Hackeriapis oblonga, from PaDIL.

Belongs within: Megachilini.

Hackeriapis is an Australasian genus of relatively small resin bees, most of which (excepting some larger species) have strong transverse grooves on the second and third metasomal tergites (Michener 1965).

Resinous confusion
Published 12 February 2024

Australia (like most other parts of the world) is home to a wide diversity of solitary bees. These are often less remarked upon than their social relatives, but among those more likely to attract attention are the resin and leaf-cutter bees of the family Megachilidae. And among the more diverse subgroups of this family in Australia are the species of Hackeriapis.

Megachile tosticauda, copyright Laurence Sanders.

Recognised by Michener (2007) as a subgenus of the broad genus Megachile, Hackeriapis is an assemblage of resin bees found across Australia as well as in savannah habitats in New Guinea. Almost ninety species were listed in Hackeriapis by Michener (1965). King (1994) would later cut the subgenus down to a much more restricted seventeen species but the status of many of the remaining species remains undetermined. In the broad sense, Hackeriapis is hard to confidently define but its representatives are smaller resin bees with a characteristic cylindrical body form. They can typically be distinguished from other Australian megachilids by the presence of deep grooves across the dorsal surface of the second and third metasomal tergites, and/or a basal tooth on the tarsal claws (Michener 2007). Most species have a more or less greyish appearance, with pale pubescence over a black integument, though a number have a bright reddish patch at the end of the metasoma. Females may have the clypeus modified with the sides or the centre produced into grotesque horns (King 1994). Males may exhibit flattened expansions of the fore tarsi or distal segments of the antennae, possibly using them as banners to signal to females or other males (Houston 2018).

Megachile aurifrons stocking its nest, copyright Sam Gordon.

Nesting behaviour has been described for only a small number of Hackeriapis species but most examples known appear typical for resin bees (Houston 2018). Cells are constructed in pre-existing holes using resin that the female bee collects from the surrounding environment, such as gum seeping from eucalypts or from spinifex and grass trees. In those species with a modified clypeus, the projections may assist in carrying resin. In most species, each cell will contain a store of pollen pudding and a single egg. One Hackeriapis species, Megachile aurifrons, is exceptional in not constructing individual cells; instead, it fills a hollow with a uniform mass of pudding into which eggs are deposited in separate cavities. Communal nesting is not uncommon, particularly in smaller species, with multiple females constructing cells in close proximity.

Megachile canifrons, copyright Kerry Stuart.

The broader relationships of Hackeriapis have been the subject of some speculation. Because of the variability of its members, it has been suggested that other Australian Megachile subgenera may be derived within it. However, Hackeriapis species also bear a remarkable resemblance to North American megachilids of the subgenus Chelostomoides, raising the question of some sort of cross-Pacific connection. Gonzalez et al. (2019), in an analysis of phylogenetic relationships within Megachilidae, preferred an association of Hackeriapis representatives with other Australian taxa rather than with Chelostomoides. Are the shared features of Hackeriapis and Chelostomoides the result of convergence, perhaps reflecting their shared associations with arid environments? If so, what is it about a dry landscape that makes bees get groovy?

The fire-tailed resin bee
Published 22 April 2024

The type species of Hackeriapis is H. rhodura, first described from Queensland by T. D. A. Cockerell in 1906. It has since been recorded in northern New South Wales and is found eastward of the Great Dividing Range (King 1994). Individuals of H. rhodura have orange-red integument on the apical segments of the metasoma, covered with an orange-gold tomentum that does not form a distinct spot. The clypeus is not distinctly modified, being evenly rounded medially, and the mesoscutum has relatively sparse punctures towards the front and sides. Males have white branched hairs covering the second and third sternites of the metasoma but these are relatively short on the third sternite, and the sixth tergite has an apically bilobed carina.

Megachile rhodura males roosting, copyright Margaret Hvass.

Information on the natural history of H. rhodura seems to be sparse. King (1994) records specimens collected from eucalypts and blackthorn Bursaria spinosa. Rayment (1935) notes that the Queensland-based entomologist Henry Hacker observed individuals of both sexes collecting kino gum from a wound in a eucalypt bole. Eucalypt kino is typically a dark blood-red colour that can potentially give wounded trees an alarming appearance. Nest holes sealed with such gum could be similarly noteworthy.

Systematics of Megachile (Hackeriapis)

Characters (from Michener 1965): Usually small, slender bodied, parallel sided; posterior end of scutellum sloping (not strongly curved down), metanotum sloping (not vertical), basal part of propodeum subhorizontal; postgradular grooves usually present on second and third terga, usually not fasciate; terga often with apical pubescent fasciae; head little to much developed posteriorly, preoccipital carina occasionally present; pronotal lobe carinate.

