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| Termitotrox icarus
Kakizoe, Liang, Myint & Maruyama, 2020
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Abstract
A new species of scarab beetle, Termitotrox icarus sp. nov., is described from central Myanmar, being the third representative of the genus Termitotrox Reichensperger, 1915 from the Indo-Chinese Subregion of the Oriental Region. The majority of the type series was collected from the walls of fungus garden chambers built in the nests of the termite Odontotermes proformosanus Ahmad, 1965. Termitotrox icarus sp. nov. can be easily distinguished from the known Termitotrox as it possesses wing-shaped trichomes on the elytra, the more elongate habitus shape in dorsal view, the basomedian section of pronotum not protruding backwards, a pair of distinct costae on the pronotal basomedian section strongly developed, a median costa on anterior pronotal margin strongly developed, the elytral striae narrower than interstriae, the lack of trichomes at the base of elytral sutural stria, and a mid-range body length of 1.5–1.9 mm. The ‘carrying behavior’ by the host termites is reported for the first time for Termitotrox and a strategy for the dispersal of flightless termitophilous scarabs is hypothesized.
Key words: Coleoptera, Aphodiinae, Termitotrogini, Blattodea, Termitidae, Macrotermitinae, new species, egg gigantism, phoresy, termite association, Indo-Chinese Subregion, Oriental Region
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| alive specimen of Termitotrox icarus sp. nov. walking on the wall of fungus garden chamber |
Termitotrox icarus sp. nov.
Diagnosis. This species is similar to T. cupido and T. venus
in having wing-shaped trichomes on the elytral base, but
it is easily distinguished from these species because of the
following combination of characters: a) the more elongate
habitus shape in dorsal view, b) the basomedian section of
pronotum not protruding backwards, c) a pair of distinct
costae on the pronotal basomedian section are strongly
developed, d) a median costa on anterior pronotal margin
is strongly developed, e) the elytral striae narrower than
interstriae, e) the lack of trichomes at the base of elytral
sutural stria, and f) a size intermediate between the two
aforementioned species (1.5–1.9 mm) vs. 1.2 mm in T. cupido and 2.4 mm in T. venus.
Etymology. In Greek mythology, Icarus was the son of
Daedalus. He is famous for having approached the sun
with wings made of feathers and wax, which melted and
gradually became smaller, thus eventually causing his
falling into the sea. The name refers to the smaller elytral
wing-shaped trichomes compared to the other known
species of the genus having wing-shaped trichomes (i.e.,
Termitotrox cupido and T. venus). Noun in apposition.
Symbiotic host. Odontotermes proformosanus Ahmad,
1965 (identifi ed by Dr. Yoko Takematsu).
Remarks. In some female specimens, we observed a single
giant egg (Figs 21 and 22). We randomly chose 20 females
and dissected them, 17 of them had one single egg while
the others did not bear any egg.
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| Carrying behavior by host termite Odontotermes proformosanus Ahmad, 1965 to Termitotrox icarus sp. nov. (observed in laboratory). |
Behavioral observations. In laboratory-based observations, we recorded multiple instances of host termite minor workers carrying T. icarus sp. nov. individuals with their mandibles (Figs 18 and 19, and S1). The beetle constantly exposed its antennae and legs and frequently moved its legs. In each instance, the carrying period was about 5 minutes. This behavior was also observed multiple times in the field. However, nutrient exchange (trophallaxis) between the termite and beetle was not observed during either fi eld or laboratory observations.
Kakizoe Showtaro, Liang Wei-Ren, Myint Khin Mar and Maruyama Munetoshi. 2020. Termitotrox icarus sp. nov. (Coleoptera: Scarabaeidae): A New Termitophilous Beetle from Myanmar with Observations of Carrying Behavior by Host Termites. Acta Entomologica Musei Nationalis Pragae. 60(2); 427-436. DOI: 10.37520/aemnp.2020.27
