| Colletes validus | |
|---|---|
 | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Hymenoptera |
| Family: | Colletidae |
| Genus: | Colletes |
| Species: | C. validus |
| Binomial name | |
| Colletes validus Cresson, 1868 | |
Colletes validus, colloquially known as the blueberry cellophane bee, is a solitary, specialist bee in the family Colletidae. It is found primarily in eastern North America where it nests in sandy soils near ericaceous plants. [1]
C. validus is a medium-sized cellophane bee: females are 13–14 mm (0.51–0.55 in) long and males are 10–12 mm (0.39–0.47 in) long. [2] As is the case with members of the genus Colletes, all individuals have an S-shaped 2nd recurrent vein on the forewing. Most notably, C. validus males and females have an exaggerated malar space, giving the impression of a long, triangular face. [2] These two characteristics are diagnostic for C. validus within its range. [2] Males are covered densely with brown-yellowish hairs, giving fresh individuals a golden tinge. Females are less hairy and have reduced, but present scopa on the hind legs. It is similar to C. inaequalis Say and C. thoracicus Smith in appearance, range and phenology, however both of these species lack the distinctive long face. [1]
Its range extends from the Mid-Atlantic states north through New Hampshire and west through Michigan, with sparse records west to Wisconsin and north to Ontario. [2] C. validus is found throughout this range in sandy areas in proximity to ericaceous plants. [1] Records from Georgia and Florida likely belong to a newly described species, C. ultravalidus. [3]
C. validus is a univoltine bee that flies in early spring, coinciding with the flowering of Vaccinium and other ericaceous plants. [1] Near the southern extent of its range, adults fly in late-March, whereas further north flight occurs three to four weeks later. Males emerge precociously, i.e. a few days before females, and patrol nesting aggregations for mates. [1] They locate females via pheromones and mate at the nest site. Females commence nest excavation upon emergence and can use their emergence burrow as the start of their nest. A high degree of natal philopatry, i.e. nesting in your birthplace, is not uncommon for aggregating bees like C. validus. If females emerge too early and their pollen hosts have not started flowering, they can wait for the flowering to begin by sitting in their nest entrance and nectaring on available flowers of other plants. [4] Males disappear from the aggregation two to three weeks after emergence, leaving females as the only flying C. validus at the end of the season.
Nesting proceeds between four and six weeks, with each nest taking between five and ten days to complete. [1] Nests develop underground through the end of summer: eggs hatch into larvae, larvae grow on the semi-liquid provisions provided by the parent bee, and larvae pupate into adults. Anecdotal evidence from nests excavated early March [1] suggests that some prepupae (fully developed larvae) enter diapause before pupating. Whether these prepupa ever complete development is unknown as are the factors driving diapause initiation.
C. validus is a gregarious nester, meaning that nests often occur in aggregations (≈5 nests/m2 ). [4] Nesting sites are located in open sandy soils with sparse vegetation, often located close to their ericaceous hosts. Nests can be found on flat ground or south-facing slopes, but rarely under a closed canopy since C. validus prefers warm soils. Dense grass deters nesting. [1]
Surprisingly, C. validus is completely absent from surveys in the lowbush blueberry fields of Maine despite the tremendous abundance of host plant and presence of its generalist congener, C. inaequalis. [5] One explanation is that cold springtime soils discourage nesting, but this hypothesis has not been rigorously tested. Clearly, there are other factors besides open, sandy soil and host plant presence determining the nesting of C. validus within its range.
The common name of C. validus—blueberry cellophane bee—suggests a tighter relationship with its host plant than may actually exist. Evidence suggests it is not limited to blueberry (Vaccinium spp.) and it will forage for pollen broadly on a diversity of ericaceous plants with urceolate flowers, e.g. bearberry (Arctostaphylos uva-ursi) and black huckleberry (Gaylussacia baccata). [1] Pollen provisions can contain up to 15% Pinus spp. pollen and males and females have been observed visiting non-ericaceous plants (e.g. Acer rubrum, Prunus spp., Amelanchier spp.) for both pollen and nectar. [1] Part of the provisions are held within the crop during foraging and regurgitated upon return to the nest.