<==Hackeriapis Cockerell 1922M65
|--*H. rhodura (Cockerell 1906) [=Megachile rhodura, Chalicodoma (*H.) rhodura]M65
|--H. alani (Cockerell 1929) [=Megachile (Hackeriapis) alani, Chalicodoma (H.) alani]M65
|--H. alleynae (Rayment 1935) [=Megachile (Hackeriapis) alani, Chalicodoma (H.) alleynae]M65
|--H. apicata (Smith 1853) [=Megachile (Hackeriapis) apicata, Chalicodoma (H.) apicata]M65
|--H. apposita (Rayment 1939) [=Megachile (Hackeriapis) apposita, Chalicodoma (H.) apposita]M65
|--H. argentifer (Cockerell 1910) [=Megachile (Hackeriapis) argentifer, Chalicodoma (H.) argentifer]M65
|--H. atrella (Cockerell 1906) [=Megachile (Hackeriapis) atrella, Chalicodoma (H.) atrella]M65
|--H. aurifrons (Smith 1853) [=Megachile (Hackeriapis) aurifrons, Chalicodoma (H.) aurifrons]M65
|--H. axillaris (Meade-Waldo 1915) [=Megachile (Hackeriapis) axillaris, Chalicodoma (H.) axillaris]M65
|--H. barvonensis (Cockerell 1914) [=Megachile (Hackeriapis) barvonensis, Chalicodoma (H.) barvonensis]M65
|--H. beutenmulleri (Cockerell 1907) [=Megachile (Hackeriapis) beutenmulleri, Chalicodoma (H.) beutenmulleri]M65
|--H. calida (Smith 1879) [=Megachile (Hackeriapis) calida, Chalicodoma (H.) calida]M65
|--H. callura (Cockerell 1914)M65 (see below for synonymy)
|--H. canifrons (Smith 1853) [=Megachile (Hackeriapis) canifrons, Chalicodoma (H.) canifrons]M65
|--H. cliffordi (Rayment 1953) [=Megachile (Hackeriapis) cliffordi, Chalicodoma (H.) cliffordi]M65
|--H. clypeata (Smith 1853) (see below for synonymy)M65
|--H. derelicta (Cockerell 1913) [=Megachile (Hackeriapis) derelicta, Chalicodoma (H.) derelicta]M65
|--H. dinognatha (Cockerell 1929) [=Megachile (Hackeriapis) dinognatha, Chalicodoma (H.) dinognatha]M65
|--H. erythropyga (Smith 1853) [=Megachile (Hackeriapis) erythropyga, Chalicodoma (H.) erythropyga]M65
|--H. eucalypti (Cockerell 1910) [=Megachile (Hackeriapis) eucalypti, Chalicodoma (H.) eucalypti]M65
|--H. ferox (Smith 1879) [=Megachile (Hackeriapis) ferox, Chalicodoma (H.) ferox]M65
|--H. franki (Friese 1920) [=Thaumatosoma franki, Chalicodoma (Hackeriapis) franki]M65
|--H. fultoni (Cockerell 1913) [=Megachile (Hackeriapis) fultoni, Chalicodoma (H.) fultoni]M65
|--H. fulvomarginata (Cockerell 1906) [=Megachile (Hackeriapis) fulvomarginata, Chalicodoma (H.) fulvomarginata]M65
|--H. fumipennis (Smith 1868) [=Megachile (Hackeriapis) fumipennis, Chalicodoma (H.) fumipennis]M65
|--H. gilbertiella (Cockerell 1910) [=Megachile (Hackeriapis) gilbertiella, Chalicodoma (H.) gilbertiella]M65
|--H. hackeri (Cockerell 1913) [=Megachile (Hackeriapis) hackeri, Chalicodoma (H.) hackeri]M65
|--H. hardyi (Cockerell 1929) [=Megachile (Hackeriapis) hardyi, Chalicodoma (H.) hardyi]M65
|--H. heliophila (Cockerell 1913) [=Megachile (Hackeriapis) heliophila, Chalicodoma (H.) heliophila]M65
|--H. henrici (Cockerell 1907) [=Megachile (Hackeriapis) henrici, Chalicodoma (H.) henrici]M65
|--H. holura (Cockerell 1912) [=Megachile (Hackeriapis) holura, Chalicodoma (H.) holura]M65
|--H. horatii (Cockerell 1913) [=Megachile (Hackeriapis) horatii, Chalicodoma (H.) horatii]M65
|--H. latericauda (Cockerell 1921) [=Megachile (Hackeriapis) latericauda, Chalicodoma (H.) latericauda]M65
|--H. latipes (Smith 1853) [=Megachile (Hackeriapis) latipes, Chalicodoma (H.) latipes]M65
|--H. leeuwinensis (Meade-Waldo 1915) [=Megachile (Hackeriapis) leeuwinensis, Chalicodoma (H.) leeuwinensis]M65
|--H. leucopyga (Smith 1853) [=Megachile (Hackeriapis) leucopyga, Chalicodoma (H.) leucopyga]M65
|--H. longiceps (Meade-Waldo 1915) [=Megachile (Hackeriapis) longiceps, Chalicodoma (H.) longiceps]M65
|--H. lucidiventris (Smith 1853) [=Megachile (Hackeriapis) lucidiventris, Chalicodoma (H.) lucidiventris]M65
|--H. mackayensis (Cockerell 1910) [=Megachile (Hackeriapis) mackayensis, Chalicodoma (H.) mackayensis]M65
|--H. macleayi (Cockerell 1907) [=Megachile (Hackeriapis) macleayi, Chalicodoma (H.) macleayi]M65
|--H. micrerythrura (Cockerell 1910) [=Megachile (Hackeriapis) micrerythrura, Chalicodoma (H.) micrerythrura]M65
|--H. modesta (Smith 1862) [=Megachile (Hackeriapis) modesta, Chalicodoma (H.) modesta]M65
