Feron roberti (agamic)

Feron amphorus (agamic)

Feron caepula (agamic)

Feron tetyanae (agamic)

Feron tecturnarum (agamic)

Feron izabellae (agamic)

Feron discale (agamic)

Feron cylindratum (agamic)

Feron atrimentum (agamic)

Feron atrimentum (sexgen)

Feron bakkeri (agamic)

Feron californicum (agamic)

Feron crystallinum (agamic)

Feron crystallinum (sexgen)

Feron albicomus (agamic)

Feron discularis (agamic)

Feron dumosae (sexgen)

Feron gigas (agamic)

Feron gigas (sexgen)

Feron kingi (agamic)

Feron kingi (sexgen)

Feron parmula (agamic)

Feron pattersonae (agamic)

Feron pattersonae (sexgen)

Feron rucklei (agamic)

Feron scutellum (agamic)

Feron serranoae (agamic)

Feron splendens (agamic)

Feron stellare (agamic)

Feron stellulum (agamic)

Feron sulfureum (agamic)

Feron syndicorum (agamic)

Feron tibiale (agamic)

Feron tubifaciens (agamic)

Feron verutum (agamic)

Feron vitreum (agamic)

Feron apiarium (agamic)

Feron clarkei (sexgen)

Feron comatum (sexgen)

Feron roberti Melika, Nicholls & Stone, sp. nov.

Gall (Fig. 310). Pinkish leaf galls, turret-like with bristles all around, covered with more or less crystalline, fine, hair-like fibers, similar to F. sulfureum, F. tibiale and F. tubifaciens, however, in larger clusters (20+ galls) up to 20 mm wide and 25–30 mm long.

Biology. Only the asexual generation is known, which induces leaf galls on Q. rugosa (section Quercus, subsection Leucomexicana). Galls mature in the autumn dropping only with the leaf; adults emerge next year, in late March–April.
Distribution. USA, Arizona.

Feron amphorus (Weld, 1926) comb. nov.

Gall (Fig. 24). The gall is on the underside of leaf, either side of midrib but not on it, red, reddish-purple or brownish, with pale brown apical dimple, 3 mm in diameter, 4–5 mm height, the hole at apex about 1 mm in diameter, surface with very short pilosity. A hollow cylinder, with a short petiole at the base, swollen more or less in the middle and tapering to the apex at which there is a small hole leading into a deep cavity at the bottom of which is the thin-walled larval cell (Weld 1926)

Biology. Only the asexual generation is known which induces galls on Q. arizonica, Q. oblongifolia and Q. turbinella (section Quercus, subsection Leucomexicana), and Q. pungens (section Quercus, subsection Polymorphae). Galls mature in autumn, drop with leaves.
Distribution. USA: Arizona, New Mexico.

Feron caepula (Weld, 1926), comb. nov.

Gall (Fig. 83). Small leaf galls on underside of leaf, 3 mm in diameter with small point in centre of gall, shaped rather like an onion or garlic bulb, pinkish to reddish-brown.

Biology. Only the asexual generation is known, which induces galls on Q. pungens (section Quercus, subsection Polymorphae) and the section Quercus, subsection Leucomexicana oaks: Q. arizonica, Q. oblongifolia, Q. turbinella (Burks 1979). The asexual galls mature by October–November, and adults emerge by April. 
Distribution. USA: Arizona, New Mexico (Burks 1979)

Feron tetyanae Melika sp. nov.

Gall (Fig. 428). Reddish-yellow furry leaf gall mass, a gregarious cluster of individual cells. Hairs covering the gall cluster are quite brittle and crystalline. On underside of leaf, to 20 mm long, projecting from leaf by up to 15 mm.

Biology. Only the asexual generation is only known, which induces galls on Q. arizonica, Q. oblongifolia, Q. turbinella and Q. toumeyi (section Quercus, subsection Leucomexicana) and on Q. gambelii (section Quercus, subsection Dumosae) (Burks 1979). The gall matures in late autumn and adults start emerging the next spring. This species is newly recognized as being distinct from F. tecturnarum (based on both morphology and DNA sequences); all specimens we have examined from previous collectors taken in the USA south-west and identified as F. tecturnarum show the diagnostic characters of F. tetyanae, so we consider that all records of F. tecturnarum from the USA should actually be attributed to the new taxon F. tetyanae. 

Distribution. USA: New Mexico, Arizona.

Feron tecturnarum Kinsey, 1920 comb. nov

Gall (Figs 407–408). Reddish-yellow furry leaf gall mass; a gregarious cluster of individual cells, 10–25 galls,
placed on the underside of leaf, to 20 mm long projecting from leaf by up to 15 mm.

Biology. The asexual generation is only known, which induces galls on Q. potosina (section Quercus, subsection Leucomexicana). Previous host records for the name Andricus tecturnarum from white oaks found in the southwest of the USA (e.g. Weld 1960, Burks 1979) are almost definitely attributable to the newly described species F. tetyanae, which is newly recognised in this study as being distinct from F. tecturnarum (based on both morphology and DNA sequences). The gall matures in late autumn, adults start emerging the next February.

