Neuroterus alexandrae Nicholls & Melika, 2021

Melika, George, Nicholls, James A., Abrahamson, Warren G., Buss, Eileen A. & Stone, Graham N., 2021, New species of Nearctic oak gall wasps (Hymenoptera: Cynipidae, Cynipini), Zootaxa 5084 (1), pp. 1-131 : 90-93

Neuroterus alexandrae Nicholls & Melika , sp. nov.

Figs. 329–343

urn:lsid:zoobank.org:act:0DB5A8A3-E596-4FB2-95C0-9F472A64AAEE

Type material: HOLOTYPE female “ USA, Arizona, Stoneman Lake Road at l17, leg. J. Nicholls, 2008.04.10. Code AZ1908, spAZb14; ex Quercus turbinella ” . PARATYPES (15 females and 6 males): 10 females and 2 males with the same labels as the holotype; 5 females and 4 males “ USA, Arizona, 5 km N of Payson , leg. J. Nicholls, 2008.04.12, Code AZ1894, ex Quercus turbinella ”. The holotype , 2 females and 1 male are deposited at the USNM , 13 females and 5 males at the PHDNRL .

Etymology. Named after Prof. Alex Rowe, wife of Prof. Graham N. Stone (Institute of Evolutionary Biology, University of Edinburgh, UK).

Diagnosis. Neuroterus alexandrae belongs to Kinsey’s subgenus Neospathegaster . It is one of only two Neuroterus known from the southwestern US that induce round bud galls. Closely resembles N. stonei . In N. alexandrae the head is 1.6× as broad as long in dorsal view, the notaulus is complete, marked with slightly impressed lines, the mesopleuron and speculum alutaceous, glabrous, the metasoma shorter than head+mesosoma, slightly longer than high in lateral view; in males POL 13.0× as long as OOL, while in N. stonei the head is 2.2× as broad as long in dorsal view, the notaulus absent, the mesopleuron and speculum uniformly delicately coriaceous, the metasoma as long as head+mesosoma, as long as high in lateral view; in males POL 4.8× as long as OOL.

Description. Sexual female ( Figs. 329–331, 334, 336–341 ). Head, mesosoma and metasoma dark brown to black; mandibles, maxillary and labial palpi light brown; pedicel, F1 and F2 light brown; scape, F3–F12 dark brown to black; legs light brown.

Head alutaceous, with sparse white setae, 1.4× as broad as high and narrower than mesosoma in frontal view, 1.6× 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, without striae, with malar sulcus; eye 3.7× as high as length of malar space. Inner margins of eyes parallel. POL 2.9× as long as OOL, OOL shorter than diameter of lateral ocellus and shorter than LOL, all ocelli ovate, of same size. Transfacial distance 0.9× as wide as height of eye, diameter of antennal torulus slightly longer than distance between them, distance between torulus and eye nearly equal to diameter of torulus; lower face and slightly elevated median area uniformly delicately coriaceous, without striae. Clypeus trapezoid, coriaceous, broader than high; ventrally rounded, broadly emarginate, without median incision and with a few long setae; anterior tentorial pit large, rounded, epistomal sulcus and clypeo-pleurostomal line distinct, broad. Frons and slightly elevated interocellar area alutaceous, with short white setae, without striae. Vertex, occiput, postocciput, postgena alutaceous, with rare setae; occipital foramen slightly higher than height of postgenal bridge; hypostomal carina emarginate, continuing into indistinct postgenal sulci which are not united. Antenna longer than head+mesosoma, with 12 flagellomeres, pedicel subglobular; F1 1.7× as long as pedicel, F1 slightly longer than F2, F2 1.2× as long as F3, F3=F4=F5, subsequent flagellomeres shorter, nearly equal in length, F12 slightly longer than F11, placodeal sensilla on F2–F12.