|--H. monkmani (Rayment 1935) [=Megachile (Hackeriapis) monkmani, Chalicodoma (H.) monkmani]M65
|--H. mundifica (Cockerell 1921) [=Megachile (Hackeriapis) mundifica, Chalicodoma (H.) mundifica]M65
|--H. nasuta (Smith 1868) [=Megachile (Hackeriapis) nasuta, Chalicodoma (H.) nasuta]M65
|--H. nigrovittata (Cockerell 1906) [=Megachile (Hackeriapis) nigrovittata, Chalicodoma (H.) nigrovittata]M65
|--H. ‘nuda’ (Rayment 1935)M65 [=M. lucidiventris nuda non Mitchell 1930R35, Chalicodoma (Hackeriapis) nudaM65]
|--H. oblonga (Smith 1879) [=Megachile (Hackeriapis) oblonga, Chalicodoma (H.) oblonga]M65
|--H. oculiformis (Rayment 1956) [=Megachile (Hackeriapis) oculiformis, Chalicodoma (H.) oculiformis]M65
|--H. oculipes (Cockerell 1910) [=Megachile (Hackeriapis) oculipes, Chalicodoma (H.) oculipes]M65
|--H. ordinaria (Smith 1853) [=Megachile (Hackeriapis) ordinaria, Chalicodoma (H.) ordinaria]M65
|--H. papuae (Michener 1965) [=Chalicodoma (Hackeriapis) papuae]M65
|--H. paracallida (Rayment 1935) [=Megachile (Hackeriapis) paracallida, Chalicodoma (H.) paracallida]M65
|--H. pararhodura (Cockerell 1910) [=Megachile (Hackeriapis) pararhodura, Chalicodoma (H.) pararhodura]M65
|--H. paratasmanica (Rayment 1955) [=Megachile (Hackeriapis) paratasmanica, Chalicodoma (H.) paratasmanica]M65
|--H. phillipensis (Rayment 1935) [=Megachile (Hackeriapis) phillipensis, Chalicodoma (H.) phillipensis]M65
|--H. preissi (Cockerell 1910) [=Megachile (Hackeriapis) preissi, Chalicodoma (H.) preissi]M65
|--H. punctata (Smith 1853) [=Megachile (Hackeriapis) punctata, Chalicodoma (H.) punctata]M65
|--H. ramulipes (Cockerell 1913) [=Megachile (Hackeriapis) ramulipes, Chalicodoma (H.) ramulipes]M65
|--H. relicta (Cockerell 1913) [=Megachile (Hackeriapis) relicta, Chalicodoma (H.) relicta]M65
|--H. revicta (Cockerell 1913) [=Megachile (Hackeriapis) revicta, Chalicodoma (H.) revicta]M65
|--H. rufapicata (Cockerell 1929) [=Megachile (Hackeriapis) rufapicata, Chalicodoma (H.) rufapicata]M65
|--H. rufolobata (Cockerell 1913) [=Megachile (Hackeriapis) rufolobata, Chalicodoma (H.) rufolobata]M65
|--H. rugosa (Smith 1879) [=Megachile (Hackeriapis) rugosa, Chalicodoma (H.) rugosa]M65
|--H. semicandens (Cockerell 1910) [=Megachile (Hackeriapis) semicandens, Chalicodoma (H.) semicandens]M65
|--H. semiluctuosa (Smith 1853) (see below for synonymy)M65
|--H. sericeicauda (Cockerell 1910) [=Megachile (Hackeriapis) sericeicauda, Chalicodoma (H.) sericeicauda]M65
|--H. silvestris (Erickson & Rayment 1951)M65 (see below for synonymy)
|--H. simpliciformis (Cockerell 1918) [=Megachile (Hackeriapis) simpliciformis, Chalicodoma (H.) simpliciformis]M65
|--H. speluncarum (Meade-Waldo 1915) [=Megachile (Hackeriapis) speluncarum, Chalicodoma (H.) speluncarum]M65
|--H. stalkeri (Cockerell 1910) [=Megachile (Hackeriapis) stalkeri, Chalicodoma (H.) stalkeri]M65
|--H. subabdominalis (Rayment 1935) [=Megachile (Hackeriapis) subabdominalis, Chalicodoma (H.) subabdominalis]M65
|--H. subremotula (Rayment 1934) [=Megachile (Hackeriapis) subremotula, Chalicodoma (H.) subremotula]M65
|--H. subserricauda (Rayment 1935) [=Megachile (Hackeriapis) subserricauda, Chalicodoma (H.) subserricauda]M65
|--H. suffusipennis (Cockerell 1906) [=Megachile (Hackeriapis) suffusipennis, Chalicodoma (H.) suffusipennis]M65
|--H. tasmanica (Cockerell 1916) [=Megachile (Hackeriapis) tasmanica, Chalicodoma (H.) tasmanica]M65
|--H. tomentella (Cockerell 1906) [=Megachile (Hackeriapis) tomentella, Chalicodoma (H.) tomentella]M65
|--H. tosticauda (Cockerell 1912)H18, M65 [=Megachile (Hackeriapis) tosticaudaH18, Chalicodoma (H.) tosticaudaM65]
|--H. trichognatha (Rayment 1930) [=Megachile (Hackeriapis) trichognatha, Chalicodoma (H.) trichognatha]M65
|--H. trichomarginata (Rayment 1930) [=Megachile (Hackeriapis) trichomarginata, Chalicodoma (H.) trichomarginata]M65
|--H. turneri (Meade-Waldo 1913)M65 (see below for synonymy)
|--H. ustulata (Smith 1862) [=Megachile (Hackeriapis) ustulata, Chalicodoma (H.) ustulata]M65
|--H. victoriae (Cockerell 1913) [=Megachile (Hackeriapis) victoriae, Chalicodoma (H.) victoriae]M65
`--H. wilsoni (Cockerell 1929) [=Megachile (Hackeriapis) wilsoni, Chalicodoma (H.) wilsoni]M65