Distribution. Mexico: San Luis Potosi (Kinsey 1920, authors).

Feron izabellae Melika, Nicholls & Stone, sp. nov.

Gall (Fig. 227). A small (up to 5mm diameter) monolocular spangle gall on the underside of leaves. Initially a disc-shaped gall lying flat against the leaf surface, pink in middle and around the edge with cream circle in between. When galls mature the opposite sides of the disc fold up and touch. Informally called the pink bowtie gall wasp in Russo (2006, 2021).

Biology. Only the asexual generation is known which induces spangle leaf galls on Q. berberidifolia, Q. douglasii, Q. dumosa (= Q. durata), Q. garryana (all section Quercus, subsection Dumosae). Galls mature in September–October. Adults emerge soon afterwards.

Distribution. USA: CA (authors).

Feron discale (Weld, 1926), comb. nov.

Gall (Fig. 173). A spangle gall, on the underside of leaf, 3.6–4.0 mm diameter, monolocular, yellow-green when young and growing, turn brown when mature, with raised rim and raised center, convex on upper surface, underside concave, the transversely placed larval chamber occupying the full height of the gall. A single or a few galls on one leaf (Weld 1926).

Biology. The asexual generation is only known, which induces galls on Q. pungens (section Quercus, subsection Polymorphae), Q. arizonica and Q. turbinella (both section Quercus, subsection Leucomexicana). Galls mature in late autumn; adults were cut out from galls in November; probably overwintering in galls and emerging in spring. 
Distribution. USA: Arizona, New Mexico (Burks 1979).


Feron cylindratum (Kinsey, 1937), comb. nov.

 Xystoteras cylindratum Kinsey 1937a: 77, female, gall.
Liodora cylindratum (Kinsey): Melika & Abrahamson 2002: 160 (synonymized Liodora with Andricus); Pujade-Villar 2003: 234 (mentioned this combination). 
Andricus cylindratum (Kinsey): Pujade-Villar 2003: 234.

Gall (Fig. 161). Small, naked, hollow cylinders scattered on the underside of leaves. Each gall is regularly cylindrical, a bit swollen below the tip, a bit restricted basally, up to 5.0 mm in length and 2.5 mm in diameter. The exterior of the gall fairly smooth, entirely naked except for a blue or purplish scurf. The body of gall hollow, open at top, the open cavity penetrating to a third or a half of the gall, separated from the larval cell by a thin partition; larval cell floored with a thicker partition beneath which another cavity is to be found. Young galls straw and light rose pink, sometimes touched more purple red, the whole touched with an ashy-blue scurf; older galls becoming burnt red to purple brown or dark, dirty brown. Each gall separated, often occurring in great numbers and dense masses, usually on under surfaces, rarely on upper surfaces of leaves. 

Biology. Only the asexual generation is known, inducing galls on Q. deserticola (= Q. texcocana) (section Quercus, subsection Leucomexicana). Galls mature in autumn; adults emerge from February to mid-March.

Distribution. Mexico: Mexico City, Puebla (Kinsey 1937).

Feron atrimentum (Kinsey, 1922)

Gall. Asexual galls (Fig. 50) are monolocular, conical, flat-based, detachable, on lower leaf margin. Sides nearly straight, flaring slightly at base. Red and yellow striped when fresh, turning to brown and yellow with age. Basal larval cell oval from lateral view, 1.6 mm in diameter, 0.8 mm high, pubescent. Upper surface of larval cell coriaceous with sparse pubescence; brown, darker towards center. Gall height 3.6–4.6 mm, width 3.0–4.6 mm.

Biology. Matching of generations was first presented in Dailey & Sprenger (1973b). Alternate sexual and asexual generations are also confirmed herein using DNA data, with four individuals (three asexual females, one sexual female) sequenced for cytb. Cytb sequences were on average 0.35% divergent between individuals (range 0–0.70%; GenBank accessions OK041496, OQ446191–OQ446193).

Feron atrimentum is associated with Q. douglasii, Q. dumosa, Q. john-tuckeri and Q. lobata (section Quercus, subsection Dumosae). The sexual generation females emerge throughout April and usually oviposit in the lower leaf surface near the margin. Asexual galls develop over the following three months. Pupation occurs during late October to November; asexual females emerge in late winter and oviposit in leaf buds. Sexual generation galls usually reach full size by mid-March (Dailey & Sprenger 1973b).

Distribution. USA: California.

Feron atrimentum (Kinsey, 1922)

Gall. The sexual gall (Fig. 49) is monolocular, spherical, 3–5 mm in diameter, smooth, green when growing, becoming paler later, mature galls when dried are yellow-brown; larval cell is blue-black and sometimes visible though outer layers of the gall. Walls of the gall are thin, the larval chamber is also thin-walled, 1.5 mm in diameter and connected with the outside wall by a tangle of dense fibers. The gall is in the leaf tissue, projecting equally on both sides.