Nests descend from 17 to 60 cm (6.7 to 23.6 in) and measure ≈8 mm (0.31 in) in diameter. [4] Tunnel walls are not compacted since C. validus lacks a pygidial plate normally used for tamping down soil (a trait shared by all Colletes). [1] Cells are constructed at the end of short lateral tunnels arranged radially around the main tunnel. Laterals are constructed from the bottom to the top. [4] She proceeds by “painting” a Dufour's gland secretion mixed with saliva onto the walls of the cell using her short, bilobed glossa. [6] This mixture polymerizes into a polyester- or cellophane-like substance, which is where bees in the genus Colletes get their common name. [6] Cell construction primarily occurs at night and provisioning of the cell follows the next morning. [1] To provision the cell, the female first forages for ericaceous pollen and packs it into the bottom third of the cell. [4] Next, she adds nectar until a viscous soup is formed. [4] The waterproof cellophane lining of the cell permits the usage of semi-liquid provisions. Bacteria (Lactobacillus spp.) and/or yeast likely colonize the provisions based on visible gas bubbles and sour taste (pH 3–4). [1] Fermentation is common in other colletids that create liquid provisions, e.g. Ptiloglossa guinnae. [7] The female hangs a single egg (≈2.65mm in length) from the top of the cell so that the egg is not submerged in the provisions. [4] A maximum of five cells have been associated with any given nest. [1] [4] It is unknown whether females create more than one nest during their lifetime.
A variety of arthropods prey on C. validus nests. Adults of the blister beetle Tricrania sanguinipennis (Coleoptera) have been found in completed C. validus cells. [1] Bee flies (Bombylius mexicanus, B. pygmaeus in Beltsville, MD) have been observed ovipositing in the nest entrances of Colletes validus, but no larvae have been recovered from cells. [1] Robber flies (Nicocles pictus) predate adult C. validus (Batra 1980). [1] There are no known hymenopteran cleptoparasites of C. validus.
Entomologists have long-noted the citrus-like odor emitted by Colletes when handled. [4] Female C. validus will swarm around netted females emitting this odor. Past research has found that C. validus will aggregate around 1-terpinen-4-ol [4] and a 3:1:1: mixture of linalool-neral-geranial. [1] The exact aromatic profile of the Colletes attractant pheromone is unclear but could prove valuable for attracting C. validus to nesting sites for commercial pollination efforts.
C. validus can nest on footpaths through sand plain preserves or in open backyards built on sandy oak-pine forests (e.g. Barnstable County, Massachusetts), resulting in possible conflict with humans and pets. However, concern is unwarranted as C. validus is docile and will not sting unprovoked. Like many other bees, they will forage for salts from human sweat on hot days.
The potential of C. validus as a commercial blueberry pollinator has been acknowledged, but never fully explored. [4] C. validus has many of the characteristics of a bee that could be commercially managed for pollination including a preference for blueberry flowers, a phenology that almost exclusively overlaps with the bloom time of blueberry, and an ability to extract pollen from the deep, goblet flowers. [4] Understanding how to attract wild C. validus to nesting aggregations and initiate nesting would be a useful first step towards securing reliable pollination on farms.
Megachile rotundata, the alfalfa leafcutting bee, is a European bee that has been introduced to various regions around the world. As a solitary bee species, it does not build colonies or store honey, but is a very efficient pollinator of alfalfa, carrots, other vegetables, and some fruits. Because of this, farmers often use M. rotundata as a pollination aid by distributing M. rotundata prepupae around their crops. Each female constructs and provisions her own nest, which is built in old trees or log tunnels. Being a leafcutter bee, these nests are lined with cut leaves. These bees feed on pollen and nectar and display sexual dimorphism. This species has been known to bite and sting, but it poses no overall danger unless it is threatened or harmed, and its sting has been described as half as painful as a honey bee's.
Megachilidae is a cosmopolitan family of mostly solitary bees. Characteristic traits of this family are the restriction of their pollen-carrying structure to the ventral surface of the abdomen, and their typically elongated labrum. Megachilid genera are most commonly known as mason bees and leafcutter bees, reflecting the materials from which they build their nest cells ; a few collect plant or animal hairs and fibers, and are called carder bees, while others use plant resins in nest construction and are correspondingly called resin bees. All species feed on nectar and pollen, but a few are kleptoparasites, feeding on pollen collected by other megachilid bees. Parasitic species do not possess scopae. The motion of Megachilidae in the reproductive structures of flowers is energetic and swimming-like; this agitation releases large amounts of pollen.
Mason bee is a name now commonly used for species of bees in the genus Osmia, of the family Megachilidae. Mason bees are named for their habit of using mud or other "masonry" products in constructing their nests, which are made in naturally occurring gaps such as between cracks in stones or other small dark cavities. When available, some species preferentially use hollow stems or holes in wood made by wood-boring insects.
