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Species Pachypsylla celtidisvesicula - Hackberry Blister Gall Psyllid

hackberry blister galls, Pachypsylla celtidisvesiculum - Pachypsylla celtidisvesicula Hackberry gall - Pachypsylla celtidisvesicula Pachypsylla celtidisvesicula - male Male, Hackberry Blister Gall Psyllid? - Pachypsylla celtidisvesicula Male, Hackberry Blister Gall Psyllid? - Pachypsylla celtidisvesicula Male, Hackberry Blister Gall Psyllid? - Pachypsylla celtidisvesicula Male, Hackberry Blister Gall Psyllid? - Pachypsylla celtidisvesicula very small - Pachypsylla celtidisvesicula
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hemiptera (True Bugs, Cicadas, Hoppers, Aphids and Allies)
Suborder Sternorrhyncha (Plant-parasitic Hemipterans)
Superfamily Psylloidea
Family Aphalaridae
Subfamily Pachypsyllinae
Genus Pachypsylla (Hackberry Psyllids)
No Taxon (celtidismamma complex)
Species celtidisvesicula (Hackberry Blister Gall Psyllid)
Synonyms and other taxonomic changes
Pachypsylla vesiculum Riley, 1890
Explanation of Names
Pachypsylla celtidisvesicula Riley, 1890
2-2.5mm(1), but a series of adults reared from blister galls by Michael Palmer in Oklahoma measured just over 3mm in length
Galls are blister-like, most prominent on the upper surface of the leaf(1). Adults are similar to P. celtidismamma but are smaller and with wing pattern usually more diffuse. Tuthill notes that the sudden narrowing midway of the ventral valve of the female genital segment is the most reliable way to distinguish the two species(1). See also Zack Falin's comment below.
Widespread in North America (range map)(2)
Hackberry (Ulmaceae: Celtis spp.) including C. occidentalis, C. reticulata, C. tenuifolia, & C. laevigata (3)
Life Cycle
Overwinters as adults(1)
Zack Falin on P. celtidismamma and P. celtidisvesicula: "While the galls may be easy to distinguish, these two species are a real pain. A lot has been published on these, but here are my observations: given Crawford's (1914) key, I'm calling the individuals 2.5 mm and smaller P. celtidisvesicula and those larger than 3.0 mm P. celtidismamma. The individuals in between (about a third of my specimens)- I don't know! The smaller ones tend to be darker with less pronounced maculations on the head and thorax with slightly more consistent wing patterns. The larger ones tend to have more pronounced maculations on the body and have quite variable wing patterns. They both seem to occur in the same places at the same time, so take this with a grain of salt. There are a number of additional "valid" species (see Thomas, B. 2011. The authority and types for the hackberry gall psyllid... Ent. News 122(3): 279-287) that probably fall into this continuum. People are obviously interested in the genetics of these things- that's likely the only way to sort them all out for sure..."
See Also
P. celtidismamma
Works Cited
1.The psyllids of America North of Mexico: (Psyllidae: Homoptera) (Subfamilies Psyllinae and Triozinae)
Tuthill, L.D. . 1943. Iowa State College Journal of Science 17: 443-660.
2.Mallory C. (2014-) Psyllids of North America
3.Biosystematics of hackberry psyllids (Pachypsylla) and the evolution of gall and lerp formation in psyllids
Yang, M.-M. & C. Mitter. 1993. The Ecology and Evolution of Gall-forming Insects. United States Dept. of Agriculture.