Biology. Matching of generations was first presented in Dailey & Sprenger (1973b). Alternate sexual and asexual generations are also confirmed herein using DNA data, with four individuals (three asexual females, one sexual female) sequenced for cytb. Cytb sequences were on average 0.35% divergent between individuals (range 0–0.70%; GenBank accessions OK041496, OQ446191–OQ446193).

Feron atrimentum is associated with Q. douglasii, Q. dumosa, Q. john-tuckeri and Q. lobata (section Quercus, subsection Dumosae). The sexual generation females emerge throughout April and usually oviposit in the lower leaf surface near the margin. Asexual galls develop over the following three months. Pupation occurs during late October to November; asexual females emerge in late winter and oviposit in leaf buds. Sexual generation galls usually reach full size by mid-March (Dailey & Sprenger 1973b).

Distribution. USA: California.

Feron bakkeri (Lyon, 1984), comb. nov.

Gall (Fig. 71). A monolocular, cup-shaped leaf spangle gall, 3–3.5 mm in height. The larval cell occupies the base of the cup whose margins are collapsed at maturity (Lyon 1984).

Biology. Only the asexual generation is known, which induces galls on Q. dumosa (section Quercus, subsection Dumosae). The galls appear on the leaves during the early summer until August. At this time the galls are red and contain small larvae. Pupation occurs in late October and early November; adults can be cut out in early December; however, normal emergence takes place in February–March, or even later.

Distribution. USA: California (Lyon 1984).

Feron californicum (Beutenmueller, 1911), comb. nov.

Gall (Fig. 96). The monolocular spangle leaf gall is on the upper surface of the leaves, rounded, flattened disclike, slightly elevated toward the middle, pinkish or purplish, with the apex sometimes yellowish. Sides of the gall are flat and very thin; the larval chamber is in the central elevated part; the diameter of the gall is 3–4 mm, height 1 mm (Beutenmueller 1911).

Biology. Only the asexual generation is known, which induces galls on Q. cornelius-mulleri, Q. douglasii and Q. dumosa (section Quercus, subsection Dumosae). The gall matures by November and the adult emerges in
January.

Distribution. USA: California.


Feron crystallinum (Bassett, 1900) comb. nov.

Gall. Asexual galls (Fig. 135). Bristly-haired gall masses 35 mm long by 25 mm wide on the underside of leaves composed of small, individual, elliptical or spherical, monothalamous galls, 12–14 mm high, 7 mm in diameter. Each gall usually with a slightly curved beak at the apex and a sparse coating of crystalline white, rose pink, red, or brown hairs (Russo 2021).

Biology. Alternate asexual and sexual generations were matched by Doutt (1960). Alternate sexual and asexual generations are also confirmed herein using DNA data, with four individuals (three asexual females, one sexual female) sequenced for cytb and three individuals (two asexual females, one sexual female) sequenced for cytb. Cytb sequences grouped into two haplotypes that were 0.23% divergent (GenBank accessions KX683596, MZ030743, OQ446195–OQ446196) and ITS2 sequences were identical among the three individuals (GenBank accessions OQ448237–OQ448239). Asexual galls in autumn on leaves, adults emerge in January–February; sexual galls in spring, adults emerge in March. Both generations develop on oaks from section Quercus, subsection Dumosae: Q. douglasii, Q. dumosa and Q. garryana.

Distribution. USA: California.

Feron crystallinum (Bassett, 1900) comb. nov.

Gall. Sexual galls (Fig. 148–149) monolocular, they are mostly on the upper surface of leaves, singly or in small groups, green with straw coloured apex, conical, slightly curved. The gall has numerous long cottony, white hairs projecting laterally, which are longer than the greatest width of the gall. The gall is 2.5 mm in length, with the base 1.0 mm tapering to the tip. The position of the gall is indicated on the opposite (usually lower) side of leaf by a pale coloured elliptical swelling (Doutt 1960). The gall is difficult to distinguish from other similar sexual galls such as F. comatum, F. dumosae and F. kingi.

Biology. Alternate asexual and sexual generations were matched by Doutt (1960). Alternate sexual and asexual generations are also confirmed herein using DNA data, with four individuals (three asexual females, one sexual female) sequenced for cytb and three individuals (two asexual females, one sexual female) sequenced for cytb. Cytb sequences grouped into two haplotypes that were 0.23% divergent (GenBank accessions KX683596, MZ030743, OQ446195–OQ446196) and ITS2 sequences were identical among the three individuals (GenBank accessions OQ448237–OQ448239). Asexual galls in autumn on leaves, adults emerge in January–February; sexual galls in spring, adults emerge in March. Both generations develop on oaks from section Quercus, subsection Dumosae: Q. douglasii, Q. dumosa and Q. garryana.

Distribution. USA: California.

Feron albicomus (Weld, 1952), comb. nov.

Gall (Fig. 12). The asexual monolocular, round, bristly pubescent galls are mostly on the underside and, sometimes, the dorsal surface of leaves. Galls are covered with short, stellate white hairs. Galls occur singly or in scattered groups along the edges of the leaves or near the midrib. Galls are 4 mm high and wide (Russo 2006, 2021; Weld 1952b, 1957).