Osmia cornifrons, also known as the horned-face bee, is a species of solitary bee indigenous to Northern Asia. Physically, this species of bee is recognized for its horn-like extensions originating from its lower face. Populations of O. cornifrons have been recorded in multiple locations, including Japan, Korea, China, and Russia. O. cornifrons are more docile as compared to other species of bees and are less prone to sting when aggravated.
Vaccinium angustifolium, commonly known as the wild lowbush blueberry, is a species of blueberry native to eastern and central Canada and the northeastern United States, growing as far south as the Great Smoky Mountains and west to the Great Lakes region. Vaccinium angustifolium is the most common species of the commercially used wild blueberries and is considered the "low sweet" berry.
Hylaeus is a large and diverse cosmopolitan genus within the bee family Colletidae. This genus is also known as the yellow-faced bees or masked bees. This genus is the only truly globally distributed colletid, occurring on all continents except Antarctica.
Habropoda laboriosa, the southeastern blueberry bee, is a bee in the family Apidae. It is native to the eastern United States. It is regarded as the most efficient pollinator of southern rabbiteye blueberries, because the flowers require buzz pollination, and H. laboriosa is one of the few bees that exhibit this behavior. It is active for only a few weeks of the year, while the blueberries are in flower during early spring, when the temperature is warm and humid. H. laboriosa are solitary bees that live alone but nest in close proximity with other nests of their species. They have similar features to bumble bees, but they are smaller in size compared to them. H. laboriosa are arthropods so they have segmented bodies that are composed of the head, thorax, and abdomen.
With over 850 species, the genus Nomada is one of the largest genera in the family Apidae, and the largest genus of cuckoo bees. Cuckoo bees are so named because they enter the nests of a host and lay eggs there, stealing resources that the host has already collected. The name "Nomada" is derived from the Greek word nomas, meaning "roaming" or "wandering."
Xylocopa sonorina, the valley carpenter bee or Hawaiian carpenter bee, is a species of carpenter bee found from western Texas to northern California, and the eastern Pacific islands. Females are black while males are golden-brown with green eyes.
Colletes hederae, the ivy bee, is a species of plasterer bee belonging to the family Colletidae subfamily Colletinae.
Leioproctus fulvescens is a species of solitary bee belonging to the family Colletidae. This bee is endemic to the South Island of New Zealand, and its yellow-orange hair distinguishes it from all other New Zealand species of Leioproctus.
The Oriental carpenter bee, Xylocopa nasalis, or Xylocopa (Biluna) nasalis, is a species of carpenter bee. It is widely distributed in Southeast Asian countries. It is a major pollinator within its ecosystem, and is often mistaken for a bumblebee. The species leads a solitary lifestyle with a highly female-biased colony in the nest.
Xylocopa pubescens is a species of large carpenter bee. Females form nests by excavation with their mandibles, often in dead or soft wood. X. pubescens is commonly found in areas extending from India to Northeast and West Africa. It must reside in these warm climates because it requires a minimum ambient temperature of 18 °C (64 °F) in order to forage.
Macropis nuda is a ground nesting, univoltine bee native to northern parts of North America. Thus, this species cocoons as pupae and hibernates over the winter. The species is unusual as it is an oligolectic bee, foraging exclusively for floral oils and pollen from Primulaceae of the species Lysimachia ciliata.
Colletes halophilus, the sea aster mining bee, is a rare species of mining bee from the family Colletidae which is found around the margins of saltmarsh and other coastal habitats in south-eastern England and north-western Europe. It is threatened by rising sea levels and human development which reduce its food plant sea aster and destroy its nesting areas.
Colletes succinctus, the common colletes or heather colletes, is a species of Palearctic mining bee from the family Colletidae. It is part of the succinctus species group within the genus Colletes and is especially closely related to the ivy bee and the sea aster mining bee which are partially sympatric with C. succinctus but ecologically separate.
Stenoria analis, the ivy bee blister beetle, is a species of blister beetle from the family Meloidae which is found in western Europe and North Africa and is a specialist cleptoparasite of the ivy bee larvae. Its occurrence in regions outside of the known range of the ivy bee, for example in North Africa, suggest that it has other hosts.
Lasioglossum sordidum, also referred to as the small native bee, is one of the smallest native bees found in New Zealand.
Colletes cunicularius, the vernal colletes or spring mining bee, is a species of solitary bee from the family Colletidae which is widespread in the Palearctic from Britain to the Pacific Ocean which nests in areas of open, sandy soil.
Lasioglossum mataroa is a bee species that is found in New Zealand.
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