Disholandricus reniformis ( McCracken & Egbert, 1922 ) Melika & Pujade-Villar & Nicholls & Cuesta-Porta & Stone, 2021

Melika, George, Pujade-Villar, Juli, Nicholls, James A., Cuesta-Porta, Victor & Stone, Graham N., 2021, Three new Nearctic genera of oak cynipid gall wasps (Hymenoptera: Cynipidae: Cynipini): Burnettweldia Pujade-Villar, Melika & Nicholls, Nichollsiella Melika, Pujade-Villar & Stone, Disholandricus Melika, Pujade-Villar & Nicholls; and re-establishment of the genus Paracraspis Weld, Zootaxa 4993 (1), pp. 1-81 : 57-61

Disholandricus reniformis ( McCracken & Egbert, 1922) , comb. nov.

Figs 166–178 , 193

Andricus reniformis McCracken & Egbert, 1922: 31 , female, gall.

Disholcaspis reniformis (McCracken & Egbert) : Melika & Abrahamson, 2002: 172.

Types examined. The holotype is in the California Academy of Sciences Collection, type No. 5798. Types were not examined .

Material examined. Two females labelled as „ USA, California, 30 km NE of Arnold, Code CA302 ; leg. J.A. Nicholls , 2007.11.06; Quercus vacciniifolia ”, deposited in the collection of PHDNRL .

Diagnosis. This is the only species in Disholandricus in which the malar space has delicate striae radiating from the clypeus that extending across the half length of the malar space; the body is brown, with large black marks on the mesoscutum, propodeum, metasoma ( Figs 172–175 ); mesoscutellar foveae are in the form of a semilunar depression with a few parallel delicate longitudinal rugae, without the central elevated carina ( Figs 173–175 ) while in the other three species the malar space lacks striae, the entire body is yellowish brown to yellow; mesoscutellar foveae are with smooth bottom, without striae and divided by a narrow central elevated carina.

Description. Asexual female ( Figs 166–178 ). Head dark brown to black, except light brown gena and narrow stripe along eyes on lower face and frons; antenna uniformly dark brown; propleuron dark brown; mesoscutum reddish brown except dark brown patch on anterior half between notauli, darker stripes along parapsidal lines, darker mesopleuron and ventral part of mesosoma; propodeum dark brown; legs uniformly reddish brown except darker hind coxae; metasoma dorsally dark brown, laterally reddish brown.

Head microreticulate, transverse, with dense white setae, denser posteriorly, 1.9x as broad as long in dorsal view; 1.3x as broad as high in frontal view and broader than mesosoma. Gena alutaceous, broadened behind eye in frontal view; in lateral view, ventral part distinctly broader than transverse diameter of eye and in dorsal part as broad as transverse diameter of eye. Malar space reticulate, with delicate striae radiating from clypeus and extending across half the malar space, malar sulcus absent; eye 2.1x as high as length of malar space. Inner margins of eyes parallel. Ocelli elevated above vertex in frontal view; POL 1.3x as long as OOL; OOL 2.1x as long as diameter of lateral ocellus, 1.6x as long as LOL; ocelli ovate, all three equal in size. Transfacial distance 1.3x as long as height of eye and 1.6x as long as height of lower face (distance between antennal rim and ventral margin of clypeus); toruli level with upper half of eye; diameter of antennal torulus 1.6x as long as distance between them, distance between torulus and eye margin 1.3x as long as diameter of torulus. Lower face and the median area microreticulate, without striae, with white setae. Clypeus ovate, flat, slightly broader than high, delicately coriaceous, ventrally rounded, emarginate, not incised medially; anterior tentorial pit deep, epistomal sulcus and clypeo-pleurostomal line distinct. Frons, interocellar area, area between toruli, vertex, occiput, postgena and postocciput microreticulate; postocciput around occipital foramen impressed, smooth, glabrous, without parallel striae above occipital foramen; posterior tentorial pits large, deep, elongate; height of oral foramen slightly greater than height of postgenal bridge+occipital foramen; occipital foramen as high as height of postgenal bridge; hypostomal carina emarginate, continuing into postgenal sulcus; postgenal sulci V-shaped, gradually bent outwards; postgenal bridge smooth, glabrous, anteriorly broader than width of occipital foramen. Antenna longer than head+mesosoma and slightly shorter than length of body, with 12 flagellomeres, all flagellomeres with long dense setae; pedicel slightly longer than broad, F1 longer than length of scape+pedicel, and slightly longer than F2, F2 slightly longer than F3, F3 slightly longer than F4, F5 slightly longer than F6, F7 till F11 gradually shorter in length, F12 1.5x as long as F11; placodeal sensilla on F5–F12.