Mesosoma slightly longer than high, with rare white setae. Pronotum uniformly alutaceous; propleuron smooth, glabrous, with few setae; anterior margin invaginated, smooth, glabrous, not foveolate. Mesoscutum alutaceous, with few setae; nearly as long as broad (greatest width measured across mesoscutum at level of base of tegulae). Notaulus complete, marked with slightly impressed lines, alutaceous; anterior parallel line indistinct; parapsidal line marked with impressed area, alutaceous; median mesoscutal line absent; circumscutellar carina broad, reaching above tegula. Mesoscutum emarginate posterolaterally, slightly elevated above dorsal axillar area, V-shaped posteriocentrally. Transscutal articulation absent. Mesoscutellum slightly longer than broad, ovate, broadest in posterior 1/3; posteriorly rounded, uniformly alutaceous, strongly overhanging metanotum; anteriorly with impressed triangular smooth, glabrous area. Mesopleuron and speculum alutaceous, glabrous, invaginated along ventral margin; mesopleural triangle smooth, glabrous, with a few white setae; dorsal axillar area alutaceous, lateral axillar area smooth, glabrous; subaxillular bar smooth, glabrous, at posterior end slightly shorter than height of metanotal trough; metapleural sulcus indistinct, reaching mesopleuron in upper 1/3 of its height, upper part of sulcus indistinct. Metascutellum smooth, glabrous, 2.0× as long as height of smooth, glabrous ventral impressed area; metanotal trough smooth, glabrous; central propodeal area trapezoid, smooth, glabrous, with delicate rugae radiating from nucha, posteriorly 3.0× as broad as anteriorly; lateral propodeal carinae distinct, gradually diverging towards nucha; lateral propodeal area smooth, glabrous, with some setae. Nucha without sulci. Tarsal claws simple, without basal lobe.

Forewing longer than body, hyaline, margin with long dense cilia, R+Sc, M, M+Cu1, Cu1, R1, 2r dark brown, RS, M, Rs+M veins yellow, radial cell open, 3.8× as long as broad; R1 and Rs nearly reaching wing margin, areolet triangular, well-delimited, Rs+M distinct along full length, reaching basalis slightly below half its height.

Metasoma shorter than head+mesosoma, slightly longer than high in lateral view; second metasomal tergite extending to 1/3 of metasoma length in dorsal view, with a few white setae anterolaterally, without micropunctures; subsequent tergites smooth, glabrous, without micropunctures. Hypopygium without micropunctures, prominent part of ventral spine of hypopygium short, slightly longer than broad in ventral view, with a few setae ventrally which do not extend beyond apex of spine. Body length 2.0– 2.2 mm (n = 10).

Male ( Figs. 332–333, 335 ). Similar to female but height of eye 1.5× the length of transfacial distance, malar space very short; POL 13.0× as long as OOL, OOL very short, lateral ocellus nearly reaching eye; inner margins of eyes converging ventrally; ocelli large; interocellar area elevated; antenna with 13 flagellomeres, F1 slightly curved, apical 2/3 broader than basal 1/3, F13=F12, placodeal sensilla on F2–F13. Body length 1.9–2.2 mm (n = 5).

Gall. ( Figs. 342–343 ). Spherical, unilocular bud galls, 3–4 mm in diameter, on terminal or axillary buds. Gall surface smooth and shiny, initially green, sometimes developing mottled or striped patterning in red or purple. Possibly the same as the undescribed gall pictured in Fig. 25 of Weld (1960).

Biology. Only a sexual generation is known, which induces bud galls on Q. turbinella . Galls mature in April– May, adults emerge soon afterwards. Given the somewhat nondescript morphology of the gall, two females from different collection sites were sequenced for cytb and ITS2 to confirm the morphological assessment of species identity. The cytb sequences differed by 0.46%, while ITS2 sequences were identical (GenBank OK346306 – OK346307 , OK350665 – OK350666 ) .

Distribution. USA, Arizona, Mogollon Rim area.

Figures

FIGURES 329–336. Neuroterus alexandrae Nicholls & Melika, sp. nov., sexual generation. 329–331, head, female: 329, frontal view, 330, dorsal view, 331, posterior view. 332–333, head, male: 332, frontal view, 333, dorsal view. 334–335, antenna: 334, female, 335, male. 336, forewing, part, female.

FIGURES 337–341. Neuroterus alexandrae Nicholls & Melika, sp. nov., sexual generation, female: 337, mesosoma and propleura, frontal view, 338–338, mesosoma: 338, lateral view, 339, dorsal view. 340, metascutellum and propodeum, posterodorsal view. 341, metasoma, lateral view.

FIGURES 342–343. Neuroterus alexandrae Nicholls & Melika, sp. nov., sexual generation, galls.

FIGURES 24–28. Andricus archboldi Melika & Abrahamson, sp. nov., asexual generation, female. 24, mesosoma, lateral view. 25–26, mesosoma, dorsal view. 27, metascutellum and propodeum, posterodorsal view. 28, metasoma, lateral view.