Belenocnema treatae

Belonocnema floridanus

Dryorhizoxenus floridanus

Arizona

California

Louisiana

New Mexico

Oklahoma

Texas

Cynipidae

Belonocnema

Quercus geminata

Alabama

Florida

Georgia

Mississippi

North Carolina

South Carolina

Quercus virginiana

Virginia

Belonocnema treatae (sexgen)

Belenocnema treatae Mayr.

Dryorhizoxenus floridanus ASHMEAD

Gall. (Plate LI, Fig. 1.) In clusters around the rootlet of live oak (Quercus virginiana). Polythalamous. Irregular in shape, somewhat wedge-shaped, soft, fleshy and of the consistency of a potato when fresh. Externally rough, irregular and of a yellowish color. Hard, brown and woody when dry. Internally composed of numerous cells one above another, and separated by thick fleshy partitions. Length from 10 to 20 mm. 

Habitat. Florida. 

The types are in the United States National Museum.

The species of Holcaspis and their galls

Belonocnema treatae Mayr

Dryorhizoxenus floridanus Ashmead
Belonocnema floridanus

The type galls of this species were found while ploughing under a live oak (Quercus virginiana Miller) in March. They were just below the surface on the small rootlets (up to 10 mm. in diameter) and in clusters every 4 or 5 inches. They are described as irregular, somewhat wedge-shaped, soft and fleshy, easily detached, of a yellowish color, the first true root gall to be described in this country. Two hundred flies were reared. The galls are still preserved in the United States National Museum, black or brownish and very similar to the dried galls of the sexual generation of Trigonaspis. 

The writer has never seen the fresh galls, but on two occasions has found the dried-up galls of what was probably this species on the roots of Quercus geminata Small, at St. Petersburg and Clearwater, Florida, in November. In each case they were on the roots of saplings whose leaves bore immense numbers of globular, tan-colored galls, described in 1861 by Osten Sacken as Cynips q. virens. This suggests that these pea galls on leaf might be the alternating generation of Belonocnema treatae, but further observations or experimental evidence will be necessary to prove it. The type galls in the United States National Museum have a label in Doctor Ashmead's hand "agamic female of B. treatae Mayr," showing that he had already suspected this relationship. The writer also has reared adults from these leaf-pea galls and they prove to be all females and to belong to the genus Belonocnema, thus strengthening the supposition. The writer thus proposes to transfer the maker of this oak leaf-pea gall to Belonocnema, leaving the proof of the association with treatae to others. It appears, however, that the maker of these pea galls is still undescribed. Ashmead reared a single fly in February supposedly from over 200 of these galls and described it as Cynips q. virens, transferring it to Andricus later, but the type fly in the United States National Museum has a question mark after the genus. This type is in bad condition, but agrees with the description, and is plainly a Disholcaspis and agrees with Disholcaspis ficigera, a gall of which had evidently been mixed in with the others by mistake, and such a gall was found in the Ashmead duplicate gall collection in a box of oak leaf-pea galls which may have been his breeding cage. Thus the single fly reared was associated with the wrong gall, a mistake which would not have occurred had the species been described from adequate material. As the classification of the Cynipidae must be based upon the adults rather than upon their work, the maker of the stem gall known in literature as ficigera must take the oldest name applied to it, namely, virens, and the maker of the leaf gall needs description. However the leaf-pea gall-fly of Florida proves to be different from those from similar galls in Texas so that there are two species to describe. Although somewhat outside the scope of the present paper, these changes are here included, and the synonomy of each species follows, together with field notes on each. 

American gallflies of the family Cynipidae producing subterranean galls on oak

Belonocnema treatae sex.gen.

Quercus virginiana, geminata
"Root" galls
Cluster of wedge-shaped, soft, fleshy yellowish galls, 12-19 mm long on rootlets in March. Like Fig 56 [Callirhytis myrtifoliae, a flower gall on Quercus myrtifolia--a mistake?]

[Photo caption (no photo)]
Q virginiana. Fleshy white galls in a cluster similar to the above [Fig 51, Xanthoteras radicola], in early spring. 

Cynipid galls of the eastern United States

Belonocnema treatae (Mayr, 1881)

Belenocnema [sic] treatae Mayr, 1881 sexual generation

Hosts: Quercus virginiana and (rarely) geminata

Gall: irregular shaped, multilocular galls often in clusters on the small rootlets. 

Biology:  Sexual-generation adults emerge from mid-March to end of April, corresponding with the timing of leaf flush of their main host Q. virginiana

Remarks: Few specimens of this species have been collected from Q. geminata, which is unsurprising given the much later leaf flushing time of Q. geminata

Distribution: AL, FL, GA, MS, NC, SC

One hundred and sixty years of taxonomic confusion resolved: Belonocnema (Hymenoptera: Cynipidae: Cynipini) gall wasps associated with live oaks in the USA