Biology. The asexual generation is only known, which induces galls on Q. garryana (section Quercus, subsection Dumosae), the gall matures by October; adults emerge in April.

Distribution. USA: north California (Russo 2006, 2021; authors), Oregon (Burks 1979).

Feron discularis (Weld, 1926), comb. nov.

Gall (Figs 187–188). Disk-shaped, about 6 mm in diameter by 1 mm thick, single or scattered in small numbers on underside of leaf in autumn. The upper surface is slightly concave, the edge sinuate, the margin reflexed nearly to the leaf surface. The transversely placed larval cell occupies the full height of the gall. Exit hole on top surface (Weld 1926).

Biology. The asexual generation only is known, inducing galls on Q. garryana (section Quercus, subsection Dumosae). Galls mature in September, adults were cut out in November.

Distribution. USA: CA (Weld 1926).

Feron dumosae (Weld, 1957), comb. nov.

Gall (Fig. 202). Small, 2–3 mm, conical gall on leaf edge, slightly pubescent, fresh galls red-pinkish to pale brown, leaf blade twists slightly at the gall. The gall is difficult to distinguish from other similar sexual galls of F. comatum, F. crystallinum and F. kingi.

Biology. Rosenthal (1968) and Rosenthal & Koehler (1971) erroneously stated that Liodora dumosae was the sexual generation of Andricus kingi. Dailey & Menke (1980) subsequently corrected this mistake by demonstrating that Rosenthal & Koehler had mis-identified their sexual generation wasps as L. dumosae and instead had reared the then unknown sexual generation of A. kingi. Evans (1972) proposed that L. dumosae was the sexual generation of Andricus pattersonae and transferred the later to Liodora under the new name combination L. pattersonae; this error was reiterated by Dailey & Menke (1980). However, this matching with A. pattersonae is in disagreement with genetic data presented herein (see under F. pattersonae), nor did Evans perform any rigorous biological experiments to match generations. In addition, Evans appears to have mis-identifed his asexual generation galls (Fig 15 of Evans 1972) as they are too small and pale to be those of A. pattersonae and instead look like those of the new species F. rucklei described herein. Thus, until rigorous rearing experiments are conducted or genetic data are obtained, we consisder Feron dumosae to be a valid distinct species known only from its sexual generation.

Galls occur on multiple oaks from section Quercus, subsection Dumosae: Q. douglasii, Q. dumosa, Q. garryana and Q. lobata. They mature in May and adults emerge soon after.

Distribution. USA: California.

Feron gigas (Kinsey, 1922), comb. nov.

Galls. Asexual spangle galls (Fig. 215) about 4 mm in diameter, usually on the upper side of the leaf, saucer shaped, with a thin crenate margin when young, with a prominent hump in center. The mature gall has a lens-shaped larval cavity inside, on the floor of which is a thin, white, circular disk with radiating prominent lines.

Biology. Alternation of sexual and asexual generations was determined by Dailey & Sprenger (1973a). Alternate sexual and asexual generations are also confirmed herein using DNA data, with four individuals (three asexual females, one sexual male) sequenced for cytb and three individuals (two asexual females, one sexual male) sequenced for cytb. Cytb sequences were on average 0.82% divergent (range 0–1.66%; GenBank accessions KX683598, OQ446198–OQ446199) and ITS2 sequences were identical among the three individuals except for two additional bases within a polyA region in one sample (GenBank accessions OQ448240–OQ448242).

This species induces galls on Q. douglasii and Q. dumosa (section Quercus, subsection Dumosae). Young asexual galls are present in August, mature in autumn; asexual adults emerge in February. Sexual galls are mature in April; adults emerge by the end of April.

Distribution. USA: California.

Feron gigas (Kinsey, 1922), comb. nov.

Galls. Sexual galls are small, 1–2 mm in diameter, round, pale yellow, on catkin coming off catkin stem at same place as stamens, sometimes on edge of leaf.

Biology. Alternation of sexual and asexual generations was determined by Dailey & Sprenger (1973a). Alternate sexual and asexual generations are also confirmed herein using DNA data, with four individuals (three asexual females, one sexual male) sequenced for cytb and three individuals (two asexual females, one sexual male) sequenced for cytb. Cytb sequences were on average 0.82% divergent (range 0–1.66%; GenBank accessions KX683598, OQ446198–OQ446199) and ITS2 sequences were identical among the three individuals except for two additional bases within a polyA region in one sample (GenBank accessions OQ448240–OQ448242).

This species induces galls on Q. douglasii and Q. dumosa (section Quercus, subsection Dumosae). Young asexual galls are present in August, mature in autumn; asexual adults emerge in February. Sexual galls are mature in April; adults emerge by the end of April.

Distribution. USA: California.

Feron kingi (Bassett, 1900), comb. nov.

