Scarabaeini

Sacred scarab beetles Scarabaeus sacer, copyright Hectonichus.

Belongs within: Scarabaeinae.

The Scarabaeini are an Old World group of dung beetles with a profemoral setal brush composed of separate clumps of long and short setae. The hind legs are typically slender, with the hind tibia not widening significantly along their length.

Members of the Scarabaeini are commonly rollers, collecting dung by forming it into a ball and pushing it backwards with the hind legs (Philips et al. 2004). Famously, the sacred scarab Scarabaeus sacer of the Mediterranean region was revered by the ancient Egyptians who saw this behaviour as reminiscent of the sun crossing the heavens. However, species of Sceliages lay their eggs on dead millipedes which they push into place with their head.

Dung beetles
Published 17 April 2013
Flat-headed dung beetles Pachylomerus femoralis with a ball of the good stuff, photographed by Guido Coza.

The dung beetles of the Scarabaeini include 146 species found in Africa and Asia, classified by Forgie et al. (2006) into three genera: Pachysoma, Pachylomerus and Scarabaeus, with the last including the vast majority of species. The Scarabaeus species are perhaps the most famous of all dung beetles, renowned since ancient history when Egyptians saw a dung beetle rolling a ball of dung along the ground as a metaphor for the movement of the sun through the heavens*. Dung beetles collect their turd balls to use as food for themselves or for their larvae. Ball-rolling is not unique to the Scarabaeini as a method of transporting dung, however (it is also done by members of other dung beetle tribes), nor do all Scarabaeini species engage in ball-rolling.

*It perhaps does not say much for the standard of ancient Egyptian public sanitation that they were apparently so willing to believe that the ultimate source of all life on the planet was a giant mass of burning poop.

Flightless orange dung beetle Pachysoma denticolle, photographed by Alex Dreyer.

The flightless dung beetles of the genus Pachysoma, for instance, transport their food by dragging it along between their hind legs. Pachysoma species are also less choosy than other Scarabaeini, feeding not just on dung but all manner of organic detritus. They have specialisations allowing them to feed on drier food particles than other Scarabaeini, suitable for their arid habitats in southern Africa. In contrast, species of the subgenus Sceliages within Scarabaeus are the epicures of the scarabaein world: they feed entirely on dead millipedes, which they push along in front of themselves bulldozer-style (Forgie et al. 2005). Relatively few species of Scarabaeini feed by burrowing directly alongside piles of dung where they lay, but this may be done by Pachylomerus and Scarabaeus galenus (both of which may also transport food).

Individual of Sceliages transporting a millipede, photographed by Shaun Forgie.

Most Scarabaeini are active during the day, but a small number such as Scarabaeus satyrus are nocturnal in habit. In the phylogenetic analyses conducted by Forgie et al. (2005), these nocturnal species usually formed a single clade. Had the ancient Egyptians observed the nocturnal dung beetles as well, they could have presented us with a sky full of poo at all hours.

Systematics of Scarabaeini

Synapomorphies (from Philips et al. 2004): Labial paraglossa strut distinctly bifurcate at proximal apex; declivous region of mentum broad and short; cervical sclerite with setal brush concentrated along apical and lateral margin; cervical sclerite apodeme obliquely oriented to lateral edge; profemoral setal brush composed of both long and short setae in separate clumps; midcoxae strongly oblique.

