Druon linaria Kinsey, 1937

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 : 38-41

Druon linaria Kinsey, 1937 , stat. rev., comb. rev.

Figs. 101–112

Druon linaria Kinsey, 1937: 57 , female, gall.

Andricus linaria (Kinsey) : Weld, 1952a: 306.

Types examined. Holotype female “C. Victoria 21W Tams. 3200’, Mex. Gall 1.21.32., 27 fms. 2.25.32.”, “ Q. oleoides, Kinsey coll.”, red “ Druon linaria , Holo- Paratype ”, deposited in AMNH, NYC; examined by GM.

Additional material examined. Fifteen paratypes with the same labels as the holotype, deposited in AMNH, NYC; examined by GM .

Diagnosis. This is the only Druon species, other than D. quercuslanigerum var. striatum , that has the third metasomal tergum reticulate. Closely resembles D. quercuslanigerum var. quercuslanigerum , however D. linaria differs from the type specimens of D. quercuslanigerum in body color, being rusty brown with a dark anterior patch on the mesoscutum in D. linaria ( Figs. 106–109 ), while the body is yellowish without darker spots on the mesoscutum in D. quercuslanigerum var. quercuslanigerum ( Figs. 157–160 ); flagellomeres with similar thickness in D. linaria ( Fig. 104 ), while they widen towards the distal end of the antenna in D. quercuslanigerum ( Fig. 155 ); notauli slightly convergent in D. linaria , but very strongly convergent in D. quercuslanigerum ( Fig. 158 ); the median mesoscutal line is absent in D. linaria , but present in D. quercuslanigerum ( Fig. 158 ); central propodeal area with a few weak rugae in D. linaria ( Fig. 109 ), but smooth in D. quercuslanigerum ; as mentioned above the metasoma sculpture also differs between D. linaria and D. quercuslanigerum var. quercuslanigerum . D. quercuslanigerum var. striatum has the third metasomal tergum reticulate as in D. linaria ( Fig. 111 ), but the head is trapezoid in frontal view ( Fig. 177 ) and the second metasomal tergum has weak striae in D. quercuslanigerum var. striatum ( Fig. 189 ) while the head is transversally ovate in frontal view ( Fig. 101 ) and the second metasomal tergum is smooth in D. linaria ( Fig. 110 ).

Redescription. Asexual female ( Figs. 101–111 ). Body, antenna, mandibles, palpi, legs uniformly rusty brown.

Head alutaceous, with sparse setae, denser on lower face, transversally ovate, 1.3× as broad as high and slightly broader than mesosoma in frontal view; 2.2× as broad as long in dorsal view. Gena alutaceous, not broadened behind eye in frontal view, narrower than transverse diameter of eye in lateral view. Malar space alutaceous, with striae radiating from clypeus and not reaching eye, malar sulcus absent. Eye 3.5× as high as length of malar space. Inner margins of eyes parallel. POL 3.6× as long as OOL, OOL as long as diameter of lateral ocellus and slightly shorter than LOL, all ocelli ovate, of same size. Transfacial distance subequal to height of eye; toruli located in the upper half of head, frons shorter than lower face, diameter of antennal torulus 1.6× as long as distance between them, distance between torulus and eye slightly less than to diameter of torulus; lower face alutaceous, with dense white setae, without striae; slightly elevated median area delicately coriaceous, glabrous, with a few setae. Clypeus nearly quadrangular, broader than high, smooth, glabrous, with long setae along ventral edge; ventrally rounded, not emarginate and without median incision; anterior tentorial pit small, rounded, distinct, epistomal sulcus distinct, clypeopleurostomal line well impressed. Frons uniformly alutaceous, without striae or setae, interocellar area alutaceous. Vertex, occiput and postocciput alutaceous to coriaceous; postgena smooth, without setae; posterior tentorial pit large, elongated, area below impressed; occipital foramen as high as height of postgenal bridge; hypostomal carina emarginate, continuing into straight postgenal sulci that diverge strongly toward occipital foramen, postgenal bridge ventrally 4.0x narrower than dorsally, near occipital foramen. Antenna slightly longer than head+mesosoma, with 12 flagellomeres (suture between F12 and F11 indistinct but visible), not broadened distally, pedicel longer than broad; scape+pedicel longer than F1; F1 as long as pedicel and longer than F2; F2 1.2× as long as F3, F3 1.2× as long as F4, F4=F5, F6–F12 nearly equal in length; placodeal sensilla on F4–F12, absent on F1–F3.

