Isognathotermes heghi (Sjöstedt, 1924)

Figs 36–37

Revised herein as junior synonym of I. bulbifrons .

Cubitermes heghi Sjöstedt, 1924b: 255 .

Cubitermes heghi – Sjöstedt 1926: 249, table 9 k1–k3. — Snyder 1949: 160. — Ruelle 1992: 500.

Mirotermes (Cubitermes) heghi – Emerson 1928: 511–513, fig. 56.

Cubitermes bulbifrons – Ruelle 1975: 7. — Krishna et al. 2013: 1917. — Josens & Deligne 2019: 60.

Isognathotermes bulbifrons – Hellemans et al. 2021: 233.

Junior synonym of Isognathotermes bulbifrons (Sjöstedt, 1924) .

Etymology

In the original description, Sjöstedt (1924b: 255) stated: “This species is named in honour of Mr E. Hegh, attached to the Belgian Ministry of Colonies and author of the beautiful and well-researched summary work ‘ Les Termites’ ”.

Historical review

Sjöstedt (1924b: 255) briefly described the soldier of this species under the name Cubitermes heghi . Two years later he provided a more detailed description of soldier and a first description of worker (Sjöstedt 1926: 249). He included Cubitermes heghi in his soldiers’ key of Cubitermes species (1926: 221–226) and inserted it in a “ bulbifrons -Gruppe” of species with an upwards humped soldier’s frons.

Emerson (1928: 511–513) referred to this species under the name Mirotermes (Cubitermes) heghi and provided a redescription (with figures) of the soldier; he noted that the soldiers of M. (C.) heghi and of M (C) bulbifrons were similar to each other but that the imagines were very different. However, the imago described by Emerson was misidentified and belonged to Cubitermes (now Polyspathotermes) sulcifrons, characterized by a large fontanelle.

Snyder (1949: 160) catalogued this species under the name Cubitermes heghi and housed it in the sub-family Termitinae .

Ruelle (1975: 7) considered C. bulbifrons as senior synonym of C. heghi; however, later, Ruelle (1992: 500) gave precedence to C. heghi over C. bulbifrons .

Krishna et al. (2013: 1916) housed C. bulbifrons in the sub-family Cubitermitinae . Espousing the view of Ruelle 1975 but contesting the reversal of precedence proposed by Ruelle 1992, they considered this species as the senior synonym of C. heghi .

Hellemans et al. (2021: 233) placed this species in the restored genus Isognathotermes .

One subsample has been examined (see Isognathotermes bulbifrons, DJ 0290). Krishna et al. (2013: 1917) mention that other paratype subsamples are deposited in PPRI (not examined) and IEAP; however, the material that was lent by this latter museum did not contain any Cubitermes heghi sample.

Synonymy of both species is compatible with their enteric valve morphology, as both species belong to the same finitimus valve pattern group (Josens & Deligne 2019: 42–44). Their morphology also supports synonymy. Following Ruelle (1975) and Krishna et al. (2013), I. heghi is therefore considered a junior synonym of Isognathotermes bulbifrons (Sjöstedt, 1924) .