Hackeriapis callura (Cockerell 1914)M65 [=Thaumatosoma callurumM65, Chalicodoma (Hackeriapis) calluraM65, Megachile (H.) calluraH18]

Hackeriapis clypeata (Smith 1853) [=Megachile (Hackeriapis) clypeata, Chalicodoma (H.) clypeata; incl. M. grandis Rayment 1934 non Lepeletier 1841]M65

Hackeriapis semiluctuosa (Smith 1853) [=Megachile (Hackeriapis) semiluctuosa, Chalicodoma (H.) semiluctuosa; incl. M. blackburnii Froggatt 1893]M65

Hackeriapis silvestris (Erickson & Rayment 1951)M65 [=Megachile gilbertiella silvestrisER51, Chalicodoma (Hackeriapis) silvestrisM65]

Hackeriapis turneri (Meade-Waldo 1913)M65 [=Thaumatosoma turneriM65, Chalicodoma (Hackeriapis) turneriM65, Megachile (H.) turneriH18]

*Type species of generic name indicated


[ER51] Erickson, R., & T. Rayment. 1951. Simple social bees of Western Australia. Western Australian Naturalist 3 (3): 45–58.

Gonzalez, V. H., G. T. Gustafson & M. S. Engel. 2019. Morphological phylogeny of Megachilini and the evolution of leaf-cutter behavior in bees (Hymenoptera: Megachilidae). Journal of Melittology 85: 1–123.

[H18] Houston, T. 2018. A Guide to Native Bees of Australia. CSIRO Publishing.

King, J. 1994. The bee family Megachilidae (Hymenoptera: Apoidea) in Australia. I. Morphology of the genus Chalicodoma Lepeletier, and a revision of the subgenus Hackeriapis Cockerell. Invertebrate Taxonomy 8: 1373–1419.

[M65] Michener, C. D. 1965. A classification of the bees of the Australian and South Pacific regions. Bulletin of the American Museum of Natural History 130: 1–362.

Michener, C. D. 2007. The Bees of the World 2nd ed. John Hopkins University Press: Baltimore.

[R35] Rayment, T. 1935. A Cluster of Bees: Sixty essays on the life-histories of Australian bees, with specific descriptions of over 100 new species. Endeavour Press: Sydney.

Leave a comment

Your email address will not be published. Required fields are marked *