ETHIOPIAN NASUTITERMITINAE n 



includes species which differ markedly, and show resemblances to genera on different 

 subsidiary divisions of the " Procomitermes branch ". This suggests a polyphyletic 

 origin for the genus, which needs to be clarified by a study of all the species. In 

 the Ethiopian Region, N . latifrons, N . schoutedeni and N. lujae appear to be derived 

 from ancestors close to the genera Hirtitermes and Havilanditermes as suggested by 

 Ahmad, whereas N. kempae and N. elegant uhts show resemblances to the Neo- 

 tropical genera Diversitermes and Parvitermes. Both A', latifrons and A', kempae 

 exhibit traces of " instar " polymorphism in soldier and worker. 



Leptomyxotermes doriae from West Africa appears to be most closely related to the 

 Hospilalitermes-Lacessititermes group of constricted-headed genera, as is its relative 

 Grallalotermes africanus from East Africa. Leptomyxotermes also shows traces of 

 soldier polymorphism which have been lost in Grallatotermes. 



The genera F idler itermes and Rhadinotermes, although they have constricted- 

 headed soldiers, are not closely related to Leptomyxotermes and Grallatotermes. 

 Their affinities are instead to another subsidiary branch of mainly Neotropical 

 genera, including Velocitermes, Temtirostritermes, and Diversitermes. In Fidler- 

 itermes, F. coatoni has distinctly dimorphic soldiers whereas in F. contractus and 

 /• . tcnebricus there are only vestiges of polymorphism, and F. mallyi has a single 

 soldier form, as does Rhadinotermes. The importance of soldier polymorphism as 

 a character varies greatly. In some genera it appears to be on the point of dis- 

 appearance and varies between species, whereas in others its presence is well marked, 

 and closely related monomorphic forms must be given separate generic status. Such 

 is the case with Trinervitcrmes, which is always polymorphic though showing inter- 

 gradations from true dimorphism to near " instar " polymorphism, and Baucalio- 

 termes which is truly monomorphic. These genera, and Mycterotermes, also appear 

 to be most closely related to the 1'enuirostritermes Diversitermes branch, which 

 would therefore seem to be the most important subdivision of the " Procomitermes 

 branch " of the subfamily. 



The collection of new material of humus-feeding species on the " Paracornitermes 

 branch " has permitted a more detailed assessment of their relationships. Futcrm- 

 ellus is the most primitive genus of the Ethiopian Region. 



In some respects, such as the distinctly trilobed soldier labrum, and the " imago- 

 worker " mandibles with a sinuate cutting edge between left first and third mar- 

 ginals, and the right molar plate with vestigial ridges, it appears to be more primitive 

 than the Neotropical Angularitermes, in spite of the long points on the soldier 

 mandibles of the latter genus. The relationship of the genera are discussed in detail 

 under their own generic headings. 



DISTRIBUT I ()X 



Representatives of the subfamily are to be found in every vegetation zone from 

 the depths of the tropical rain forests and mangrove swamps to the fringes of the 

 deserts both North and South of the Equator. 



In the humid rain forest areas of West Africa and the Congo, N asutitermes is the 

 dominant genus with ten species feeding mainly on dead wood of all kinds. 