<==ScarabaeiniPPS04
    |--Kheper subaeneusPPS04
    |--SceliagesPPS04
    |--MnematiumPPS04
    |--Coproecus Reiche 1841CW92
    |    `--*C. hemisphericus (Guérin-Méneville 1830) [=Circellium hemisphaericum]CW92
    |--PachylomeraPPS04
    |    |--P. femoralis (Kirby 1828)B14
    |    `--P. opacaB14
    |--Boletoscapter Matthews 1974CW92
    |    |--*B. cornutus (Matthews 1974) [=Cephalodesmius cornutus]CW92
    |    `--B. furcatus Matthews 1974CW92
    |--Mentophilus Castelnau 1840 [incl. Aulacium Reiche 1841]CW92
    |    |--*M. hollandiae Castelnau 1840CW92 [incl. *Aulacium carinatum Reiche 1841CW92, Menthophilus carinatusM86]
    |    `--M. subsulcatus Sharp 1873CW92
    |--Pseudignambia Paulian & Pluot-Sigwalt 1984CW92
    |    |--*P. mimerops (Matthews 1974) [=Ignambia mimerops]CW92
    |    `--P. squamata (Matthews 1974) [=Ignambia squamata]CW92
    |--Aptenocanthon Matthews 1974CW92
    |    |--*A. hopsoni (Carter 1936) [=Panelus hopsoni]CW92
    |    |--A. monteithi Storey 1984CW92
    |    `--A. rossi Matthews 1974CW92
    |--Aulacopris White 1859CW92
    |    |--*A. reichei White 1859CW92
    |    |--A. matthewsi Storey 1986CW92
    |    `--A. maximus Matthews 1974CW92
    |--Canthonosoma Macleay 1871 [incl. Homodesmius Sharp 1873]CW92
    |    |--*C. mastersii Macleay 1871 [incl. Homodesmius planus Sharp 1873]CW92
    |    |--C. castelnaui (Harold 1868) [=Cephalodesmius castelnaui]CW92
    |    `--C. macleayi (Harold 1868) [=Cephalodesmius macleayi, *Homodesmius macleayi; incl. H. haroldi Sharp 1873]CW92
    |--Labroma Sharp 1873CW92
    |    |--*L. horrens Sharp 1873CW92
    |    |--L. tuberculata (Waterhouse 1874) [=Menthophilus tuberculatus]CW92
    |    `--L. umbratilis Matthews 1974CW92
    |--Sauvagesinella Paulian 1934CW92
    |    |--*S. monstrosa Paulian 1934CW92
    |    |--S. becki (Paulian 1934) [=Tesserodon becki]CW92
    |    `--S. palustris Matthews 1934CW92
    |--Monoplistes Lansberge 1874CW92
    |    |--*M. haroldi Lansberge 1874CW92
    |    |--M. curvipes Lea 1923CW92
    |    |--M. leai Paulian 1934CW92
    |    |--M. occidentalis (Macleay 1888) [=Temnoplectron occidentale; incl. T. lucidum Macleay 1888]CW92
    |    |--M. phanophilus Lea 1923CW92
    |    `--M. tropicus Lea 1923CW92
    |--Diorygopyx Matthews 1974CW92
    |    |--*D. tibialis (Macleay 1871) [=Temnoplectron tibiale]CW92
    |    |--D. asciculifer Matthews 1974CW92
    |    |--D. cuspidatus Matthews 1974CW92
    |    |--D. duplodentatus Matthews 1974CW92
    |    |--D. incomptus Matthews 1974CW92
    |    |--D. incrassatus Matthews 1974CW92
    |    |--D. niger Matthews 1974CW92
    |    `--D. simpliciclunis Matthews 1974CW92
    |--Temnoplectron Westwood 1842CW92
    |    |--*T. rotundum Westwood 1842CW92
    |    |--T. aeneopiceum Matthews 1974CW92
    |    |--T. bornemisszai Matthews 1974CW92
    |    |--T. disruptum Matthews 1974CW92
    |    |--T. diversicolle Blackburn 1894CW92
    |    |--T. involucre Matthews 1974CW92
    |    |--T. laeve (Castelnau 1840) [=Hyboma laeve]CW92
    |    |--T. laevigatum Matthews 1974CW92
    |    |--T. politulum Macleay 1887 [incl. T. reyi Paulian 1934]CW92
    |    `--T. subvolitans Matthews 1974CW92
    |--Tesserodon Hope 1837CW92
    |    |--*T. novaehollandiae (Fabricius 1775)CW92 (see below for synonymy)
    |    |--T. angulatum Westwood 1842 [=T. angulatus]CW92
    |    |--T. erratum Sotrey 1991CW92
    |    |--T. feehani Storey 1991CW92
    |    |--T. gestroi Lansberge 1855CW92
    |    |--T. granulatum Matthews 1974CW92
    |    |--T. henryi Storey 1991CW92
    |    |--T. hilleri Storey 1991CW92
    |    |--T. intricatum Lea 1923 [=T. intricatus]CW92
    |    |--T. pilicrepus Matthews 1974CW92
    |    |--T. simplicipunctatum Storey 1991CW92
    |    |--T. tenebroides Matthews 1974CW92
    |    `--T. variolosum Macleay 1888CW92
    `--Scarabaeus Linnaeus 1758L58
         |--S. actaeon Linnaeus 1758L58
         |--S. aloeus Linnaeus 1758L58
         |--S. aquaticus Linnaeus 1758L58
         |--S. atlas Linnaeus 1758L58
         |--S. auratus Linnaeus 1758L58
         |--S. brunnus Linnaeus 1758L58
         |--S. calcaratus Linnaeus 1758L58
         |--S. capensis Linnaeus 1758L58
         |--S. caraboides Linnaeus 1758L58
         |--S. carinatus Linnaeus 1758L58
         |--S. carnifex Linnaeus 1758L58
         |--S. ceratoniae Linnaeus 1758L58
         |--S. cervus Linnaeus 1758L58
         |--S. chrysis Linnaeus 1758L58
         |--S. conspurcatus Linnaeus 1758L58
         |--S. cylindricus Linnaeus 1758L58
         |--S. deludensMF15
         |--S. didymus Linnaeus 1758L58
         |--S. erraticus Linnaeus 1758L58
         |--S. fasciatus Linnaeus 1758L58
         |--S. festivus Linnaeus 1758L58
         |--S. flavicornisPPS04
         |--S. fossor Linnaeus 1758L58
         |--S. fullo Linnaeus 1758L58
         |--S. gigas Linnaeus 1758L58
         |--S. haemorrhoidalis Linnaeus 1758L58
         |--S. hemipterus Linnaeus 1758L58
         |--S. hercules Linnaeus 1758L58
         |--S. horticola Linnaeus 1758L58
         |--S. indus Linnaeus 1758L58
         |--S. interruptus Linnaeus 1758L58
         |--S. lanigerus Linnaeus 1758L58
         |--S. lanius Linnaeus 1758L58
         |--S. laticollisKR91
         |--S. lineola Linnaeus 1758L58
         |--S. longimanus Linnaeus 1758L58
         |--S. maurus Linnaeus 1758L58
         |--S. melolontha Linnaeus 1758L58
         |--S. mimas Linnaeus 1758L58
         |--S. molossus Linnaeus 1758L58
         |--S. nitidus Linnaeus 1758L58
         |--S. nobilis Linnaeus 1758L58
         |--S. nuchicornis Linnaeus 1758L58
         |--S. parallelipipedus Linnaeus 1758L58
         |--S. pilularius Linnaeus 1758L58
         |--S. punctatus Linnaeus 1758L58
         |--S. rufipes Linnaeus 1758L58
         |--S. sacer Linnaeus 1758B14
         |--S. scaber Linnaeus 1758L58
         |--S. semipunctatusKR91
         |--S. sepicola Linnaeus 1758L58
         |--S. simson Linnaeus 1758L58
         |--S. solstitialis Linnaeus 1758L58
         |--S. subterraneus Linnaeus 1758L58
         |--S. sylvanusB35
         |--S. syriacus Linnaeus 1758L58
         |--S. tridentatus Linnaeus 1758L58
         |--S. truncatusB35
         |--S. typhoeus Linnaeus 1758L58
         |--S. typhonKR91
         `--S. variabilis Linnaeus 1758L58