Galls. The asexual gall (Fig. 240) is red, monolocular, detachable, cone-shaped on both sides of the leaves, 5 mm high and 3–5 mm broad at the base. The cone rises from a flared, cup-shaped base, which is narrowly attached to the leaf. The apex of the gall is pointed, with a blunt tip. The gall is covered by fine pubescence; the larval chamber is large, occupying the most of the gall base. Occurs singly or in groups, up to dozens (Russo 2006, 2021).

Biology. Liodora dumosae was erroneously named as the sexual generation of A. kingi (Rosenthal 1968; Rosenthal & Koehler 1971, Burks 1979), but subsequent detailed examination of the type material showed that L. dumosae is a distinct species and Rosenthal’s material represented the previously unknown and undescribed sexual generation of A. kingi (Dailey & Menke 1980; our examinations); herein we formally describe sexual A. kingi for the first time. Alternate sexual and asexual generations are also confirmed herein on the basis of similarity in cytb sequence data. Four individuals (two asexual females, one sexual female, one sexual male) had cytb sequences that were on average 0.23% divergent (range 0–0.47%; GenBank accessions OK041496, OQ446201–OQ446203).

Asexual galls have been collected from Q. douglasii, Q. dumosa, Q. garryana, and Q. lobata (section Quercus, subsection Dumosae) in late September and October; adults emerge early the following spring (Burks 1979). Mature sexual galls have been collected in late March and the beginning of April from Q. berberidifolia, Q. douglasii, and Q. lobata (section Quercus, subsection Dumosae); adults emerge soon after under laboratory conditions.

Distribution. USA: California.

Feron kingi (Bassett, 1900), comb. nov.

Galls. The sexual gall (Fig. 239) is small, 2–3 mm, conical gall on the leaf margin and/or catkin, slightly pubescent. Fresh galls are pinkish to pale brown, turn dark purple-black when mature, the leaf blade twists slightly at the gall. The gall is difficult to distinguish from similar sexual galls of F. comatum, F. crystallinum and F. dumosae.

Biology. Liodora dumosae was erroneously named as the sexual generation of A. kingi (Rosenthal 1968; Rosenthal & Koehler 1971, Burks 1979), but subsequent detailed examination of the type material showed that L. dumosae is a distinct species and Rosenthal’s material represented the previously unknown and undescribed sexual generation of A. kingi (Dailey & Menke 1980; our examinations); herein we formally describe sexual A. kingi for the first time. Alternate sexual and asexual generations are also confirmed herein on the basis of similarity in cytb sequence data. Four individuals (two asexual females, one sexual female, one sexual male) had cytb sequences that were on average 0.23% divergent (range 0–0.47%; GenBank accessions OK041496, OQ446201–OQ446203).

Asexual galls have been collected from Q. douglasii, Q. dumosa, Q. garryana, and Q. lobata (section Quercus, subsection Dumosae) in late September and October; adults emerge early the following spring (Burks 1979). Mature sexual galls have been collected in late March and the beginning of April from Q. berberidifolia, Q. douglasii, and Q. lobata (section Quercus, subsection Dumosae); adults emerge soon after under laboratory conditions.

Distribution. USA: California.

Feron parmula (Bassett, 1900), comb. nov.

Gall (Fig. 268). Minute, flat, sessile, saucer shaped, red spangle gall, on the underside of the leaves, 2.0 mm in diameter, with a slight elevation in the center, where the small larval cell is located (Russo 2006, 2021).

Biology. Only the asexual generation is known, which induces galls on Q. douglasii, Q. dumosa, Q. garryana, Q. lobata (section Quercus, subsection Dumosae), and Q. engelmannii (section Quercus, subsection Leucomexicana) (Burks 1979). Galls mature in April, adults emerge after soon (Russo 2006, 2021).

Distribution. USA: California (Burks 1979).

Feron pattersonae (Fullaway, 1911), comb. nov.

Gall. Asexual gall (Figs 281–282) Relatively large, thin, flat spangle gall on underside of leaves, detachable, monolocular. about 9 mm in diameter, with irregular way margin. Green when young, becoming yellow or tan when mature. 

Biology. Andricus pattersonae and Liodora dumosae were erroneously paired by Evans (1972; restated by Dailey & Menke 1980). Evans (1972) appears to have mis-identified the asexual gall he found as A. pattersonae; his Figure 15 shows a gall much more similar to the new species F. rucklei described herein. Molecular data also refute Evans’ pairing, instead establishing the correct matching of A. pattersonae with A. pedicellatus, with the associated synonymisation herein. Four individuals (two asexual females [=A. pattersonae], two sexual females [=A. pedicellatus]) were sequenced for cytb and ITS2. Cytb sequences were on average 1.14% divergent (range 0.23– 1.90%; GenBank accessions OQ446204–OQ446206) and ITS2 sequences were on average 0.25% divergent (range 0–0.42%, including identical alleles in one asexual and one sexual individual; GenBank accessions OQ448243–OQ448246).

