Holotype : 1♀ in the Museo Nacional de Ciencias Naturales, Madrid, Spain (MNCN), mounted (glued) on a card. Mexico, Oaxaca, Comaltepec, 17°33'50"N, 96°33'20"W, ca. 2330 m alt.; ex gall Quercus zempoaltepecana (Quercus sect. Lobatae), gall collected 21/04/2018, insect emerged 30/04/2018. D. Castillejos-Lemus leg. Paratypes: 5♂, same data as holotype but emerged 1-3/05/2018. Two paratype ♂ were dissected and mounted on a stub for SEM observation in the MNCN. Other materials: 4♂, same data as paratypes, preserved in ethanol (in MNCN and Castillejos-Lemus collection, Morelia, Mexico). Additional material: 3 galls, one dissected (in MNCN).

Named after the strikingly-large size of the galls of this species.

This new species belongs to the group of Amphibolips species that have a forewing with a transversal clear band that is variable in size and extends towards medial and cubital veins to the ventral margin of the wing (Nieves-Aldrey et al. 2012). The aforementioned group comprises Amphibolips castroviejoi from Panama, Amphibolips trizonata Ashmead, 1896 from Arizona (USA) and the Mexican Amphibolips durangensis Nieves-Aldrey & Maldonado, 2012, A. dampfi and the recently described A. cibriani Pujade-Villar, 2018 (Pujade-Villar et al. 2018). However, the forewing pattern of the new species is different from that of all the referenced species. The transversal clear band is larger and broader and extends to two-thirds of the radial cell in both sexes and the basal third of the wing is more heavily infuscate in the male (Fig. 4A, B).

Amphibolips magnigalla shares with Amphibolips dampfi, A. castroviejoi and the other two new species described herein, a mesoscutellum emarginate posteriorly. However, the emargination is comparatively less deep in A. magnigalla (Figs 1C, 2C). Besides the main character of the forewing, the four species can be readily distinguished by the characters provided in the identification key in this paper.

Regarding the gall, the new species is easily distinguished by its large spindle-shaped gall (approximately 10 cm in length × 2.5 cm in diameter), which is at least 2× larger than any other spindle-shaped gall described from Mexico. Amphibolips fusus and A. durangensis induce galls morphologically similar to the gall of the new species. However, besides the differences in size, the inner structure of the gall induced by the referenced species is different, being filled with a dense soft tissue, while the inner structure of the gall induced by the new species is often almost empty, with visible radiating filaments from the central larval cell.

Body length: 5.8 mm (n = 1) for females; 5.2 mm (n = 3) for males.

Female (Fig. 4C). Body almost entirely black; antennae, except two basal segments, mandibles, metasoma ventrally, hypopygium and parts of tibiae and tarsi, chestnut. Forewing predominantly black infuscate, except a wide clear transversal band that starts in the distal two thirds of radial cell and extends towards discoidal and cubital cell, almost reaching ventral margin of forewing. Another non-infuscate band extended from the posterior part of the costal cell towards the Rs+M vein and reached the cubital vein (Fig. 4A).

Head, in dorsal view 2.3× wider than long. POL:OOL:DOL as 23:44:14. Head in anterior view (Fig. 1A) 1.2× wider than high, gena slightly broadened behind eye. Vertex, frons, lower face, gena and occiput with strong reticulate-rugose sculpture (Fig. 1B); two longitudinal carina present, extending from ventral margin of toruli to converge towards the anterior tentorial pits; irradiating carinae from clypeus absent; head moderately pubescent, except in vertex and frons. Clypeus more or less hexagonal, ventral margin strongly projecting over mandibles and slightly sinuate on anterior margin. Anterior tentorial pits well visible; epistomal sulcus and clypeo-pleurostomal lines slightly discernible. Malar space 0.7× height of compound eye. Toruli situated mid-height of compound eye; transfacial line 1.4× height of an eye; distance between antennal rim and compound eye slightly shorter than width of antennal socket including rim. Ocellar plate slightly raised.

