The Antestia Bug Complex in Africa and Asia 471
10.3.1.3 Ecological Preferences at Tree Level
Kirkpatrick (1937) reported that Antestiopsis thunbergii adults and nymphs avoided direct sunlight dur-
ing the hottest hours of the day when they usually hid within the coffee bush in the leaf cover. The
author also wrote that Antestia bugs usually were more visible in the morning and evening or during
cloudy days. Foucart and Brion (1959) reported that feeding activity of A. thunbergii ghesquierei usually
occurred between 10 a.m. and noon and between 7 p.m. and 8 p.m. in Rwanda and Burundi. By contrast,
the long flights of adults, involved in the process of new plantation colonization, usually occurred in the
warmer hours of the day.
A recent study in Rwanda described the distribution of Antestia bug adults on different parts of the
coffee tree during the day. The results presented in Figure 10.2 showed that the bugs spent more time
on green berries than on other parts of the tree, and that they declined in number from early morning
to mid-day, then increased again in the afternoon. The numbers of bugs on leaves and stems were more
variable, although they varied with a similar trend over the day. The number of bugs on the ground was
negligible (N. D. T. M. Rukazambuga, unpublished data).
Most authors agreed that bushy coffee trees sheltered more Antestia bugs than open ones (e.g.,
Le Pelley 1968). In line with this observation, coffee pruning is a common recommendation for Antestia
bug control. Although Antestia bug adults and nymphs are mobile insects, their movements between or
within coffee trees are limited and presumably allow them to avoid large variations in temperature and
moisture.
10.3.2 Feeding Habits
10.3.2.1 Host Plants
Antestia bugs have been found on a wide range of plants from different botanic families. However,
feeding and/or breeding have been observed for a limited number of them, mainly from the Rubiaceae.
According to old insect collections in Eastern Africa, Antestia bugs, most likely Antestiopsis thunbergii,
were found on Poaceae such as finger millet (Eleusine coracana Gaertn.), sorghum (Sorghum spp.), and
maize (Zea mays L.); on Musaceae such as banana (Musa); on Euphorbiaceae, such as the castor oil plant
(Ricinus communis L.); and on Malvaceae such as okra (Abelmoschus esculentus (L.) Moench.); Antestia
bugs also were found on fruits of Annonaceae, and on flowers of Gliricidia maculata Kunth (Fabaceae),
Symphonia globulifera L. (Clusiaceae) and Bridelia micrantha (Hochst) Baill. (Phyllanthaceae)
(Anderson 1919, Wilkinson 1924). In addition, eggs of Antestia bugs have been found on unidentified
16
14
12
10Bug per tree
8
6
4
2
0
7-8am 8-9am 9-10am 10-11am 11 am-noon 3-4pm 4-5pm
Time in the dayBugs on ground Bugs on stem Bugs on leaves Bugs on berriesFIGURE 10.2 Mean number of Antestia bugs per tree observed on coffee berries, leaves, and stems and on the ground at
various times of the day, from a sample of three coffee trees sheltering at least 12 Antestia bugs, in Rwanda (N. D. T. M.
Rukazambuga, unpublished data).