Biology, images, analysis, design...
|"It has long been an axiom of mine that the little things are infinitely the most important" |
Red-stained hickory aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
All adult viviparae of Protopterocallis gigantea are alate. Alatae (see pictures below) are broad-bodied, with a dull yellow abdomen and irregular streaks of orange or red on the mid-dorsum. The dorsal abdominal tubercles are brown-tipped and the forewing veins, especially Cu1b, are narrowly bordered with dark brown. The prothorax has two anterior tubercles and three to five posterior plus one on each posterior angle (cf. Protopterocallis quadrata, which has only 2 posterior hair-bearing tubercles on its prothorax; and cf. Pterocallis pergandei, which has 6-7 posterior tubercles on the prothorax). The mesothorax has 10-16 small tubercles, and the metathorax two to five large tubercles medially, as high as the ones on prothorax, plus 2 smaller ones. The abdomen has many rough tubercles dorsally, with much the largest on tergites I-III, crowded together on common bases and terminated by thick hairs. Some of spinal hairs on abdominal tergites I-III are neotenic (= resembling the nymphal hairs) being as long as or longer than the processes from which they arise, much longer than the hairs on the pronotum, and expanded at the tips (cf. Protopterocallis fumipennella, which has the spinal hairs on tergites I-III all shorter than the processes from which they arise, and similar in size to hairs on the pronotum).
Note: We can be fairly confident that the first two pictures below represent Protopterocallis gigantea (and not Protopterocallis fumipennella) as the common tubercular bases and long spinal hairs diagnostic for Protopterocallis gigantea are clearly visible in the lateral views. We cannot be so certain for the alate pictured third below, as the tubercles and hairs are not visible in a dorsal view.
Images above copyright John Morgan under a Creative Commons Attribution 3.0 License.
The siphunculi are poriform (=pore-shaped) on round swellings comparable in size to a marginal tubercle. The anal plate is bilobed, indented over half its length, with parallel sides. The cauda is broadly knobbed. Both the anal plate and cauda bear sharp hairs, the greatest of which is longer than the caudal width. The body length of adult Protopterocallis gigantea viviparae is 2.5-3.0 mm. Immatures (not pictured) are translucent with two internal red areas across the middle, overlaid by dusky tubercles.
Image above copyright VCharny under a Creative Commons Attribution 3.0 License.
Protopterocallis gigantea is monoecious holocyclic on several hickory (Carya) species, but has not been recorded on pecan (Carya illinoinensis). Theis aphids feed on the upper leaf surfaces, usually along mid-ribs of basal leaflets. Oviparae and males occur in October. It is found in eastern states of USA such as Maryland and Georgia.
Other aphids on the same host
Blackman records Protopterocallis gigantea on only 1 species of hickory (Carya tomentosa), but Bissell (1978) adds 3 more hickory species (Carya glabra, Carya pallida, Carya ovalis).