Head posterior view (male) (Fig. 2B), heavily pubescent, with occiput coarsely rugose; dorsally the sculpture is transversely ribbed. Two carinae present, arising from dorsal part of the occipital foramen and ventrally continuing past posterior tentorial pits; posterior tentorial pits rounded; gular sulci united meeting at hypostoma. Posterodorsal margin of oral foramen not margined medially; hypostomal ridges well separated.

Mouthparts (male) (Fig. 2A), mandibles strong, exposed; with dense setae in base, right mandible with three teeth; left with two teeth. Cardo of maxilla not visible, maxillary stipes 4.1× as long as wide. Maxillary palp with five segments. Labial palp with three segments; apical peg of last labial and maxillary segments present.

Antenna (Fig. 3C), of moderate length, 0.5× as long as body length; with 13 antennomeres; flagellum not broadening towards apex; with relatively long, erect setae. Relative length/width of antennal segments as: 0.29(0.16):0.12(0.16):0.44(0.15):0.32(0.14):0.25(0.15):0.24(0.16):0.21(0.15):0.19(0.15): 0.17(0.14): 0.16(0.15):0.16(0.15):0.16(0.15):0.32(0.14). Pedicel (Fig. 3C) short, small, broader than long, 0.4× as long as scape; F1 1.4× as long as F2. F8-F10 as long as wide, F11 2.3× as long as wide, 2× as long as F10. Placodeal sensilla on F5-F11, disposed in dense rows of 6–8 sensilla, only in half dorsal area of each flagellomere.

Mesosoma in lateral view (Fig. 1E) 1.12× as long as high. Pronotum, moderately pubescent; lateral surface of pronotum with strong irregular reticulate rugose sculpture. Pronotum medially short; ratio of length of pronotum medially/laterally = 0.2. Pronotal plate indistinct dorsally.

Mesonotum. Mesoscutum (Fig. 1C) barely pubescent and with strong reticulate-rugose sculpture, the interspaces smooth and shining. Notauli somewhat obscured by the coarse sculpture, but visible; strongly convergent posteriorly; longitudinal median impression, not discernible. Anteroadmedian signa quite visible, extended back to near one half of mesoscutum; parapsidal signa distinct. Transscutal fissure narrow, sinuate. Mesoscutellum 1.2× as long as wide; about 0.7× as long as mesoscutum. Scutellar foveae (Fig. 1D) rounded, elongated posteriorly, about 0.5× as long as mesoscutellum, separated medially by a groove, the foveae are deep, mostly smooth anteriorly and crossed posteriorly by irregular transversal rugae, the intervals smooth, posterior margins indistinct. Mesoscutellum strongly coarsely rugose, with a deep and broad median longitudinal impression which makes the mesoscutellum strongly emarginate posteriorly (Fig. 1D); the emargination reaches anteriorly the scutellar foveae. In lateral view, the posterior emargination of mesoscutellum is seen as two, slightly curved upwards, horn-like projections. Mesoscutellum in lateral view with the posterodorsal extension of body of subaxillular strip short, not reaching one half of mesoscutellar height. Mesopleuron coarsely reticulate rugose, the rugae not as strong as in mesoscutum (Fig. 1E).

Metanotum. Metapectal-propodeal complex. Metapleural sulcus reaching posterior margin of mesopectus at about mid-height of metapectal-propodeal complex. Metascutellum rugose; metanotal trough smooth and pubescent. Median propodeal area (Fig. 1F) with some irregular strong longitudinal and transversal rugae; and densely pubescent; lateral propodeal carinae distinct, subparallel anteriorly and converging posteriorly.

Legs. Densely pubescent; femora and tibiae robust. Metatibia about as long as metatarsus; apical margin of metatarsomeres 1–4, with long strong erect setae. Metatarsal claws with strong triangular basal lobes or teeth.

Forewing (Fig. 4A), about as long as body, radial cell 3.2× longer than wide; open along anterior margin; areolet obsolete, obscured by infuscation. M and Cu1 veins nearly straight, not reaching wing margin. Rs+M not reaching basalis. First abscissa of radius (2r) slightly angled, not projected. Cu1 vein not branched in two veins. Apical margin with very short or obsolete hair fringe.

