VOL 54, NO. 1, JANUARY 1978 
69 
mali and M. fasciatum and by Farris (1965, Proc. Entomol. Soc. B.C., 62:30-33) for M. scutel- 
lare. 
!n November of 1970, live specimens of M. dentiger were removed from a Quercus agri- 
fola Nee collected in the Castle Rock State Park, Santa Clara County. The host tree was 
leafless and appeared to have recently died. The gallery systems contained numerous 
adult beetles which appeared inactive in their brood niches. Upon microscopic study, 
these tunnels and niches appeared to lack active fungal growth and did not yield A. 
brunnea when isolations were attempted. Within dissected mycangia only a few thick 
wall fungal cells were observed. Only a single successful isolation of A. brunnea was ob¬ 
tained from dissected mycangia of eight female adult beetles. In July of 1971 beetles were 
recollected from dead 0. agrifola and 0. lobata Nee at the Castle Rock site and from Q. 
agrifola near Camp Saratoga, Santa Clara County. These galleries contained active mono¬ 
gamous pairs of adult beetles; eggs in small cradles in lateral walls of the tunnels; and lar¬ 
vae, pupae, and teneral adults developing within larval niches.The parental pair of beetles 
were continuing to lengthen the tunnels system in the host. A thin palisade of fungal 
growth lined the tunnels and larval niches. Larvae were actively feeding on this fungal 
layer. Seven isolations from larval niches all yielded cultures of A. brunnea. The fungus 
taken from the mycangia appeared to be rapidly budding. All eight isolations attempts 
yielded cultures of A. brunnea. Other observations of the biology of M. dentiger were 
similar to those made by Doane and Guilliland (Ibid.). The larger oak ambrosia beetle M. 
scutellare was also collected from these same host tress and also yielded A. brunnea from 
their tunnels and mycangia. — RICHARD A. ROEPER and JOHN R. J. FRENCH, 
Departments of Botany and Entomology, Oregon State University, Corvallis, 97331. 
SCIENTIFIC NOTE 
Cicada (Diceroprocta apache (Davis)) mortality by feeding on Nerium oleander. In mid- 
July 1977, there was a strong emergence of cicadas, Diceroprocta apache, in the vicinity of 
Tacna, Yuma County, southwestern Arizona. In this desert habitat the adult cicadas were 
feeding on the sap of many species of desert shrubs, including Prosopis juliflora, Cercidium 
floridum, Cercidium microphyllum, and Acacia gregii. It was commonplace to flush two to fif¬ 
teen adult cicadas from a shrub of one of these species. In the grounds of a motel and 
several private gardens in Tacna, Nerium oleander had been planted as an ornamental tree. 
Cicadas were often observed feeding on the twigs of these trees. The plants ranged from 
2 to 3 m in height and were of approximately the same size as native desert shrubs. 
Oleander is native to old world arid areas such as the Mediterranean. It is in the family 
Apocynaceae and it is widely reputed to be poisonous to livestock when fed upon. If the 
foliage is broken, it produces a bitter white latex. Characteristically, oleander bushes are 
very free from herbivore damage, no matter where they are planted. Under 10 separate 
oleander bushes in central Tacna, I counted 28, 12, 15, 17, 3, 22, 9, 7, 16, and 23 dead 
cicadas. Under one bush, I know that at least 6 died during the night as they fell on top of 
my car which had been parked underneath the bush. Both sexes were among the corpses. 
No dead cicadas were encountered under a total of 17 shrubs of other species, all of 
which had cicadas feeding on them in central Tacna. The dead cicadas were in various 
stages of decomposition, which suggests that they had died over a period of several days. 
I interpret these observations to mean that oleander is a novel food plant in the habitat 
of these cicadas, a food plant with which they have not evolved the ability to avoid. In 
other words, there may well be plants which adult D. apache do not feed on in south- 
The Pan-Pacific Entomologist 54:69-70 January 1978 