Asexual galls have been recorded from leaves on section Quercus, subsection Dumosae oaks: Q. douglasii, Q. dumosa, Q. garryana, and Q. lobata (Burks 1979), the gall matures by late autumn, adults emerge in late winter. Sexual galls occur on leaves of Q. douglasii (Burks 1979) and mature in April; adults emerge soon after.

Distribution. USA: California (Burks 1979).

Feron pattersonae (Fullaway, 1911), comb. nov.

Gall. Sexual gall (Fig. 283) is a small, elongate capsule, 5–7 mm long, 1.0–1.5 mm wide, attached by a slender pedicel to the edge of the leaf, unilocular. The gall is sharp-tipped, broadest near the tip, continuing into a slender, thread-like stem, 5–12 mm long, evidently a continuation of a leaf vein. The gall is thin-walled, entirely hollow.

Biology. Andricus pattersonae and Liodora dumosae were erroneously paired by Evans (1972; restated by Dailey & Menke 1980). Evans (1972) appears to have mis-identified the asexual gall he found as A. pattersonae; his Figure 15 shows a gall much more similar to the new species F. rucklei described herein. Molecular data also refute Evans’ pairing, instead establishing the correct matching of A. pattersonae with A. pedicellatus, with the associated synonymisation herein. Four individuals (two asexual females [=A. pattersonae], two sexual females [=A. pedicellatus]) were sequenced for cytb and ITS2. Cytb sequences were on average 1.14% divergent (range 0.23– 1.90%; GenBank accessions OQ446204–OQ446206) and ITS2 sequences were on average 0.25% divergent (range 0–0.42%, including identical alleles in one asexual and one sexual individual; GenBank accessions OQ448243–OQ448246).

Asexual galls have been recorded from leaves on section Quercus, subsection Dumosae oaks: Q. douglasii, Q. dumosa, Q. garryana, and Q. lobata (Burks 1979), the gall matures by late autumn, adults emerge in late winter. Sexual galls occur on leaves of Q. douglasii (Burks 1979) and mature in April; adults emerge soon after.

Distribution. USA: California (Burks 1979).

Feron rucklei Melika, Nicholls & Stone, sp. nov.

Gall. (Figs 322–323). Small spangle leaf gall, 5 mm across, somewhat star-shaped, flat against the leaf surface but with a central bump. Pale yellow with a darker centre when growing, becoming tan when mature. Typically multiple galls scattered across a single leaf. The same gall is depicted and described as an unknown species in Russo (2006, 2021; informally called the disk gall wasp) and Weld (1957, Fig. 174).

Biology. Only the asexual generation is known, which induces spangle leaf galls on Q. garryana (section Quercus, subsection Dumosae). Galls mature in November; adults emerge soon after under laboratory conditions. This gall appears to be depicted in Evans (1972) in his Figure 15; those galls were also collected from Q. garryana in the same area (southern Vancouver Island). Evans experimentally matched these asexual galls with the sexual generation of Liodora dumosae, but mistakenly called them A. pattersonae (which has been matched to a different sexual form, A. pedicellatus, using DNA evidence elsewhere in this study). Hence we hypothesise that F. rucklei may be the alternate asexual form of F. dumosae, but further DNA evidence is required to test this suggestion.

Distribution. Canada, British Columbia, Ruckle Provincial Park. It is the first record of this genus for Canada.


Feron scutellum (Weld, 1930), comb. nov.

Gall (Fig. 328). A cup-shaped leaf spangle gall, up to 4.5 mm in diameter and 3.5 mm high, purple-brown with a whitish bloom, attached to under side of leaf. The edge of the cup is thin, not in-rolled. The larval cell is 2 mm long by 0.7 mm in diameter and lies transversely at the very base of the cup. The exit hole is into the bottom of cup.

Biology. The asexual generation is only known, which induces galls on Q. gambelii (section Quercus, subsection Dumosae) and Q. turbinella (section Quercus, subsection Leucomexicana). Galls mature in late autumn, and adults were cut out from galls in December-January (Weld 1930).

Distribution. USA: AZ (Weld 1930).

Feron serranoae Pujade-Villar & Cuesta-Porta, sp. nov.

Gall (Fig. 341). Brownish rounded unilocular galls on the underside of leaves, with an apical hole. Up to 6-8 mm in diameter.

Biology. Only the asexual generation is known, which induces galls on an unidentified white oak Quercus sp. (section Quercus, subsection Leucomexicana). The gall was found mature in January and the adults emerged soon after.

Distribution. Only known from Sierra de Guadalupe, Mexico State (Mexico).

Feron splendens (Weld, 1919), comb. nov.

Gall (Fig. 353). Single or scattered on the underside of leaf. Cylindrical with ends and middle slightly swollen, 2.0 mm in diameter and 3–5 mm high, with a crystalline appearance, covered with short stout blunt spines from which run faint decurrent ridges. Sessile, often lop-sided, spines more numerous on basal third. The gall is rosy red with a straw yellow band around the middle and some yellow at either end. The basal third is solid, with a thinwalled larval cell in the middle of the gall while the distal third or more is tubular with a slightly flared open end. The exit hole is in the hollow portion (Weld 1919).

