Phylloxerid
Guides
Parapergandea
Parapergandea is a genus of phylloxerids (family Phylloxeridae) in the order Hemiptera, established by Börner in 1930. It is currently treated as a synonym of Phylloxera Boyer de Fonscolombe, 1834. The genus was erected to accommodate species resembling Phylloxera but with distinct morphological features, though subsequent taxonomic revisions have subsumed these taxa under Phylloxera. Records attributed to Parapergandea have been reported from Scandinavia (Denmark, Norway, Sweden) and the northeastern United States (Vermont).
Parapergandea caryaevenae
Parapergandea caryaevenae is a species of phylloxerid insect originally described by Fitch in 1856. It is currently recognized as a synonym of Phylloxera caryaevenae. The species belongs to the family Phylloxeridae, a group of small, sap-feeding insects closely related to aphids.
Phylloxera caryaeavellana
hickory phylloxeran, hickory phylloxera
Phylloxera caryaeavellana is a small, gall-forming insect in the family Phylloxeridae that infests hickory trees (Carya species). The species causes distinctive swollen, globular galls to form on leaves, petioles, and leaf veins during spring growth. It is closely related to aphids and shares their piercing-sucking mouthpart morphology. The insect has a complex life cycle involving multiple generations and winged dispersal forms. Unlike the economically devastating grape phylloxera (Daktulosphaira vitifoliae), this species is primarily a curiosity rather than a significant agricultural pest, causing minimal lasting damage to healthy host trees.
Phylloxera notabilis
Pecan Leaf Phylloxera
Phylloxera notabilis is a gall-forming insect in the family Phylloxeridae, closely related to aphids. It is a significant pest of pecan trees (Carya illinoinensis), forming characteristic galls on leaf tissue. The species has host-associated populations on both pecan and water hickory (Carya aquatica), with documented differences in bacterial diversity between these populations. Unlike the more destructive pecan phylloxera (Phylloxera devastatrix), which attacks shoots and nuts, P. notabilis primarily damages leaves and may cause defoliation in heavy infestations.
Phylloxera querceti
Phylloxera querceti is a gall-forming insect in the family Phylloxeridae, closely related to aphids. The species induces abnormal plant growths (galls) on oak species (Quercus), within which it develops and feeds. Like other phylloxerans, it has a complex life cycle involving both sexual and parthenogenetic generations, with overwintering eggs hatching in spring to produce fundatrices that initiate gall formation. The specific host associations and gall morphology distinguish it from congeners such as the economically significant grape phylloxera (Daktulosphaira vitifoliae).
Phylloxerina
Phylloxerina is a genus of phylloxerids—small, sap-sucking true bugs in the family Phylloxeridae. These insects are closely related to aphids and are known for inducing distinctive leaf galls on host plants. The genus includes species such as Phylloxerina nyssae, which forms crescent-shaped galls on black tupelo (Nyssa sylvatica). Phylloxerids are morphologically unusual among Sternorrhyncha, with wax-covered bodies and complex life cycles involving both gall-dwelling and bark-dwelling generations. The genus is native to northern North America.
Phylloxerina nyssae
Phylloxerina nyssae is a minute gall-forming phylloxerid that induces distinctive yellowish-white crescent-shaped galls along the leaf margins of Nyssa sylvatica (black tupelo or sour gum). Adults are approximately 1 mm in length with sucking mouthparts positioned between the first pair of legs. The species reproduces asexually within galls, with females producing dozens of pill-shaped translucent eggs. Overwintering occurs as wax-covered individuals concealed in bark crevices and craggy trunk folds. While the gall formation causes cosmetic damage to foliage, the tree remains otherwise healthy.
Pineus similis
Ragged Spruce Gall Adelgid
Pineus similis is a gall-forming adelgid that induces galls on spruce trees (Picea spp.). Originally described as Chermes similis by Gillette in 1907 from blue spruce in Colorado, it was later transferred to genus Pineus by Annand. The species produces winged females that emerge from galls and settle on spruce hosts, with documented preference for white spruce. Wingless females bearing egg clusters occur within galls. It has been recorded on multiple spruce species across North America and has doubtful or rare records in Europe.