Humutermes, 2016

Bourguignon, Thomas, Scheffrahn, Rudolf H., Nagy, Zoltán Tamás, Sonet, Gontran, Host, Benoît & Roisin, Yves, 2016, Towards a revision of the Neotropical soldierless termites (Isoptera: Termitidae): redescription of the genus Grigiotermes Mathews and description of five new genera, Zoological Journal of the Linnean Society 176 (1), pp. 15-35 : 20-22

HUMUTERMES BOURGUIGNON & ROISIN GEN. NOV.

( FIGS 3A–E , 7C–D , 8C , 9C–D , 10 , 11 ; TABLES 4, 5)

Type species: Humutermes krishnai Bourguignon and Roisin , described below.

Description

Worker: Very small- to small-sized, head width between 0.49 and 0.62 mm. Head whitish, fully covered by over 100 small setae. Fontanelle almost indistinct. Fore tibia enlarged near middle. Digestive tract as in Figure 8C , closely resembling Anoplotermes sensu stricto. Mesenteron overlapping with proctodeum to form a distinct, elongated mixed segment. Mesenteric part of mixed segment on internal side apically inflated into a whitish, spherical diverticulum. Enteric valve inserted into an extension of the paunch, composed of six sclerotized pads with well-developed sclerotized armature.

Imago: Eyes and ocelli of medium size. Fontanelle of medium size, appearing as an elongated white dot located between eyes. Pronotum semicircular from above, covered by hundreds of small bristles and several dozen long bristles. Posterior margins of meso- and metanotum slightly emarginated, with rounded angles.

Diagnosis

Humutermes workers have an elongated mixed segment with a whitish, spherical mesenteric diverticulum. These features distinguish them from other South American soldierless termites, except for Anoplotermes sensu stricto. The overall appearance of the workers is very similar to Anoplotermes sensu stricto, with which the genus may form a monophyletic group, but the molecular phylogenetic tree is not sufficiently resolved to support this. The genus mainly differs from Anoplotermes sensu stricto by the shape of its enteric valve, composed of six pads, each with ten to 20 long spines protruding into the paunch. Imagos differ from Anoplotermes sensu stricto by their larger, more elongated fontanelle.

Etymology

We named this genus ‘ Humutermes ’ to refer to its diet, humus.

Figures

Figure 3. Worker. Humutermes krishnai sp. nov.: A, head; B, mandibles; C, foreleg; E, enteric valve (spread on slide). Worker. Humutermes noiroti sp. nov.: D, enteric valve (spread on slide).

Figure 7. Worker enteric valve armature, depicted by confocal microscopy. A, Grigiotermes hageni comb. nov.; B, Amplucrutermes inflatus sp. nov.; C, Humutermes krishnai sp. nov.; D, Humutermes noiroti sp. nov.; E, Hydrecotermes arienesho sp. nov.; F, Hydrecotermes kawaii sp. nov.; G, Patawatermes turricola comb. nov.; H, Patawatermes nigripunctatus comb. nov.; I, Rubeotermes jheringi comb. nov. (G, I, reproduced with the permission of Host et al., 2014).

Figure 8. Worker digestive tracts. A, Grigiotermes hageni comb. nov.; B, Amplucrutermes inflatus sp. nov.; C, Humutermes krishnai sp. nov.; D, Hydrecotermes arienesho sp. nov.; E, Patawatermes nigripunctatus comb. nov.; F, Rubeotermes jheringi comb. nov.. From left to right: dorsal, right, ventral, and left views.

Figure 9. Head, pronotum, mesonotum, and metanotum of alates. A, B, Grigiotermes hageni comb. nov.; C, D, Humutermes krishnai sp. nov.; E, F, Hydrecotermes arienesho sp. nov.; G, H, Hydrecotermes kawaii sp. nov.; I, J, Patawatermes turricola comb. nov.; K, L, Patawatermes nigripunctatus comb. nov.; M, N, Rubeotermes jheringi comb. nov. Scale bars = 1 mm.

Figure 10. Distribution maps of samples examined in this study.

Figure 11. Majority rule consensus phylogenetic tree including 13 focal species constructed by Bayesian inference. Numbers on branches are posterior probabilities. Species from South America are in blue font. The scale bar represents the number of mutation per site.