TWO NEW GENERA OF SOUTH AMERICAN 
COCKROACHES SUPERFICIALLY RESEMBLING 
LOBOPTERA, WITH NOTES ON BIONOMICS 
(DICTYOPTERA, BLATTARIA, BLATTELLIDAE) . 
By Ashley B. Gurney* and Louis M. Roth** 
All cockroaches initially extrude the ootheca with the keel or the 
micorpylar ends of the eggs facing dorsally, but some species rotate 
the egg case before depositing it (Roth and Willis, 1954, 1958). 
According to McKittrick (1964), one of the important characters 
for separating the Plectopterinae from the Blattellinae (both are in 
the Blattellidae) is the position in which the ootheca is carried just 
before it is deposited by the female. In the Plectopterinae, the keel 
of the egg case remains upright until deposition; in the Blattellinae, 
the ootheca is rotated so the keel and micropylar ends of the eggs face 
laterally, behavior characteristic of the Ectobiinae and Nyctiborinae 
(Blattellidae) as well as of all the Blaberidae ( ovoviviparous and 
viviparous species). The new genera here described were recognized 
as a result of studies stimulated by observing the lack of rotation 
by a species which formerly had been assumed to be one of the 
Blattellinae. Therefore, in addition to presenting descriptions and 
biological notes, this paper provides an application of the higher cate- 
gories in the classification of McKittrick (1964). 
On June 11, 1965, one of us (L.M.R.) received some living 
specimens of Loboptera thaxteri Hebard from Buenos Aires, Argen- 
tina. 1 When we found that the females of thaxteri do not rotate the 
ootheca before its deposition, we investigated the taxonomic position 
of Loboptera Brunner. McKittrick (1964) had reported the rota- 
tion of the ootheca by Lobopterella dimidiatipes (Bolivar), 2 and as 
a result of this and other observations she placed it in the Blattelli- 
nae. [ Loboptera decipiens (Germar) also rotates its ootheca before 
deposition (Lefeuvre, 1959; Roth, unpublished observations).] We 
^Entomology Research Division, Agr. Res. Serv., U. S Department of 
Agriculture, Washington, D. C. 
**Pioneering Research Division, U. S. Army Natick Laboratories, Natick, 
Massachusetts. 
Manuscript received by the editor September 21, 1966. 
The species has been cultured easily on Purina laboratory chow. How- 
ever, individuals of thaxteri were heavily parasitized by the fungus Herpo- 
myces lobopterae Thaxter. 
‘Tor many years authors referred dimidiatipes to Loboptera, and Mc- 
Kittrick did so. Princis (1957) based the genus Lobopterella upon it. 
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