*Tesserodon novaehollandiae (Fabricius 1775)CW92 [=Scarabaeus novaehollandiaeCW92, T. hollandiaeM86; incl. T. piceum Hope 1842CW92]

*Type species of generic name indicated

References

[B35] Boisduval, J. B. 1835. Voyage de Découvertes de l’Astrolabe. Exécuté par ordre du Roi, pendant les années 1826–1827–1828–1829, sous le commandement de M. J. Dumont d’Urville. Faune entomologique de l’océan Pacifique, avec l’illustration des insectes nouveaux recueillis pendant le voyage vol. 2. Coléoptères et autres ordres. J. Tastu: Paris.

[B14] Bouchard, P. (ed.) 2014. The Book of Beetles: A lifesize guide to six hundred of nature’s gems. Ivy Press: Lewes (United Kingdom).

[CW92] Cassis, G., & T. A. Weir. 1992. Scarabaeinae. In: Houston, W. W. K. (ed.) Zoological Catalogue of Australia vol. 9. Coleoptera: Scarabaeoidea pp. 106–173. AGPS Press: Canberra.

Forgie, S. A., U. Kryger, P. Bloomer & C. H. Scholtz. 2006. Evolutionary relationships among the Scarabaeini (Coleoptera: Scarabaeidae) based on combined molecular and morphological data. Molecular Phylogenetics and Evolution 40: 662–678.

Forgie, S. A., T. K. Philips & C. H. Scholtz. 2005. Evolution of the Scarabaeini (Scarabaeidae: Scarabaeinae). Systematic Entomology 30: 60–96.

[KR91] Krantz, G. W., L. A. Royce, R. R. Lowry & R. Kelsey. 1991. Mechanisms of phoretic specificity in Macrocheles (Acari: Macrochelidae). In: Dusbábek, F., & V. Bukva (eds) Modern Acarology: Proceedings of the VIII International Congress of Acarology, held in České Budĕjovice, Czechoslovakia, 6–11 August 1990 vol. 2 pp. 561–569. SPB Academic Publishing: The Hague.

[L58] Linnaeus, C. 1758. Systema Naturae per Regna Tria Naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Laurentii Salvii: Holmiae.

[M86] Masters, G. 1886. Catalogue of the described Coleoptera of Australia. Part III. Proceedings of the Linnean Society of New South Wales, series 2, 1 (1): 21–126.

[MF15] McKenna, D. D., B. D. Farrell, M. S. Caterino, C. W. Farnum, D. C. Hawks, D. R. Maddison, A. E. Seago, A. E. Z. Short, A. F. Newton & M. K. Thayer. 2015. Phylogeny and evolution of Staphyliniformia and Scarabaeiformia: forest litter as a stepping stone for diversification of nonphytophagous beetles. Systematic Entomology 40: 35–60.

[PPS04] Philips, T. K., E. Pretorius & C. H. Scholtz. 2004. A phylogenetic analysis of dung beetles (Scarabaeinae: Scarabaeidae): unrolling an evolutionary history. Invertebrate Systematics 18: 53–88.

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