, resurrected status; Euglossa (Euglossella) decorata Smith, revised status; Euglossa (Euglossella) singularis Mocsáry, revised status; Euglossa (Euglossella) cosmodora Hinojosa-Díaz and Engel; and Euglossa (Euglossella) perpulchra Moure and Schlindwein. Euglossa meliponoides Ducke and Euglossa urarina Hinojosa-Díaz and Engel are newly synonymized under Euglossa decorata, Euglossa decorata ruficauda Cockerell is synonymized under Euglossa singularis, and a neotype is designated for Euglossa apiformis.     

Generic relationships within the Euglossini (Hymenoptera: Apidae)

ABSTRACT. .The relationships among the euglossine genera are examined. These genera form two natural groups, Exaerete+Euglossa , and Eufriesea+(Eulaema+Aglae). Each genus is discussed separately giving generic synonymy, biological notes and a complete species list. In addition, a key to the genera is provided.     

Frugivory by a stingless bee (Hymenoptera: Apidae)

Frugivory is not frequent among bees. Although stingless bees visit aged fruits for pulp, the use of fresh fruits is recorded only for Trigona hypogea Silvestri, a species that does not visit flowers. Here we report the occurrence of frugivory in Trigona amazonensis (Ducke), a flower-visiting stingless bee.     

The identity of the Neotropical stingless bee Frieseomelitta meadewaldoi (Cockerell, 1915) (Hymenoptera, Apidae)

A new study of a surviving syntype of Trigona meadewaldoi Cockerell, 1915, was undertaken and several widely employed names for Neotropical stingless bees recognized as junior synonyms. A lectotype is designated for Trigona meadewaldoi and the following new synonymies established: Tetragona francoi Moure, 1946, and Trigona (Frieseomelitta) freiremaiai Moure, 1963. These nomenclatural matters are here settled and the species thoroughly characterized in advance of a forthcoming phylogenetic consideration of the genus Frieseomelitta von Ihering, 1912.     

Nesting biology and nest re-use ofEulaema nigrita (Hymenoptera: Apidae,Euglossini)

Summary The nesting behavior of the euglossine beeEulaema nigrita was observed in the laboratory after being transferred from three nests to observation boxes. Nests were re-used by successive generations with more than one female working in each re-use process. Associated females were always of the same generation. All females that shared a nest foraged for construction materials (mud, excrement and resin) and each constructed, provisioned and oviposited in her own cells. The number of cells constructed by each female ranged from one to 23. Females stayed in the nests for periods ranging from 15 to 59 days during the hot and wet season and from five to 78 days during the cool and dry season. The egg-to-adult period was related to climatic conditions, and in all re-use processes it was longer than the time of residence of the females in the nests. The meloid beetleMeloetyphlus attacephalus was the only nest parasite. Due to the attack method employed by this parasite, the presence of more than one female in the nest did not result in improved nest defense.     

The melectine bee genera Brachymelecta and Sinomelecta (Hymenoptera,Apidae)

The enigmatic, cleptoparasitic bee genera Brachymelecta Linsley and Sinomelecta Baker (Apinae: Melectini) are redescribed, each represented by a single species which has not been reencountered since capture of the type series ca. 1878 and 1900, respectively. Both genera are the only melectines to possess two submarginal cells in the forewing but are otherwise wholly dissimilar. Brachymelecta mucida (Cresson), a species known only from the male holotype collected in “Nevada”, is newly described and figured, including the first account of the hidden sterna and genitalia. Sinomelecta oreina Baker is similarly described and figured based on the holotype male and paratype female, apparently collected from the eastern Tibetan Plateau. Both genera are valid and from the available data do not appear to represent merely autapomorphic forms of Melecta Latreille. Indeed, the terminalia of Sinomelecta oreina are in some respects more similar to those of species of Thyreus Panzer.     

Forest fragments with larger core areas better sustain diverse orchid bee faunas (Hymenoptera: Apidae: Euglossina)

Male orchid bees were attracted to chemical baits and collected in nine Atlantic Forest fragments in southeastern Brazil. Fragments differed in size and shape. Three additional sites were also sampled in a nearby large fragment. Three hypothetical core areas of each fragment were measured as the total area minus an area of 50, 100, and 200-m-wide perimeter. Abundance and richness were not correlated with either fragment size or ratio area/perimeter, but were positively correlated with the size of core areas. These results suggest that orchid bee conservation requires the preservation of the fragments with the largest possible core areas. Neither size nor shape alone (area/perimeter ratio) seemed to be good indicators of the value of a given fragment for sustaining diverse and abundant faunas of orchid bees.     

Phylogeny of the orchid bees (Hymenoptera: Apinae: Euglossini): DNA and morphology yield equivalent patterns

Orchid bees (Euglossini) are spectacular long-tongued Neotropical bees important in the pollination of Neotropical long-corolla flowers, particularly some orchids. Besides remarkably long tongues, males in particular exhibit other flower-related adaptations, including setal brushes on the foretarsi used for rasping the petals of orchids while collecting aromatic compounds. These compounds are stored in large swollen tibiae and are thought to play an important role in courtship behavior. Euglossini are also unusual in lacking sociality; they are the only tribe among the corbiculate bees that are not eusocial, and two of the genera are cleptoparasitic. Each genus exhibits distinct behavioral traits including nest architecture and host-parasite interactions, yet their evolution is unknown. Despite previous phylogenetic studies of on morphological characters, the relationships among the five euglossine genera remain under debate. We investigate euglossine generic relationships using DNA sequence data from four genes and new morphological characters. The morphological and molecular data yield congruent evolutionary patterns, and combining the data gives a fully resolved and well supported phylogeny of Euglossini.     