Metasoma (Fig. 3A, D), in dorsal view 1.6× as long as wide, in lateral view 1.2× as long as high. Second metasomal tergite covering about 0.7× length of metasoma. Anterior 2/3 smooth and shining; posterior one third with a band of micropunctures clearly visible; the punctate sculpture extended on subsequent tergites; ventral area of second metasomal tergite moderately pubescent. Projecting part of hypopygial spine moderately long (Fig. 3B); 4.6× as long as high in lateral view; laterally with long setae, longer than spine width, but not forming an apical patch.

Male (Figs 2A–F, 4B, D). Differs from the female as follows: smaller size, length 5.2 mm on average (n = 3). Body and wings almost completely black, except tarsomeres of anterior legs and apical segments of antennae. Antennae, legs and wings relatively longer. Antenna (Fig. 3E) with 14 segments. Antennal formula as: 0.24(0.15):0.13(0.15):0.6(0.11):0.39(0.13):0.35(0.14):0.35(0.14):0.32(0.12): 0.31(0.11):0.28(0.11): 0.27(0.1):0.27(0.1):0.27(0.1):0.26(0.1):0.24(0.1):0.23(0.08). F1 slightly curved and enlarged apically and flattened ventrally, 1.5× as long as F2; placodeal sensilla present in all the flagellomeres (Fig. 3F). Head 1.3× as wide as high; apical part of gena slightly expanded. Mesoscutellar impression not reaching the scutellar foveae (Fig. 2D). Scutellar foveae confluent, not separated by a sulcus. Forewing relatively longer 1.2× as long as body. Almost completely black, except the distal transversal clear band (Fig. 4B).

Gall (Fig. 5A–D). A large spindle-shaped gall with an elongated and narrow tip and base. The galls measure 100 × 25 mm on average. The surface of the gall is smooth, but some superficial longitudinal ridges are visible. The gall is monothalamic; the outer shell is thin, flexible and of fleshy consistency when it is fresh and becomes soft and light when it dries. They are light green without spots when they are fresh and light brown when they are dry. Internally (Fig. 5C), there is an oval larval cell in the centre of the gall (0.35 mm thick and 7 × 5 mm; n = 1). A spongy tissue occupies the entire space between the epidermis and the larval chamber, the outer shell is weakly attached to the internal spongy tissue when fresh and when the gall dries, the spongy tissue allows us to observe the radiant filaments, which extend from the larval chamber towards the internal walls of the galls (Fig. 5D). When it is dry, the gall is very fragile and can be easily crushed. At least half of the galls no longer showed spongy tissue when they were transferred to the laboratory. This caused the galls to collapse due to the fragility of the epidermis. Some of these collapsed galls presented internal modifications in the epidermis, probably caused by inquilines.

The galls develop on twigs of Quercus zempoaltepecana Trel. The gall closely resembles that of Amphibolips durangensis Nieves-Aldrey & Maldonado, 2012. However, the gall of A. magnigalla is distinguished by its larger size, which is at least 2× longer than that of A. durangensis and by its different internal structure, which is filled with less dense spongy tissue and radiant filaments (easily visible in the older galls).

A. magnigalla was found only in one site: Comaltepec (Oaxaca State, Mexico). The galls were relatively abundant on a single isolated tree, while we did not find galls on the nearby trees.

Sexual generation. The galls were collected at the end of April and the insects emerged shortly thereafter, in early May. It seems that it is normal for many insects to feed on the tissue of this species. A detached gall was observed in a field, relatively far from the tree, probably carried by a bird.

