Belongs within: Rhinotermitidae.
Contains: Termes, Nasutitermitinae, Syntermitinae, Microcerotermes, Amitermes.
The Termitinae are a group of termites possessing a ‘mixed segment’ in the intestine, with the mesenteron wall extending along one side of the gut. In many genera (the Amitermes group), the soldiers have elongate mandibles usually bearing a few large teeth. In the Termes–Capritermes group, soldiers’ mandibles are rod-like and adapted for rapid snapping to strike rather than slash at enemies. Some genera, such as Invasitermes, Protohamitermes and Orientotermes, lack soldiers and either live in association with other termites or have defensive roles filled by the workers. Molecular phylogenies also indicate that the Termitinae are paraphyletic to the nasute termites of the Nasutitermitinae and Syntermitinae (Inward et al. 2007).
Many species of Termitinae feed on humus rather than fresh vegetable matter.
Snap! goes the termite
Published 16 April 2013
For the subject of today’s post, I drew the termite subfamily Termitinae. Termites are extraordinary animals: socially complex, ecologically vital, dietically remarkable. Personally, I’m rather found of these communal cockroaches.
Termites of the family Termitidae (commonly referred to as the ‘higher termites’) differ from other, ‘lower’ termites in the nature of their gut biota (without which they would not be able to digest their cellulose diets): instead of having flagellated protozoa in their gut, termitids carry symbiotic bacteria. This difference in symbionts is reflected by a difference in diet. Higher termites feed on more decayed wood or plant matter than lower termites; some higher termites feed directly on organic-rich soil that contains little or no plant material (Inward et al. 2007). Subfamilies within the Termitidae are also distinguished on the basis of their gut anatomy: members of the Termitinae have what is called a ‘mixed segment’ on the outer edge of their intestine (Lo & Eggleton 2011). In the mixed segment, instead of the division between the mesenteron (the middle section of the intestine) and the proctodaeum (the posterior section) being simple and straight across, the mesenteron wall extends backwards along one side of the gut only; it has been suggested that the mixed segment functions to pump alkaline fluids into the gut, maintaining appropriate pH and fluid levels for the symbiotic bacteria in the hindgut (Bignell et al. 1983).
The Termitinae have also been distinguished on the basis of the morphology of their soldiers, with most genera having soldiers with elongate mandibles that have relatively few large teeth. These are used to bite and slash at threats to the colony. However, phylogenetic analyses have contradicted this distinction (Inward et al. 2007). The Termitinae are paraphyletic with regard to the Nasutitermitinae, who have developed a very different method of defense: the mandibles are reduced, and instead the front of the head is drawn out into an elongate ‘nose’. At the end of the ‘nose’ is a glandular opening from which the soldiers squirt a sticky glue at their opponents. Also nested within the Termitinae are the Syntermitinae whose soldiers combine both methods of defense: they retain sickle-shaped mandibles that are used to pierce the cuticle of attackers while the protruded glandular opening is used to apply toxic secretions. Chemical defenses are also not unknown among more standard termitines: soldiers of Globitermes sulphureus were dubbed ‘walking bombs’ by E. O. Wilson due to their explosive (and often self-destructive) discharge of toxic chemicals from hypertrophied labial gland reservoirs in the abdomen. It should also be noted that a small number of termitines do not produce soldiers at all: they may live in association with other soldier-producing termites, like the Australian Invasitermes, or they may feed on low-nutrient soils (presumably making the maintenance of a soldier caste too nutritionally expensive), like the Indomalayan genera Protohamitermes and Orientotermes.
