Changes With Age in Ultrastructure and Pheromone Content of Male Labial Glands in Some Bumble Bee Species (Hymneoptera, Apidae)

The cephalic part of the labial glands as the source of the male sexual pheromone in bumble bees is verified. Combined electron microscopic and thin layer chromato-graphic (TLC) studies of this gland of Pyrobombus lapidarius and P. hypnorum plus additional TLC tests on Megabombus hortorum revealed the pheromone production to differ gradually in time. During the first day of life the cells start to synthesize compounds of at least five main chemical classes, filling the acini of the gland at about the fourth day of life. During that process the cells flatten. The activity of the cells still remains at this time but gradually declines during the rest of the life of the bee. A smooth endoplasmic reticulum seems to be the cellular site of production

A simplified subgeneric classification of the bumblebees (genus Bombus)

A system of subgenera has been widely used for nearly a century to communicate ideas of relationships among bumblebee species. However, with 38 subgenera in recent lists for about 250 species, the system has come to be seen as too complicated. In this paper we suggest four criteria to guide the process of simplifying the subgeneric system, so that ideally subgenera should become: (1) monophyletic; (2) fewer; (3) diagnosable from morphology; and (4) names for important behavioural and ecological groups. Using a new strongly-supported estimate of phylogeny for almost all bumblebee species, we apply these criteria to reduce the system to 15 subgenera, and we assess the consequences. Ten new subgeneric synonyms are recognised. Keys to identify adult bumblebees to the simplified subgenera are provided for both sexes

Forward to the north: two Euro-Mediterranean bumblebee species now cross the Arctic Circle

International audienceIn recent decades, several animal and plant species have been in regression (population size decrease and geographical distribution shrinking). This loss of biodiversity can be due to various factors such as the destruction and fragmentation of habitat, urban development, pesticides or climate change. However, some species benefit from these changes and expand their distribution. Here we report observations (in 2013 and 2014) of two Euro-Mediterranean bumblebee species: Bombus terrestris for the first time and Bombus lapidarius, north of the Arctic Circle in Fennoscandia

Colour Patterns Do Not Diagnose Species: Quantitative Evaluation of a DNA Barcoded Cryptic Bumblebee Complex

Cryptic diversity within bumblebees (Bombus) has the potential to undermine crucial conservation efforts designed to reverse the observed decline in many bumblebee species worldwide. Central to such efforts is the ability to correctly recognise and diagnose species. The B. lucorum complex (Bombus lucorum, B. cryptarum and B. magnus) comprises one of the most abundant and important group of wild plant and crop pollinators in northern Europe. Although the workers of these species are notoriously difficult to diagnose morphologically, it has been claimed that queens are readily diagnosable from morphological characters. Here we assess the value of colour-pattern characters in species identification of DNA barcoded queens from the B. lucorum complex. Three distinct molecular operational taxonomic units were identified each representing one species. However, no uniquely diagnostic colour-pattern character state was found for any of these three molecular units and most colour-pattern characters showed continuous variation among the units. All characters previously deemed to be unique and diagnostic for one species were displayed by specimens molecularly identified as a different species. These results presented here raise questions on the reliability of species determinations in previous studies and highlights the benefits of implementing DNA barcoding prior to ecological, taxonomic and conservation studies of these important key pollinators

Colour Patterns Do Not Diagnose Species: Quantitative Evaluation of a DNA Barcoded Cryptic Bumblebee Complex

Cryptic diversity within bumblebees (Bombus) has the potential to undermine crucial conservation efforts designed to reverse the observed decline in many bumblebee species worldwide. Central to such efforts is the ability to correctly recognise and diagnose species. The B. lucorum complex (Bombus lucorum, B. cryptarum and B. magnus) comprises one of the most abundant and important group of wild plant and crop pollinators in northern Europe. Although the workers of these species are notoriously difficult to diagnose morphologically, it has been claimed that queens are readily diagnosable from morphological characters. Here we assess the value of colour-pattern characters in species identification of DNA-barcoded queens from the B. lucorum complex. Three distinct molecular operational taxonomic units were identified each representing one species. However, no uniquely diagnostic colour-pattern character state was found for any of these three molecular units and most colour-pattern characters showed continuous variation among the units. All characters previously deemed to be unique and diagnostic for one species were displayed by specimens molecularly identified as a different species. These results presented here raise questions on the reliability of species determinations in previous studies and highlights the benefits of implementing DNA barcoding prior to ecological, taxonomic and conservation studies of these important key pollinators

Bionomics and distribution of the stag beetle, Lucanus cervus (L.) across Europe

1. The European stag beetle, Lucanus cervus, is thought to be widely distributed across its range, but a detailed description of its occurrence is lacking. 2. Researchers in 41 countries were contacted and information sought on various life history characteristics of the insect. Data on adult body size were collected from seven countries. 3. Habitat associations differ between the United Kingdom and mainland Europe. Larvae are most commonly associated with oak, but the duration of the larval stage and the number of instars varies by up to 100% across Europe. 4. Adult size also varies; beetles from Spain, Germany, and the Netherlands are larger than those from Belgium or the UK. In the former countries, populations are composed mainly of large individuals, while in the UK, the majority of individuals are relatively small. Allometric relations between mandible size and total body length differ in Germany compared with the rest of Europe. 5. Distribution maps of the insect, split into records pre- and post-1970, from 24 countries are presented. While these inevitably suffer from recorder bias, they indicate that in only two countries, Croatia and Slovakia, does the insect seem to be increasing in range. 6. Our data suggest that the insect may be in decline across Europe, most likely due to habitat loss, and that conservation plans need to be produced that focus on the biology of the insect in the local area