Holotype : 1♀ in the Museo Nacional de Ciencias Naturales (MNCN), Madrid, Spain, mounted (glued) on a card. Mexico, Oaxaca, Pozuelos, Ixtlán, 17°22.52'N, 96°26.88'W, ca. 3040 m alt., ex gall Quercus zempoaltepecana. Collected 21/04/2018; emerged 04/05/2018. D. Castillejos-Lemus leg. Paratypes: 4♂ and 2♀, same data as that of holotype; 1♀ and 1♂ paratype dissected and mounted on a stub for SEM observation. Additional material in ethanol: 3♂ and 1♀ (in the collection of Castillejos-Lemus, Morelia, Mexico), 1♂ (in MNCN). Eighteen galls, one dissected (in the collection of Castillejos-Lemus and the Colección Nacional de Insectos-UNAM).

Named after Dr Alfred Kinsey, one of the most prominent cynipidologists and the pioneer of the study of Amphibolips in Mexico.

Amphibolips kinseyi is very similar to A. dampfi Kinsey, 1937. We collected the new species in sites near where collections by A. Dampf were made (near Ixtlán, Oaxaca), the material of which was later described by Kinsey (Kinsey 1937). Both species share a strongly emarginate mesoscutellum and have a similar forewing colour pattern. However, after a close comparison with the male holotype, we found some diagnostic differences that allowed us to describe our specimens as different and new species. The forewings of the males of A. dampfi and A. kinseyi are similar, being predominantly black infuscate and have a reduced clear transversal band; however, in A. dampfi, the first radial abscissa (2r vein) is strongly angled and projected into the radial cell (Fig. 9C), while it is weakly angled and not projected in A. kinseyi (Fig. 9D). The postero-lateral projections of the mesoscutellum are more or less pointed or acute in the A. dampfi males (Fig. 9A), but are more rounded and flatter in the case of the new species (Fig. 9B). Additional distinguishing characters are given in the identification key provided herein. The female forewing of A. dampfi was not available for description, as it was apparently lost in the only female collected. However, the female forewing of this closely-allied new species is described here. Consistent with other Amphibolips species from Mexico, the female forewing is different from the male forewing. In this case, the female forewing has a clear transversal band, which is larger and more extended than that of the male (Fig. 8C).

Body length: 6.3 mm (n = 1) for females; 5.7 mm (n = 3) for males.

Female. Body predominantly black (Fig. 8A); head, except the red mandibles and the mesosoma, black; metasoma reddish postero-ventrally; antennal flagellum reddish in distal half; legs reddish except black basal part of coxae. Forewing (Fig. 8C) predominantly black infuscate, but much less infuscate above the cubital veins and below the M+Cu1 vein. There is a wide, clear, transversal band, which starts in the apex of the radial cell and extends towards the discoidal and cubital cells to the Cu1a vein but does not reach the latero-ventral margin of the forewing.

Head, in dorsal view 2.1× as wide as long; 0.8× as wide as mesosoma. POL 0.7× the OOL; lateral ocelli separated from inner margin of an eye for a distance of 3× the diameter of a lateral ocellus. Head in anterior view (Fig. 6A) 1.2× wider than high, gena slightly broadened behind eye. Vertex, frons, lower face and gena, with strong coarsely-rugose sculpture. A medial frontal pit visible followed by a sulcus addressed to the median ocellus. Face with two longitudinal carinae visible, extending from ventral margin of toruli to converge towards the space between the anterior tentorial pits; irradiating carinae from clypeus virtually absent; head moderately pubescent, except in vertex and frons. Clypeus more or less hexagonal, ventral margin strongly projecting over mandibles and weakly sinuate on anterior margin. Anterior tentorial pits well visible; epistomal sulcus and clypeo-pleurostomal lines visible. Gena slightly depressed basally and projected over the mandibles. Malar space 0.7× height of a compound eye. Toruli situated mid-height of compound eye; transfacial line 1.7× height of an eye; distance between antennal rim and compound eye 0.8× width of antennal socket including rim. Ocellar plate slightly raised.

Mouthparts (Fig. 6A), mandibles strong, exposed; with dense setae in base, right mandible with three teeth; left with two teeth.