Effects of fragments and landscape characteristics on the orchid bee richness (Apidae: Euglossini) in an urban matrix,southwestern Amazonia

Orchid bees are important pollinators in tropical forests. Although studies have already detected effects of habitat loss and forest fragmentation on bee assemblages, little is known about orchid bees in urban forest fragments. The aim of this study was to analyse the influence of forest fragments (size and edge index) and landscape features (forest cover area and built-up area around the forest fragments, connectivity and spatial distance from the urban center) on the abundance, richness and composition of orchid bees. Male bees were attracted by odoriferous baits and collected in ten forest fragments of different sizes. In total, we collected 3166 male bees belonging to 4 genera and 38 species. The increase of the built-up area and the reduction of the forest cover area around the forest fragments decreased the abundance and richness of bees. We recorded a smaller number of bees in areas closer to the urban center. We failed to find a significant relationship between abundance/richness of bees and forest fragment area, edge index, and connectivity. We observed that the faunistic dissimilarity was positively correlated with the geographic distance between forest fragments. The forest fragments that presented greater landscape dissimilarity also presented greater faunistic dissimilarity. Our results suggest that the matrix structure around the forest fragments is an important factor that influences the Euglossini bee assemblages inside these forest fragments. Based on our results, we believed that the conservation of fragments with a larger forest cover area and smaller built-up areas around them contribute to the maintenance of the diversity of orchid bees and their pollination services.     

A new species of the cleptoparasitic bee genus Thyreus from northern Yemen and southwestern Saudi Arabia (Hymenoptera,Apidae)

A new species of cleptoparasitic bee of the genus Thyreus Panzer (Apinae: Melectini) is described and figured from northern Yemen and southwestern Saudi Arabia. Thyreus shebicus Engel, sp. n. is a relatively small species superficially similar to the widespread and polytypic species T. ramosus (Lepeletier de Saint Fargeau) and T. ramosellus (Cockerell) but more closely allied to various African forms on the basis of the male genitalia. The species is distinguished from its congeners on the basis of coloration pattern, male hind leg structure, and particularly male terminalia.     

Molecular identification of species of the genus Euglossa Latreille (Hymenoptera: Apidae, Euglossini)

Euglossine bees interact with more than 60 plant families of the Neotropical region. The richness and abundance of these bees have been intensively studied in different ecosystems using the methodology of capturing males with chemical baits. Females are poorly known for most of the species and morphological characters for their taxonomic classification have not yet been described. The purpose of this study was to use allozymes and restriction patterns of the mitochondrial regions 16S and Cyt b to identify species of Euglossa Latreille. Bees were collected while visiting Thevetia peruviana (Apocynaceae) flowers in five cities of the state of S?o Paulo, Brazil. Three Euglossa species were identified among the 305 individuals collected. Euglossa cordata (L.) was the only species found in all cities, while E. securigera Dressler and E. townsendi Cockerell were restricted to two and one cities respectively. EST-3 was a diagnostic marker, whereas ICD, MDH, ME and PGM were informative for species identification when used in combination. Restriction by VspI of the amplified 16S fragment differentiated the three species and showed intraspecific polymorphism for E. cordata and E. securigera. The Cyt b region showed distinctive patterns for E. townsendi but it was not possible to differentiate the other two species. Our results describe potentially useful genetic markers for the identification of Euglossa spp. at the species and group level.     

A new wild, pollinating bee species of the genus Tetraloniella from the Arabian Peninsula (Hymenoptera, Apidae)

A new species of the eucerine bee genus Tetraloniella Ashmead (Apinae: Eucerini) is described and figured from central Saudi Arabia and Qatar. Tetraloniella (Tetraloniella) persiciformissp. n. is distinguished on the basis of coloration, integumental sculpturing, male metafemoral structure, and male terminalia. A floral record of Pulicaria undulata (L.) C.A. Mey. (Compositae) is noted for some of the material. Females superficially resemble those of Tarsalia persica (Warncke) (Ancylaini) in overall coloration but can be distinguished by the typical generic and tribal characters.     

A new record of Thaumastobombus andreniformis Engel 2001 in Eocene amber (Hymenoptera: Apidae)

A new specimen of the rare fossil bee Thaumastobombus andreniformis Engel 2001 (Apidae: Apinae: Electrapini) is reported and figured from middle Eocene (Lutetian) Baltic amber. The new specimen, a female of the worker caste, agrees in every respect with the holotype except some morphometric differences. These minor size differences are likely related to the degree of sociality of T andreniformis.     

Diversity and distribution of orchid bees (Hymenoptera: Apidae) with a revised checklist of species

The aim of this study was to investigate the diversity and distribution patterns of orchid bees (Euglossina). Cluster and correlation analyses were applied to data extracted from 28 orchid-bee surveys throughout the Neotropical Region. The 28 sampling sites were grouped in three main biogeographic areas that roughly correspond to the Amazonian Basin, the Atlantic Forest and Central America. These three regions, as well as subregions within each of them, correspond approximately to biogeographic components identified through phylogeny-based analyses for other bees and organisms. The Amazonian Forest as a whole has the richest fauna and the highest levels of endemism. The Atlantic Forest, on the other hand, showed the poorest fauna and the lowest levels of endemism. However, a major neotropical biome, in which orchid bees are known to occur, has not been sampled yet, the savanna-like cerrado. At least 30% of the species are endemic to each biome. An updated checklist of the species of Euglossina is provided.