Striatoandricus tenuicornis ( Bassett, 1881 ) Cuesta-Porta & Melika & Nicholls & Stone & Pujade-Villar, 2022

Cuesta-Porta, Victor, Melika, George, Nicholls, James A., Stone, Graham N. & Pujade-Villar, Juli, 2022, Re-establishment of the Nearctic oak cynipid gall wasp genus Druon Kinsey, 1937 (Hymenoptera: Cynipidae: Cynipini), with description of five new species, Zootaxa 5132 (1), pp. 1-92 : 80-82

Striatoandricus tenuicornis ( Bassett, 1881) , comb. nov.

Figs. 253–264

Cynips tenuicornis Bassett, 1881: 92 , female, gall.

Diplolepis tenuicornis (Bassett) : Weld 1926: 34.

Andricus tenuicornis (Bassett) : Weld 1951: 636.

Type examined. Holotype female “Mule Pass Mnts., Arizona ”, E.T. Cox coll.”, “ Bassettia tenuicornis W. B. Bass ”, red label “Paratype No. 52971 USNM ”, handwriting Weld label “ Diplolepis tenuicornis ”.

Additional material examined. Four females, all labelled as “Hopk. US 15639”, “Reared Jan. 23.22”, “ Quercus arizonica ”, “Oracle, Ariz.”, “ L. H.Weld Collector”, Weld’s handwritten label “ Diplolepis tenuicornis (Bass.) det. L. H.Weld”.

Diagnosis. Morphologically most closely resembles S. barriosi (Medianero & Nieves Aldrey, 2019) known from Panama, both having the head and mesosoma dark brown to black, the metasoma reddish brown; the notaulus complete, entirely reticulate pronotum, second metasomal tergum entirely striate, not areolate-reticulate, without smooth dorsolateral area; the mesoscutum longer than broad; mesopleuron entirely and uniformly reticulate, without smooth areas; Rs+M inconspicuous, not reaching basalis, its projection reaching basalis in its lower half ( Cuesta-Porta et al. 2020). But in S. barriosi the dorsal part of the mesopleuron is smooth, while in S. tenuicornis the entire mesopleuron is reticulate, except a small part of the speculum which is smooth, shining. Two species, S. sanchezi Pujade-Villar, 2020 and S. georgei ( Pujade-Villar, 2011) known from Mexico, differ by having the notaulus incomplete; in S. tenuicornis the notaulus is complete. Also S. nievesaldreyi ( Pujade-Villar, 2011) known from Mexico has an entirely sculptured mesopleuron and the second metasomal tergum dorsolaterally smooth, shining, while in S. tenuicornis the entire mesopleuron is reticulate, except a small part of the speculum which is smooth, shining and the second metasomal tergum dorsolaterally striate.

Galls. Densely hairy hemispherical masses attached by a single small point to the upper or under surface of the leaves. They are from 10-20 mm in diameter. The woolly hairs are of a dull russet color and entirely hide the polythalamous gall beneath. The gall interior contains small and extremely thin-walled larval cells. Between them there are a few thin fibrous plates or lamellae separating open spaces. An average size gall contains 14 larval cells ( Bassett 1881).

Biology. Only an asexual generation is only known, inducing galls on Q. arizonica .

Distribution. USA: Arizona, Mule Pass Mountains ( Bassett 1881).

Figures

FIGURES 253–258. Striatoandricus tenuicornis, comb. nov., asexual female. 253–256, head: 253, frontal view, 254, dorsal view, 255, lateral view, 256, posterior view. 257, antenna. 258, mesosoma and propleura, frontal view.

FIGURES 259–262. Striatoandricus tenuicornis, comb. nov., asexual female. 259–261, mesosoma: 259, lateral view, 260–261, dorsal view. 262, metascutellum and propodeum, posterodorsal view.

FIGURES 263–264. Striatoandricus tenuicornis, comb. nov., asexual female, metasoma. 263, lateral view. 264, dorsal view.