Pachypsylla celtidisinteneris

Gall: Occurring as Inconspicuous blisterlike elevations of the bark on younger stems of hackberry. They are monothalmic and the psyllld cells occur Just beneath the bark.

Range: Texas. P. celtldisinteneris has been previously reported from Iowa, Illinois, Kansas and Ohio.

Pachypsylla celtidisinteneris

galls oblong-oval in shape on one side of the twig, monothalamous

Pachypsylla c. inteneris, n. sp.

Pachypsylla ungulata Caldwell 1938

Celtis occidentalis, tenuifolia, laevigata, reticulata

Galls oblong-oval, and are located in the twig or base of the larger limbs, just beneath the bark

Reported from central and eastern US

Pachypsylla celtidisinteneris Mally, 1894

Pachypsylla c.-inteneris Mally, 1894. Proc. Iowa Acad. Sci. 1:138.
Pachypsylla inteneris[sic]: Crawford, 1914. USDA Bull. 83:113.
Pachypsylla ungulata Caldwell, 1938. Ohio Biol. Surv. Bull. 34:255. [synonymized by Tuthill 1943:541].
Pachypsylla celtidis-inteneris: Tuthill, 1943. Iowa St. Coll. J. Sci. 17:540.
Pachypsylla celtidisinteneris: Riemann, 1966 [emendation]. Ann. Entomol.Soc. Am. 59:1089.

Pachypsylla celtidis-inteneris

Pachypsylla inteneris
Pachypsylla ungulata

The adults emerge in the spring from the galls which are located beneath the bark on the twigs or bases of the larger limbs.

Range: IO, IL, OH

Pachypsylla sp. (gemma? see next) Figure 4

This gall is a lateral, oval swelling of the stem, generally found near or involving the nodal region. 5-7 mm. long, 2.5-3.5 mm. wide. Color and surface texture that of the normal bark. Predominately monothalamous ; confluent cases occur forming a two-chambered and even a three-chambered gall. Very common on the terminal twigs of the hackberry. Remnants of old galls can be made out on stems 5-10 years old. The galls are commonly torn open by birds to obtain the soft insects within, which spend the winter in the galls. One of these nymphs is shown on the gall (PI. XIX, Fig. 3).

It is not definitely known whether the imagoes from this gall and those from the next, P. gemma, are identical. The nymphs appear to be identical. The galls, however, are distinct, a difference, however, which may be referable to the plant part affected rather than to any specific behavior on the part of the insects respectively. This matter will be explained after P. gemma has been described.

This gall started in a similar manner to that of P. vesiculum, by the larva inducing a cone of tissue to grow over it, burying it in the superficial layer of the young stem. This minute cone early becomes obliterated.

Pachypsylla celtidisinteneris Mally, 1894
Diagnosis. Galls are formed under the bark (Tuthill 1943).
Distribution. USA: IL, KS, OH (Hodkinson 1988).
Host plants. Celtis sp. (Cannabaceae).