Aulacidea harringtoni (Ashmead, 1887)

Nomenclature: Aulax harringtoni Ashmead, 1887 | Aulax bicolor Gillette, 1891 | Aulax mulgediicolaAshmead, 1896 | Aulax cavicola Ashmead, 1896

Feeds on: Induces galls on Lactuca floridana L.

Distribution: United States: Connecticut, District of Columbia, Illinois, Massachusetts,Missouri, North Carolina, New Jersey, New York, Oklahoma; Canada: Ontario

Aulacidea harringtoni

HL Viereck "could see no difference between the type, captured at Ottawa, and paratypes of mulgegiicola "reared from cells in the pith of Lactuca villosa [floridana].

[Photo caption]

350. On Lactuca canadensis. Adults emerged the first week in June (Chi).

Aulax bicolor n. sp.

Described from two females taken in the field.

Aulax mulgediicola, new species.

The galls of this species consists simply of a thin-shelled larval cell, embedded in the pith of a common plant, Mulgidium acuminatum; usually there are numerous cells crowded together side by side in the pith, and externally the stem or stalk shows no apparent gall, swelling, or deformation, although occasionally a slight swelling of the stalk occurs.

Numerous specimens, most of them reared during January and February, 1886, from galls collected in the District of Columbia.

Aulacidea harringtoni
Cryptic lettuce stem gall wasp [same entry applied to A abdita]

Hosts: Biennial lettuce (Lactuca biennis), Canada lettuce (L. canadensis), Florida lettuce (L. floridana), and possibly prairie lettuce (L. ludoviciana).

Gall location and description: Galls of these species are cryptic, meaning they are not outwardly visible and can only be located upon dissection of a galled stem. When dissected, the stem will have numerous brown, rounded chambers along the inside of the pith, each with a single insect.

Range: These galls are primarily known from the Northeastern United States and adjacent areas of Canada, from Ontario south to North Carolina and west to Oklahoma, but they are likely under-reported and may probably be found throughout the United States and Canada within the range of their host plants.

These species have unclear taxonomy and may be synonymous or may instead be composed of multiple true species, but each of the hosts listed above is believed to host cryptic galls induced by gall wasps of the genus Aulacidea. Museum specimens identified by Alfred C. Kinsey indicate that these galls may also occur in stems of prairie lettuce (L. ludoviciana), but the authors of this guide have yet to substantiate this claim.

Aulacidea bicolor (Gillette)

Aulax bicolor GILLETTE
Aulacidea bicolor KIEFFER
DALLA TORRE and KIEFFER
Aulax mulgediicola ASHMEAD
Aulacidea mulgidiicola ASHMEAD
Aulacidea mulgediicola KIEFFER
Aulacidea mulgedicola DALLA TORRE and KIEFFER

Gall. (Plate XXV, Fig. 5.) Consists simply of a thin-shelled larval cell imbedded in the pith of wild lettuce, Mulgedium (Lactuca) acuminata, and Lactuca canadensis. Usually there are numerous cells crowded together side by side in the pith, and externally the stem or stalk shows no apparent gall, swelling or deformation, although occasionally a slight swelling of the stalk occurs.

Habitat: Massachusetts; Connecticut; New York; New Jersey; District of Columbia; North Carolina; Illinois.

The types of Aulacidea bicolor Gillette are in the Illinois State Laboratory of Natural History and were sent to me for examination by Mr. C. A. Hart. I have also seen the types of Aulacidea mulgediicola Ashmead in the United States National Museum and thev are the same as A. bicolor.

Aulacidea harringtoni (Ashmead)

Aulax harringtoni ASHMEAD
Aulacidea harringtoni KIEFFER

Habitat: Canada (Ottawa).

The type, a single female, is in the United States National Museum. The thorax is somewhat shining, with the punctation very minute. The parapsidal grooves sharply defined, and the median groove short and not extending to the middle of the thorax. The anterior parallel lines are extremely fine and scarcely evident, and the scutellum is evenly rugose. The abdomen, legs, and two basal joints of the antennre are red brown, and the remaining joints of the latter are black. The gall is unknown.

Aulacidea cavicola (Ashmead)

Aulax cavicola
Aulacidea cavicola

Habitat: Missouri (Indian Cave). The types, two females of this species are in the United States National Museum, and nothing concerning the gall is known. I have examined the types, but am not prepared to give an opinion upon them without further study. I am, however, inclined to believe that the species will prove to be the same as Aulacidea tumida.