Mesosoma 1.2× as long as high, with a few white setae, setae denser along propleuron and on lateral propodeal area. Pronotum smooth, glabrous dorsally, with numerous delicate parallel striae extending laterally onto entire pronotum; anterior rim of pronotum impressed, foveolate; propleuron smooth, shining. Mesoscutum uniformly and entirely reticulate, with a few white setae anteriorly, shorter than broad (greatest width measured across mesoscutum level with base of tegulae). Notaulus complete, posteriorly converging; in most posterior part distance between notauli shorter than distance between notaulus and side of mesoscutum; anterior parallel line invisible; parapsidal line marked with more delicate sculpture; median mesoscutal line absent; parascutal carina broad, reaching notaulus. Mesoscutellum rounded; disk of mesoscutellum dull rugose, with stronger rugae laterally and posteriorly, overhanging metanotum, with sparse setae; circumscutellar carina present, not well defined posteriorly. Mesoscutellar foveae transverse, 2.0× as broad as high, smooth, divided by broad rugose elevated central carina. Mesopleuron including speculum entirely striato-reticulate, with delicate interrupted parallel striae, extending across mesopleuron, with long white setae only in posteroventral part; mesopleural triangle smooth, glabrous, without striae, with long white setae; dorsal and lateral axillar areas smooth, glabrous, with a few setae and piliferous points; axillula with delicate parallel longitudinal striae; subaxillular bar smooth, glabrous, triangular, posteriorly higher than height of metanotal trough; metapleural sulcus reaching mesopleuron slightly above half of its height, separating smooth, glabrous area, with some setae; upper part of sulcus indistinct. Metascutellum alutaceous, glabrous, rectangular, with glabrous ventral impressed area; metanotal trough smooth, glabrous; central propodeal area smooth, glabrous, with weak rugae; lateral propodeal carinae present, bent outwards in posterior 1/3; lateral propodeal area smooth, glabrous, with long white setae, with rounded bump at the base of each seta. Nucha with numerous irregular sulci dorsally and laterally. Tarsal claws with basal lobe.

Fore wing longer than body, hyaline, with short cilia on margin, veins brown, radial cell open, 3.0× as long as broad; Rs and R1 nearly reaching wing margin; areolet small, triangular, closed, indistinct. Rs+M distinct on 3/4 of its length, its projection reaching basalis slightly below its mid height.

Metasoma slightly longer than head+mesosoma, slightly longer than high in lateral view; second metasomal tergum with white long setae anterolaterally, smooth; third metasomal tergum reticulated and all subsequent terga, including hypopygium, with micropunctures. Prominent part of ventral spine of hypopygium 2.0× as long as broad in ventral view. Body length 1.6–2.2 mm (n = 5).

Gall ( Fig. 112 ). Creamy white furry leaf galls in clusters (usually of 3 or fewer galls) on the underside of leaves, at the base of the leaf, yellowing a bit with age. Individual hairs on the gall are straight, not long. Each cluster closely compact, circular, up to 9 mm in diameter, 3 mm high.

Biology. Only the asexual generation is known, which induces woolly leaf galls on Q. oleoides (Section Virentes ). Galls mature in late autumn; adults emerge in February–March of the following year.

Distribution. Mexico: Eastern Sierra Madre Oriental, Tamaulipas (Kinsey 1937).

Comments. Pujade-Villar et al. (2016) erroneously synonymized this species under A. quercuslanigera (Ashmead) . After revising the type material, both species are transferred to Druon and we consider D. linaria and D. quercuslanigerum to be two independent valid species with distinct morphological differences. Some specimens of D. quercuslanigerum collected in Mexico have the third metasomal tergum reticulate as in typical D. linaria , but are clearly different based on other characters. Perhaps the sharing of this metasomal character (that is otherwise absent in Druon ) reflects occasional gene flow among these two species where their distributions abut (see also the Discussion).

Figures

FIGURES 101–105. Druon linaria, comb. rev., asexual female. 101–103, head: 101, frontal view, 102, dorsal view, 103, posterior view. 104, antenna. 105, pronotum, dorsal view.

FIGURES 106–109. Druon linaria, comb. rev., asexual female. 106, mesosoma, lateral view. 107, mesoscutum, dorsal view. 108, metascutellum, dorsal view, 109, metascutellum and propodeum, posterodorsal view.

FIGURES 110–112. Druon linaria, comb. rev., asexual female. 110, metasoma, lateral view. 111, third and subsequent terga, with reticulate sculpture. 112, gall.

FIGURES 157–160. Druon quercuslanigerum var. quercuslanigerum, comb. nov., asexual female (Florida). 157, mesosoma, lateral view. 158, mesoscutum and mesoscutellum, dorsal view. 159, mesoscutellum, dorsal view, 160, metascutellum and propodeum, posterodorsal view.

FIGURES 151–156. Druon quercuslanigerum var. quercuslanigerum, comb. nov., asexual female (Florida). 151–154, head: 151, frontal view, 152, dorsal view, 153, lateral view, 154, posterior view. 155, antenna. 156, mesosoma and propleura, frontal view.

FIGURES 177–182. Druon quercuslanigerum var. striatum, comb. nov., asexual female (North Mexico). 177–180, head: 177, frontal view, 178, dorsal view, 179, lateral view, 180, posterior view. 181, antenna. 182, propleura, frontal view.

FIGURES 187–189. Druon quercuslanigerum var. striatum, comb. nov., asexual female (North Mexico). 187, fore wing. 188–189, metasoma: 188, lateral view, 189, dorsal view.