Another mode of defense that is found only among the termitines (though phylogenetic analysis indicates that it has evolved multiple times) is the production of soldiers with elongate snapping mandibles. In these termites, soldiers store kinetic energy through muscular deformation of the mandibles, allowing them to be suddenly closed with great force (Prestwich 1984). So great is the force involved, in fact, that it seems to be not uncommon for the jaws to become completely crossed over as has happened to the individual at the top of this post. Snapping termites generally live in subterranean colonies, and even after the soldier has been ‘spent’ on the discharge of its mandibles, its body acts as a physical barrier in the confined tunnel. In some snapping termites, the mandibles are strongly asymmetrical, so the force of the closure is channelled through the left mandible only with doubled force. Asymmetrical snappers of the genus Neocapritermes, in fact, are able to knock out fairly large ants with a single blow. The video below shows a soldier of Planicapritermes attacking an ant:
Or you can see Neocapritermes in action in this video. Keep a close eye on the screen around the 20-second mark…
Systematics of Termitinae
<==Termitinae [Amitermitinae] |--+--EuchilotermesIVE07 | | |--E. tensusIVE07 | | `--+--E. umbraticolaIVE07 | | `--+--Furculitermes winifrediIVE07 | | `--+--ProcubitermesIVE07 | | | |--P. aburiensisK-WK92 | | | |--P. arboricolaIVE07 | | | `--P. undulansA50 | | `--OphiotermesIVE07 | | |--O. grandilabiusA50 | | `--O. ugandensisIVE07 | `--+--+--Apilitermes longicepsIVE07 | | `--+--Crenetermes albotarsalisIVE07 | | |--ThoracotermesIVE07 | | | |--T. brevinotusGN54 | | | `--T. macrothoraxA50 | | `--CubitermesIVE07 | | |--C. bilobatusA50 | | |--C. bulbifronsN55 | | |--C. exiguusN90 | | |--C. fungifaberS57 | | |--C. glebaeS57 | | |--C. intercalatusH79 | | |--C. sankurensisS57 | | |--C. severusN55 | | `--C. subcrenulatusS57 | `--+--OrthotermesIVE07 | | |--O. depressifronsIVE07 | | `--O. mansuetusA50 | `--+--Fastigitermes jucundusIVE07 | |--Proboscitermes tubuliferusIVE07, GE05 | |--BasidentitermesIVE07 | | |--B. aurivilliiA50 | | |--B. mactusIVE07 | | `--B. trilobatus Noirot 1955N55 | `--+--Lepidotermes pretoriensisA50 | `--+--UnguitermesIVE07 | | |--U. acutifronsIVE07 | | |--U. bidentatusA50 | | `--U. trispinosusIVE07 | `--NoditermesA50 | |--N. cristifronsS57 | |--N. curvatusGN54 | `--N. sinuosusA50 `--+--+--+--Cavitermes tuberosusIVE07, GE05 | | `--+--DihoplotermesIVE07 | | `--SpinitermesIVE07 | | |--S. nigrostomusA50 | | `--S. trispinosusIVE07 | `--+--TermesIVE07 | `--Capritermes Wasmann 1897IVE07, H42 | |--C. capricornisS57 | |--C. nemorosusS57 | `--C. schultzei Holmgren 1911H42 `--+--+--+--Verrucositermes tuberosusIVE07 | | `--+--Orientotermes emersoniIVE07 | | `--Protohamitermes globicepsIVE07 | `--+--NasutitermitinaeIVE07 | `--+--+--HomallotermesIVE07 | | | |--H. eleanoraeIVE07 | | | `--H. penangiA50 | | `--Pericapritermes Silvestri 1914IVE07, M91 | | |--*P. urgens Silvestri 1914M91 | | |--P. ceylonicusIVE07 | | |--P. latignathusSVT04 | | |--P. machadoi Noirot 1955N55 | | |--P. magnificusJK75 | | |--P. nitobeiIVE07 | | |--P. schultzei (Homgren 1911)M91 | | `--P. semarangiSVT04 | `--+--+--Quasitermes caprinusA50 | | `--+--Cornicapritermes mucronatusA50 | | `--MirocapritermesIVE07 | | |--M. concaveusSVT04 | | |--M. connectensSVT04 | | |--M. latignathusIVE07 | | `--M. prewensisSVT04 | `--+--ProcapritermesIVE07 | | |--P. longignathusSVT04 | | |--P. parasilvaticusSVT04 | | |--P. prosetigerSVT04 | | `--P. setigerIVE07 | `--+--Sinocapritermes mushaeIVE07 | `--DicuspiditermesIVE07 | |--D. garthwaiteiSVT04 | |--D. incolaIVE07 | |--D. makhamensisSVT04 | `--D. santschiiGE05 `--+--+--Tuberculitermes bycanistesIVE07 [incl. T. bycanistes var. guineensisA50] | `--+--SyntermitinaeIVE07 | |--+--Cephalotermes rectangularisIVE07 | | `--CylindrotermesIVE07 | | |--C. nordenskioeldiA50 | | `--C. parvignathusIVE07 | `--+--MicrocerotermesIVE07 | `--NeocapritermesIVE07 | | i. s.: N. angusticepsA50 | | N. opacus [=Capritermes opacus]S57 | |--N. taracuaIVE07 | `--+--N. talpaIVE07 | `--+--N. longinotusIVE07 | `--N. talpoidesIVE07 `--+--+--Planicapritermes planicepsIVE07 | `--+--Orthognathotermes wheeleriIVE07, A50 | `--+--Prohamitermes mirabilisIVE07 | `--GlobitermesIVE07 | |--G. globosusIVE07 | `--G. sulphureusA50 `--+--+--Angulitermes frontalisIVE07, A50 | `--PromirotermesIVE07 | |--P. connectensIVE07 | |--P. holmgreniA50 | `--P. redundansIVE07 `--+--+--Eremotermes fletcheriA50 | |--Synhamitermes quadricepsA50 | `--Pseudomicrotermes albonigerA50 `--+--AmitermesIVE07 `--GnathamitermesA50 |--G. perplexusN90 `--G. tubiformansN90 Termitinae incertae sedis: Mirotermes Wasmann 1897M91, H42 |--M. insignitus Hill 1942H42 |--M. ocellaris (Mjöberg 1920) [=Eutermes ocellaris]H42 |--M. odontomachus (Desneux 1905) [=Termes (Eutermes) odontomachus]H42 |--M. pelatus Hill 1942H42 `--M. percomis Hill 1942H42 Invasitermes Miller 1984M84 |--*I. inermis Miller 1984M84 `--I. insitivus (Hill 1929) [=Mirotermes insitivus, Termes insitivus]M84 Incolitermes pumilusWG91 CeratotermesA50 Megagnathotermes notandusA50 Spicotermes brevicarinatusA50 Crepititermes verruculosusA50 Hesperotermes Gay 1971M91 `--*H. infrequens (Hill 1927) [=Mirotermes infrequens]M91 Apsenterotermes Miller 1991M91 |--*A. improcerus Miller 1991M91 |--A. aspersus Miller 1991M91 |--A. declinatus Miller 1991M91 |--A. iridipennis (Gay 1956) [=Termes iridipennis]M91 `--A. stenopronos Miller 1991M91 Ekphysotermes Gay 1971M91 |--*E. kalgoorliensis (Hill 1942)M91, H42 [=Mirotermes kalgoorliensisM91] |--E. jarmuranus (Hill 1929)M91, H42 [=Mirotermes jarmuranusM91] |--E. ocellarisM91 |--E. pelatusM91 `--E. percomisM91 Hapsidotermes Miller 1991M91 |--*H. maideni (Mjöberg 1920) [=Mirotermes maideni, Termes maideni]M91 |--H. harrisi (Mjöberg 1920) [=Mirotermes harrisi, Termes harrisi; incl. M. alicensis Mjöberg 1920]M91 |--H. labellus Miller 1991M91 |--H. longius Miller 1991M91 `--M. orbus (Hill 1927) [=Mirotermes orbus, Termes orbus]M91 0--Saxatilitermes Miller 1991M91 | `--*S. saxatilis Miller 1991M91 `--Lophotermes Miller 1991M91 |--*L. pectinatus Miller 1991M91 |--L. aduncus Miller 1991M91 |--L. brevicephalus Miller 1991M91 |--L. crinitus Miller 1991M91 |--L. leptognathus Miller 1991M91 |--L. parvicornis Miller 1991M91 |--L. pusillus Miller 1991M91 |--L. quadratus (Hill 1927) [=Mirotermes quadratus, Termes quadratus]M91 `--L. septentrionalis (Hill 1927) [=Mirotermes septentrionalis, Termes septentrionalis]M91 Amphidotermes basidensA50 Eurytermes assmuthiA50 Hoplotermes amplusA50 Ahamitermes Mjöberg 1920A50, H42 |--A. hilli Nicholls 1929 [=Hamitermes (Ahamitermes) hillii]H42 |--A. nidicola Mjöberg 1920 [=Hamitermes (Ahamitermes) nidicola]H42 `--A. pumilus (Hill 1942) [=Hamitermes (Ahamitermes) pumilus]H42 Pseudocapritermes silvaticusA50 Protocapritermes Holmgren 1912M91 `--P. krisiformis (Froggatt 1898)M91 (see below for synonymy)
Protocapritermes krisiformis (Froggatt 1898)M91 [=Termes krisiformisM91, Mirotermes (Protocapritermes) krisiformisH42, T. (Eutermes) krisiformisH42]
*Type species of generic name indicated
References
[A50] Ahmad, M. 1950. The phylogeny of termite genera based on imago-worker mandibles. Bulletin of the American Museum of Natural History 95 (2): 37–86.