Biology. Only the asexual generation is known, which induces leaf galls on Q. grisea, Q. turbinella, and Q. x undata (section Quercus, subsection Leucomexicana). Galls mature in late autumn; the larvae transform to adults in autumn but remain in the gall all winter and emerge the following spring in April–May.

Distribution. USA: AZ, NM (Burks 1979); Mexico: Chihuahua, Durango.

Feron stellare (Weld, 1926), comb. nov.

Gall (Fig. 366). A hemispherical gall, 3–4 mm in diameter and 2 mm high, covered with short, blunt crystalline protuberances with a circle of 12–15 longer, broad projections at the base, attached singly or scattered in small numbers on the underside of the leaf. The galls are yellowish-white, often tinged with red. The larval cell lies transversely in the very base of the gall and above it is a cavity above which the crystalline wall of the upper part of the gall is very thick (Weld 1926).

Biology. Only the asexual generation is known, which induces leaf galls on Q. douglasii and Q. garryana (section Quercus, subsection Dumosae) in autumn, the adults emerge the next spring in March (Weld 1926).

Distribution. USA: California (Burks 1979).

Feron stellulum (Burnett, 1974) comb. nov.

Gall (Fig. 371). Leaf gall. Monolocular and can be found on both sides of the leaves. Disk shaped (1.6-2.3 mm in diameter) with some points around the perimeter but erected on a long and slender pedicel, usually slightly broadening towards apex. The gall is almost twice as high as the diameter of the disk (2.3–5.6 mm in height). The surface is shiny and glabrous of a reddish colour, the pedicel is crimson, and the disk is rufous. Galls are found attached either to a secondary vein of the leaf blade or occasionally to the midrib, mature galls are typically associated with a brown necrosis around the point of attachment which extends laterally to the leaf-blade margin. Emergence holes made by the gall wasp are usually found in the lateral part of the gall disc (Burnett 1974).

Biology. Only the asexual generation is known, inducing galls on Q. dumosa (section Quercus, subsection Dumosae); adults start to emerge from February.

Distribution. USA: CA.

Feron sulfureum (Weld, 1926) comb. nov.

Gall (Fig. 383). A hollow cone, sessile at base and open at apex, densely covered with long sulphur-yellow spines, on under surface of leaf, single or scattered, sometimes as many as nine on a leaf but usually only one to three. The cone is up to 7 mm high by 4 mm in diameter at base, with a crystalline surface, white or rosy when growing, the spines up to 4 mm long and often rosy at the tip. The larval cell lies transversely just below the middle of gall and below it is a small obconical cavity reaching to point of attachment. The lower part of the large distal cavity above larval cell is constricted by a narrow circular shelf.

Biology. Only the asexual generation is known, which induces galls on multiple oaks fromsection Quercus, subsection Leucomexicana: Q. arizonica, Q. grisea and Q. oblongifolia. Galls mature in the autumn dropping only with the leaf; adults emerge in late March-April.

Distribution. USA, Arizona only.

Feron syndicorum Pujade-Villar & Cuesta-Porta, sp. nov.

Gall (Fig. 394). Yellow crystalline leaf gall mass (aggregation of galls, 5-20 galls) on underside of leaf, to 20 mm long projecting from leaf by up to 15 mm. Larval chambers easily detachable from leaf and crystalline pubescence extremely brittle.

Biology. Only the asexual generation is known, which induces galls on Q. potosina (section Quercus, subsection Leucomexicana). The gall matures in late autumn and the adults emerge soon after.

Distribution. Mexico, La Cumbre (Monte Escobedo, State of Zacatecas).

Feron tibiale Kinsey, 1937 comb. rev.

Gall (Fig. 440). Individual galls swollen, cylindrical, flaring at the broadened tip, covered with more or less crystalline processes, with a few broad filaments (chiefly at the base of each gall), with almost all of the fibers fine, hair-like. Galls clustered, forming a more or less solid and tangled mass up to 27 mm in diameter and 13 mm high. Purple rose and light brown when young, becoming light straw brown to russet, rosy brown, or dark brown with age (Kinsey 1937).

Biology. Only the asexual generation is known, which induces galls on section Quercus, subsection Leucomexicana oaks: Q. arizonica, Q. chihuahuensis, Q. deserticola (= Q. texcocana) according to Kinsey (1937); adults emerge mainly during January-February (Kinsey 1937). Quercus glabrescens, Q. glaucoides, Q. obtusata, and Q. rugosa are new host records for this study.

Two species described by Kinsey (1937), F. tostum and F. uterinum, are morphologically consistent with the series of specimens that Kinsey called F. tibiale. They simply represent geographical variants of that species and hence we synonymise the names in this study.

The conspecific status of the two morphological variants within this species (one with a smooth mesopleuron, the other having a mesopleuron with a transverse reticulated-carinated band) was confirmed using DNA sequence data. One individual from each of the two morphotypes was sequenced for cytb and ITS2; both individuals had identical sequences for both genes (GenBank accessions OQ446186, OQ446241, OQ448247–OQ448248).

