The Operating of the Termites

I do not know the way many individuals would profess to have a favorite genus of termites. Which is a disgrace, as a result of there are some actual stand-out examples. Snapping termites, magnetic termites, glue-spraying termites… For my very own half, although, I’ve a selected fondness for the Australian harvester termites of the genus Drepanotermes.

Troopers and staff of Drepanotermes perniger, copyright Jean Hort.

Almost two dozen species of Drepanotermes are discovered on the Australian continent to which they’re distinctive (Watson & Perry 1981). They’re arid-environment specialists, being most numerous within the northern a part of Australia. My causes for being so keen on them are, I am going to admit, decidedly prosaic. The employee caste of most termite species could be very troublesome if not not possible to determine taxonomically; one termite employee often seems to be very very similar to one other. Drepanotermes staff, nevertheless, are completely different. The identify Drepanotermes might be translated as “operating termite” and, as befits their identify, Drepanotermes of all castes stand out for his or her distinctly lengthy legs. Troopers of Drepanotermes even have distinctively formed mandibles that are sickle-shaped and have a single projecting tooth on the interior margin. They’re much like troopers of the associated genus Amitermes (of which Drepanotermes could signify a derived subclade) however the mandibles of Amitermes are typically straighter and extra sturdy.

The lengthy legs of Drepanotermes mirror their lively harvester life. Employees will emerge from the nest at evening searching for meals to hold again dwelling. Within the pink centre of Australia they are going to primarily accumulate spinifex; they can even take fallen leaves, tree bark and the like. Troopers maintain guard whereas the employees forage. I’ve discovered them clustered round a nest entrance of a night, simply their heads poking out to snap at passers-by. Employees could wander as much as about half a metre from the nest entrance as they forage. The concentrations of vegetable matter produced by Drepanotermes storing meals sources of their nest could kind a major issue within the nutrient profile of areas the place they’re discovered.

Alate and troopers of Drepanotermes rubriceps, copyright Jean Hort.

Relying on species and circumstance, the nests of Drepanotermes could also be mounds or totally subterranean with the latter being the bulk choice. They like compact soils comparable to clay although they could burrow by means of looser soils the place there’s a denser subsoil. Drepanotermes could assemble their very own nest or transfer into nests constructed by different termites. One aptly named species, D. invasor, appears to take over pre-existing nests as a rule. Subterranean nests are organized as a sequence of chambers about 5 to 10 centimetres in diameter related by tunnels. These chambers could also be organized vertically, one under one other, or they could kind a rambling transverse community. Above floor, subterranean nests could also be seen as an open circle devoid of vegetation. The bottom in these circles is tough as concrete and should stay clear for many years after the precise nest has gone. Walsh et al. (2016) consult with the stays of nests protruding above floor alongside automobile tracks after the soil round them has worn down. Native individuals have an extended historical past of benefiting from the open area supplied by termite nests, comparable to to maneuver extra simply by means of scrub or as resting or working locations.

The alate castes of Drepanotermes are typically poorly identified. Indications are that mature reproductives spend little time within the mother or father nest earlier than leaving to breed. For many species, breeding flights happen in late summer time. Alates could emerge both by day or evening. The time of emergence appears to rely on the species; night-flying alates have distinctly bigger eyes than day-fliers. Sadly, as a result of alates have not often been collected in affiliation with a nest, we’re largely nonetheless unable to inform which alates belong to which species.

REFERENCES

Walsh, F. J., A. D. Sparrow, P. Kendrick & J. Schofield. 2016. Fairy circles or ghosts of termitaria? Pavement termites as different causes of round patterns in vegetation of desert Australia. Proceedings of the Nationwide Academy of Sciences of the USA 113 (37): E5365–E5367.

Watson, J. A. L., & D. H. Perry. 1981. The Australian harvester termites of the genus Drepanotermes (Isoptera: Termitinae). Australian Journal of Zoology, Supplementary Sequence 78: 1–153.