Bignell, D. E., H. Oskarsson, J. M. Anderson & P. Ineson. 1983. Structure, microbial associations and function of the so-called “mixed segment” of the gut in two soil-feeding termites, Procubitermes aburiensis and Cubitermes severus (Termitidae, Termitinae). Journal of Zoology 201: 445–480.
[GN54] Grassé, P.-P., & C. Noirot. 1954. Apicotermes arquieri (Isoptère): ses constructions, sa biologie. Considérations générales sur la sous-famille des Apicotermitinae nov. Annales des Sciences Naturelles—Zoologie et Biologie Animale, ser. 11, 16: 345–388.
[GE05] Grimaldi, D., & M. S. Engel. 2005. Evolution of the Insects. Cambridge University Press: New York.
[H42] Hill, G. F. 1942. Termites (Isoptera) from the Australian Region (including Australia, New Guinea and islands south of the Equator between 140°E. longitude and 170°W. longitude). Commonwealth of Australia Council for Scientific and Industrial Research: Melbourne.
[H79] Howse, P. E. 1979. The uniqueness of insect societies: Aspects of defense and integration. In: Larwood, G., & B. R. Rosen (eds) Biology and Systematics of Colonial Organisms pp. 345–374. Academic Press: London.
[IVE07] Inward, D. J. G., A. P. Vogler & P. Eggleton. 2007. A comprehensive phylogenetic analysis of termites (Isoptera) illuminates key aspects of their evolutionary biology. Molecular Phylogenetics and Evolution 44: 953–967.
[JK75] Jacobson, H. R., & D. H. Kistner. 1975. Numeric analyses of relationships of genera and species of the subtribe Termitusina (Coleoptera: Staphylinidae). Systematic Zoology 24 (2): 191–198.
[K-WK92] Korn-Wendisch, F., & H. J. Kutzner. 1992. The family Streptomycetaceae. In: Balows, A., H. G. Trüper, M. Dworkin, W. Harder & K.-H. Schleifer (eds) The Prokaryotes: A handbook on the biology of bacteria: Ecophysiology, isolation, identification, applications 2nd ed. vol. 1 pp. 921–995. Springer-Verlag: New York.
Lo, N., & P. Eggleton. 2011. Termite phylogenetics and co-cladogenesis with symbionts. In: Bignell, D. E., et al. (eds) Biology of Termites: a modern synthesis pp. 27–50. Springer.
[M84] Miller, L. R. 1984. Invasitermes, a new genus of soldierless termites from northern Australia (Isoptera: Termitidae). Journal of the Australian Entomological Society 23: 33–37.
[M91] Miller, L. R. 1991. A revision of the Termes-Capritermes branch of the Termitinae in Australia (Isoptera: Termitidae). Invertebrate Taxonomy 4: 1147–1282.
[N55] Noirot, C. 1955. Termites du centre et du sud-ouest de l’Angola récoltés par A. de Barros Machado. Diamang Publicações Culturais 27: 139–150.
[N90] Nutting, W. L. 1990. Insecta: Isoptera. In: Dindal, D. L. (ed.) Soil Biology Guide pp. 997–1032. John Wiley & Sones: New York.
Prestwich, G. D. 1984. Defense mechanisms of termites. Annual Review of Entomology 29: 201–232.
[S57] Seevers, C. H. 1957. A monograph on the termitophilous Staphylinidae (Coleoptera). Fieldiana Zoology 40: 1–334.
[SVT04] Sornnuwat, Y., C. Vongkaluang & Y. Takematsu. 2004. A systematic key to termites of Thailand. Kasetsart Journal of Natural Science 38 (3): 349–368.