Please check the following link.

https://books.google.co.in/books?id=wmSc-2KDmZ4C&pg=PA113&lpg=PA113&dq=belostomatidae+in+Madagascar&source=bl&ots=6sIqi__CaE&sig=ZLPCoseXUX80QnNSraUPgP1i32o&hl=en&sa=X&ved=0ahUKEwjWwYPX7PzQAhVGOo8KHepHDgU4ChDoAQggMAI#v=onepage&q=belostomatidae%20in%20Madagascar&f=false

I would suggest Lethocerus sp.

Dear Ton van Haaren

This  Belostomatid insect belonging to genus Lethocerus

With my best wishes

Dag Ton,

Heb je iets aan deze literatuurgegevens?

P. J. Perez-Goodwyn (2006). "Taxonomic revision of the subfamily Lethocerinae Lauck & Menke (Heteroptera: Belostomatidae)". Stuttgarter Beiträge zur Naturkunde, Serie A (Biologie). 695: 1–71. 

D. R. Lauck (1962). "A monograph of the genus Belostoma (Hemiptera), Part I. Introduction and B. Dentatum and Subspinosum groups". Bulletin of the Chicago Academy of Sciences. 11 (3): 34–81. 

D. R. Lauck (1963). "A monograph of the genus Belostoma (Hemiptera), Part II. B. Aurivillianum, Testaceopallidium, Dilatatum, and Discretum groups". Bulletin of the Chicago Academy of Sciences. 11 (4): 82–101. 

D. R. Lauck (1964). "A monograph of the genus Belostoma (Hemiptera, Part III. B. Triangulum, Bergi, Minor, Bifoveolatum, and Flumineum groups". Bulletin of the Chicago Academy of Sciences. 11 (5): 102–154. 

A. S. Menke (1960). "A taxonomic study of the genus Abedus Stål (Hemiptera, Belostomatidae)". University of California Publications in Entomology. 16 (8): 393–440. 

R. L. Smith (1974). "Life history of Abedus herberti in Central Arizona" (PDF). Psyche. 81 (2): 272–283. doi:10.1155/1974/83959. 

R. T. Schuh & J. A. Slater (1995). "True Bugs of the World (Hemiptera:Heteroptera): Classification and Natural History". Cornell University Press.

Misschien nog beter: contact op nemen met

Hawaii Biological Survey Staff

Dan A. Polhemus, Ph.D.

Research Associate - Entomology

phone: 808-847-8204

fax: 808-847-8252

email: bugman[at]bishopmuseum[dot] org 

of

Nico Nieser

Beiden lijken me nogal wat ervaring te hebben opgebouwd over wantsen in die regio.

Zij hebben dus wellicht een nog betere kijk op hedendaagse info!

Groetjes

Thierry