Mesosoma longer than high in lateral view. Pronotum delicately coriaceous, with dense white setae, without striae laterally, emarginate and foveolate along lateral edge; propleuron dark brown to black, delicately coriaceous, with dense white setae. Mesoscutum delicately coriaceous, with piliferous points and uniformly distributed white sparse setae; longer than broad (width measured across base of tegulae); notaulus complete, with smooth bottom, converging posteriorly; median mesoscutal line absent; anterior parallel line distinct, impressed, reaching to 1/3 of mesoscutum length; parapsidal line not impressed, indicated by smooth stripe, reaching to 1/2 of mesoscutum length; parascutal carina narrow, extending anteriorly to pronotum. Transscutal articulation deep, distinct. Mesoscutellum slightly longer than broad, trapezoid, with subparallel sides, rounded posteriorly; shorter than mesoscutum, uniformly coriaceous, overhanging metanotum; mesoscutellar foveae in the form of semilunar depressions, with smooth, glabrous bottoms, with few parallel delicate longitudinal rugae, without central elevated carina. Mesopleuron, including speculum, delicately microreticulate to alutaceous, glabrous, with setae; mesopleural triangle smooth, with white setae and some delicate irregular short rugae. Metapleural sulcus reaching mesopleuron at half of its height, lower part of sulcus delimiting triangular area with dense white setae, upper part of sulcus distinct, delimiting narrow area; dorsal and lateral axillar areas coriaceous, with dense setae; axillar carina broad, with longitudinal striae; subaxillular bar triangular, smooth, glabrous, at the most posterior end slightly higher than the height of metanotal trough. Metascutellum delicately coriaceous, as high as the height of smooth, glabrous ventral impressed area; metanotal trough smooth, glabrous, with white setae and indistinct longitudinal parallel rugae. Lateral propodeal carinae distinct, bent slightly outwards in posterior third, reaching anterior edge of propodeum; central propodeal area smooth, glabrous, without rugae; lateral propodeal area with dense white setae and piliferous points; nucha short, glabrous without sulci dorsally, with delicate longitudinal sulci laterally. Tarsal claws with acute basal lobe.

Forewing longer than body, with light brown veins, margin with dense cilia; radial cell opened, 5.0x as long as broad, R1 and Rs not reaching wing margin; areolet triangular, with indistinct veins; Rs+M indistinct, visible for 2/3 of the distance between areolet and basalis, its projection reaching basalis slightly above its half height.

Metasoma longer than head+mesosoma, slightly longer than high in lateral view; second metasomal tergum reaching almost 1/2 of metasoma length in dorsal view, smooth, glabrous with a few white setae anterolaterally; subsequent terga and hypopygium smooth, glabrous, without setae; prominent part of ventral spine of hypopygium as long as broad, gradually narrowing until apex, with long setae extending far beyond apex of spine, forming a distinct tuft. Body length 3.6–3.8 mm (n = 2).

Gall. ( Fig 193 ). The detachable, multilocular, kidney-shaped stem galls are mottled-red, yellow and green when young, turning to a tan color when mature. Galls are up to 30 mm long and 15 mm in diameter. Larval chambers are located radially around the central core. Galls produce honeydew ( Russo 2006; Nicholls et al. 2017).

Biology. Only the asexual generation is known, inducing galls on Q. chrysolepis and Q. vacciniifolia . Galls develop in summer; adults emerge only 2–3 years after the galls are formed.

Distribution. USA: California ( Burks 1979).

Figures

FIGURES 166–171. Disholandricus reniformis, comb. nov., asexual female. 166–169, head: 166, frontal view, 167, dorsal view, 168, lateral view, 169, posterior view. 170, antenna. 171, mesosoma and propleura, frontal view.

FIGURES 172–175. Disholandricus reniformis, comb. nov., asexual female. 172, mesosoma, lateral view. 173, mesoscutum, dorsal view. 174, mesoscutellum, dorsal view. 175, metascutellum and propodeum, posterodorsal view.

FIGURES 176–178. Disholandricus reniformis, comb. nov., asexual female. 176–178, metasoma: 176, lateral view, 177, dorsal view, 178, ventral view.

FIGURES 193–195. Disholandricus asexual galls. 193, D. reniformis, comb. nov.. 194–195, D. truckeensis, comb. nov.:194, lateral view, 195, ventral view. Fig 193 courtesy of J. Gross.