RECLASSIFICATION OF SUBFAMILY AGRYPNINAE 101 
ELASMOSOMUS Schwarz 
Elasmosomus Schwarz, 1902b: 212. Type-species: Elasmosomus fasciculatus Schwarz, by 
subsequent designation (Hyslop, 1921 : 643). 
GENERIC DIAGNOSIS. Each claw with a group of setae near the base (Text-fig. 11). Tibial 
spurs absent (Text-fig. 10). Mesepisternum does not form part of the margin of the mesocoxal 
cavity; mesepimeron forms part of the margin of the mesocoxal cavity (Text-fig. 3). Second 
and third antennal segments not subequal, the third resembles the fourth and following 
segments. Antennal groove shallow and short, not extending beyond the anterior half of the 
prosternopleural suture. Body clothed with narrow scales. Prothorax cylindrical, elongate, 
not constricted behind the anterior angles. Lateral carina present, pronotal tubercles present 
or absent. Propleurae and metasternum without well defined grooves for the reception of the 
anterior and middle tarsi. Scutellum simple, without longitudinal carinae. Third and fourth 
tarsal segments with ventral lobes. 
RANGE OF VARIATION FOUND WITHIN THE GENUS. All the species known to 
me bear a strong resemblance to one another. Examination of long series of 
specimens suggests that there may be a wide range of variation in the length of 
individual specimens belonging to the same species. 
HISTORY OF THE GENUS. The genus was established for the African species 
attributed to the genus Dzlobitarsus, which originally included only South American 
species. 
Schwarz originally included the genus in the tribe Dicrepidini but four years 
later (1906 : 15) he transferred it to the Agrypnini [sic, see p. 4] without com- 
ment. Fleutiaux (1941), who on a previous occasion (1919 : I1) did not recognize 
Elasmosomus as a valid genus, preferring to use Dilobitarsus for both African and 
South American species, treated them as two entirely distinct genera. He included 
Dilobitarsus in the Agrypnitae [sic, see p. 4] but excluded Elasmosomus, basing 
his action on the fact that the structure of the head of Elasmosomus species bears 
a certain resemblance to that found in Anaspasis (S. America) and Protelater 
(New Zealand). Examination of the type-species of these two genera has shown 
that the resemblance is only superficial. Both genera differ from Elasmosomus 
in that they possess tibial spurs and lack setae at the base of the claws. Further 
studies may show that Elasmosomus should not be included in the Agrypninae 
but at the present time there is, in my opinion, no convincing reason for excluding 
the genus from the subfamily. 
The main difference between Elasmosomus and Dilobitarsus, apart from the 
distribution, is that in the former the antennal grooves are distinctly shorter 
and shallower than in the latter. Only the characteristic cylindrical shape of 
the body, the tubercles on the head and the fact that the frons is not margined 
anteriorly distinguishes Elasmosomus from Hemicleus. However as no inter- 
mediate forms are known and there is no difficulty in assigning species to the 
appropriate genus, the two genera have been retained in the present work. 
DistripuTion. Africa and Madagascar. 
BIoLoGy AND HABITS. Nothing has been published on the life history and 
habits of Elasmosomus species. A few specimens known to me bear labels indicating 
that they were found on trees or in tree stumps. 
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