Callirhytis rugulosa
(agamic)agamic:The agamic (AKA unisexual) generation of an oak gall wasp (cynipini) species consists of only female wasps, which do not mate before laying the eggs which become the male and females of the sexual generation (sexgen).
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The gall's range is computed from the range of all hosts that the gall occurs on. In some cases we have evidence that the gall does not occur across the full range of the hosts and we will remove these places from the range. For undescribed species we will show the expected range based on hosts plus where the galls have been observed.
Our ID Notes may contain important tips necessary for distinguishing this gall
from similar galls and/or important information about the taxonomic status of
this gall inducer.
Created Feb 4, 2026 1:47 PM UTC
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Last updated Feb 4, 2026 1:47 PM UTC
Two new species of Cynipidae
William Beutenmuller
(1911)
Andricus rugulosus, sp. nov.
Gall. — Singly or in clusters of two to about eight, on the trunks of young trees or along the stems of very young shoots of red and black oaks (Quercus rubra and Quercus velutina) late in April until early in May (8th), when the leaves begin to develop. Monothalamous. Ovate or bud-like, somewhat rough and longitudinally ribbed. Bluntly pointed at the apex. Soft, fleshy and green when fresh, often tinged with red. Hollow inside. When mature they drop to the ground, and when old they turn brown and become thin-shelled, with a large chamber inside. Length, 5-6 mm.; width, 3-3.25 mm.
Habitat. — New Jersey (Fort Lee district) ; New York (Van Courtlandt Park).
The perfect insect reaches maturity late in October, but does not emerge from the gall until April in the year following. The species is closely allied to Andricus (Trisolenia) saltatus Ashm. and punctatus Ashm. The gall exudes a honey-like liquid, which is greedily partaken by ants, and, like A. saltatus has the power of jumping, due to the contraction and sudden relaxation of the larva within.