Distribution. Mexico: Mexico City, Chihuahua, Durango, Querétaro (Kinsey 1937); also from the State of Mexico in this study.

Feron tubifaciens (Weld, 1926) comb. nov.

Gall (Fig. 475). Convex mass of tubular galls standing side by side in a compact cluster on the underside of the leaf. The mass measures up to 25 mm long by 15 mm wide. The individual galls are easily detached, white or creamcoloured, up to 9 mm long, tapering gradually from the base to a diameter of about 3 mm at the distal open end, the distal portion covered with tapering spines which are often rosy at the tip. The single larval cell lies midway along the length of the gall and measures about 2 mm long by 1.2 mm in diameter (Weld 1926).

Biology. Only the asexual generation is known, inducing galls on Q. garryana (section Quercus, subsection Dumosae) (Weld 1926, Burks 1979). Galls mature in October-November.

Distribution. USA: California.

Feron verutum Kinsey, 1937 comb. rev.

Gall (Fig. 488). Individual galls long and slender, uniformly cylindric or flaring at the top, more or less covered with distinctly crystalline processes all of which are broad and blunt, filamentous, not fine nor hairlike. The whole cluster forming a spiny mass in which the individual galls are still prominent, the clusters up to 30 mm in diameter and 12 mm high. Bright purple rose and straw colour when fresh, darkening with age (Kinsey 1937).

Biology. Only the asexual generation is known, which induces galls on section Quercus, subsection Leucomexicana oaks: Q. magnoliifolia, and Q. rugosa (Kinsey 1937). Fresh mature galls in January, adults emerge in April (Kinsey 1937). The type material is labelled as collected from Q. macrophylla, but Kinsey did not define the authorship of the host species. Two possible hosts coexist within the distribution of F. verutum: Q. magnoliifolia (= macrophylla Née), or Q. resinosa (= macrophylla sensu Trel.).

Distribution. Mexico: San Luis Potosi, Guanajuato (Kinsey 1937); also from Ciudad de Mexico state in this study.

Feron vitreum Kinsey, 1937 comb. rev.

Gall (Fig. 501). Individual galls long and slender, uniformly cylindrical or flaring at the top, fairly well covered with distinctly crystalline processes all of which are broad and blunt, filamentous, none of which are fine or hairlike. Galls clustered, forming a spiny mass in which the individual galls are quite prominent, the clusters up to 55 mm in diameter and 17 mm high. Bright purple rose and straw colour when fresh, darkening with age (Kinsey 1937).

Biology. Only the asexual generation is known, which induces galls in October-January, on section Quercus, subsection Leucomexicana oaks: Q. deserticola Trel. (= Q. texcocana Trel.), and Q. rugosa (= Q. rhodophlebia), adults emerge in April.

Kinsey (1937) described another species, F. validum, which we consider is morphologically consistent with Kinsey’s series of specimens of F. vitreum and simply represents a geographical variant of that species; hence we synonymise the name in this study.

Distribution. Mexico: Luis Potosi, Guanajuato (Kinsey 1937).

Feron apiarium (Weld, 1944), comb. nov.

Gall (Fig. 36). Solitary, sessile, on underside of leaf close to edge, shaped like an old-fashioned straw beehive, white or pinkish, up to 4.6 mm broad by 4.0 mm high. Inside is a large cavity with a transverse larval cell at the very base. During the winter on the ground the outer fleshy layer shrivels and the gall becomes more cylindrical (Weld 1944).

Biology. Only females are known. Leaf galls on Q. alba (section Quercus, subsection Albae). Mature galls in October; adults emerge next year, in February–March.

Distribution. USA: Washington DC, VA (Burks 1979).

Feron clarkei (Bassett, 1890), comb. nov.

Gall (Fig. 109). Galls in terminal and axillary buds, many-celled, smooth, bare, often hidden by bud scales.

Biology. Only the sexual generation is known, inducing bud galls on Q. alba (section Quercus, subsection Albae) and Q. stellata (section Quercus, subsection Stellatae). Adults emerge in early spring until May (Ashmead 1896).

Distribution. USA: MA, MO (Burks 1979).

Feron comatum (Weld, 1952), comb. nov.

Gall (Figs 122–123). Conical, 3.0 by 1.4 mm, tan when mature, thin walled, covered with crinkly white matted hairs. Produced singly at edge of leaf. The gall is difficult to distinguish from the sexual galls of F. crystallinum, F. dumosae and F. kingi, although this species has an eastern distribution rather than Pacific slope (but see also diagnosis to species above).

Biology. Only the sexual generation is known, inducing galls on Q. alba (section Quercus, subsection Albae). Galls mature in early spring; adults emerge in late April–May.

Distribution. USA: VA (Weld 1952b).

Re-establishment of the Nearctic oak cynipid gall wasp genus Feron Kinsey, 1937 (Hymenoptera: Cynipidae: Cynipini), including the description of six new species