Rasahus albomaculatus, the White-Spotted Corsair

Though the Hemiptera began their long evolutionary history as plant-feeders, many of their subgroups later switched to a predatory lifestyle, their suctorial mouthparts being just as suited for stabbing flesh as vegetation. Among the most successful of the predatory bugs where the assassin bugs of the family Reduviidae.

Image copyright Jacob Gorneau.

This is Rasahus albomaculatus, a widespread assassin of the Neotropical region, found from Mexico to Argentina (Coscaron 1983). Though not one of the largest members of its genus, R. albomaculatus is a decent-sized bug, growing close to an inch in length. Rasahus is a genus of the reduviid subfamily Peiratinae, commonly known as corsairs for their fearsome aspect. Features distinguishing Rasahus from other genera of corsairs include their large eyes, a deep grove across the head in front of the ocelli, long procoxae, and well-developed spongy pads on the fore- and mid-tibiae. Rasahus albomaculatus is distinguished from other species of the genus by its colour pattern. The body is mostly black with white patterning on the wings. Stripes along the top of the wing and across the mid-length form a crude H-shape when the wings are closed, with separate spots towards the base of the wing and towards the tip. Other noteworthy features include a lack of granulation on the pronotum, and a rounded apex to the scutellum (Swanson 2018).

Corsairs are mostly predators of other insects and not often dangerous to humans (though their bite is supposed to be very painful). Indeed, they may be beneficial to humans as among their prey are believed to be other reduviids of the subfamily Triatominae, the blood-sucking "kissing bugs" that spread Chagas disease (contrary to the Wikipedia page on the western corsair R. thoracicus, corsairs do not spread Chagas themselves). Rasahus albomaculatus may provide its vertebrate co-habitants with far more comfortable living conditions.

REFERENCES

Coscarón, M. del C. 1983. Revision del genero Rasahus (Insecta, Heteroptera, Reduviidae). Revista del Museo de La Plata (nueva serie) (Zoologia) 13: 75–138.

Swanson, D. R. 2018. Three new species of Rasahus, with clarification on the identities of three other Neotropical corsairs (Heteroptera: Reduviidae: Peiratinae). Zootaxa 4471 (3): 446–472.