Antenna (Fig. 6E), about one half as long as body length; with 13 antennomeres; 12 and 13 incompletely separated ventrally. Flagellum not broadening towards apex; with relatively long, erect setae. Relative length/width of antennal segments as: 0.28(0.16):0.16(0.16):0.52(0.16): 0.38(0.16):0.3(0.17):0.24(0.16):0.24(0.17):0.2(0.17):0.2(0.17):0.2(0.16):0.18(0.16):0.16(0.15):0.3(0.14). Scape slightly longer than wide, flattened and smooth ventrally. Pedicel, short, small, as long as wide, 0.5× as long as scape; F1 1.3× as long as F2, F11 2.3 times as long as wide, 2× as long as F10. Placodeal sensilla present on flagellomeres F3-F11, disposed in dense rows of 6–8 sensilla, only in half dorsal area of each flagellomere. Coeloconic and trichoidea sensilla are also present and visible (Fig. 6F).

Mesosoma in lateral view 1.3× as long as high. Pronotum, moderately pubescent; lateral surface of pronotum with strong irregular reticulate rugose sculpture (Fig. 6D). Pronotum medially short; ratio of length of pronotum medially/laterally = 0.2. Pronotal plate indistinct dorsally.

Mesonotum. Mesoscutum (Fig. 6C) barely pubescent and with strong coarse reticulate sculpture, the interspaces smooth and shining. Notauli shallow and crossed by the general sculpture, but well visible and almost complete; longitudinal median impression not visible. Anteroadmedian signa well marked, extended back to near one half of mesoscutum; parapsidal signa distinct. Transscutal fissure very narrow, sinuate. Mesoscutellum 1.3× as long as wide; about 0.5× as long as mesoscutum. Scutellar foveae ovoid elongated posteriorly, about 0.5× as long as mesoscutellum, separated medially by a deep groove, the foveae are deep, crossed by irregular transversal rugae, the intervals smooth, posterior margins shallowly indicated. Mesoscutellum strongly coarsely rugose, with a deep and broad median longitudinal impression which makes the mesoscutellum strongly emarginate posteriorly (Fig. 6C); the emargination reaches anteriorly the scutellar foveae. In lateral view, the posterior emargination of mesoscutellum appears as two rounded apically and slightly flat, curved upwards projections. In lateral view, the space between the mesoscutellar projections and the posterior limit of mesoscutellum is high. Axillula large, deep, heavily pubescent, with distinct margins. Mesoscutellum in lateral view with the posterodorsal extension of body of subaxillular strip long, nearly reaching upper margin of mesoscutellum. Mesopleuron coarsely reticulate rugose, the rugae not as strong as in mesoscutum.

Metanotum. Metapectal-propodeal complex. Metapleural sulcus obscured by the strong sculpture. Metascutellum weakly rugose; metanotal trough deep, smooth and pubescent. Median propodeal area with strong and coarse reticulate rugae; densely pubescent; lateral propodeal carinae distinct, subparallel anteriorly and converging posteriorly.

Legs. Densely pubescent; femora and tibiae robust. Femur 4× as long as wide; metatibia 1.6× as long as metatarsus; apical margin of metatarsomeres 1–4, with long strong erect setae. Metatarsal claws with strong triangular basal lobes or teeth.

Forewing (Fig. 8C), about 1.2× as long as body, radial cell 3.7× as long as wide; open along anterior margin; areolet very small, but visible. All veins heavily infuscate. M and Cu1 veins nearly straight, not reaching wing margin. Rs+M reaching basalis, well-marked. First abscissa of radius (2r) slightly angled, not projected. Cu1 vein not branched in two veins. Apical margin with very short or obsolete hair fringe.

Metasoma (Fig. 7D), in lateral view 1.3× as long as high. Second metasomal tergite covering about 0.6× length of metasoma. Anterior 2/3 smooth and shining; posterior one third with a band of micropunctures clearly visible; the punctate sculpture extended on subsequent tergites; ventral area of second metasomal tergite moderately pubescent, with a relatively dense patch of setae. Projecting part of hypopygial spine moderately long (Fig. 7D); about 5× as long as high in lateral view; laterally with long setae, longer than spine width, but not forming an apical tuft.

Male (Figs 6B, 7A, E, 8B, D). Differs from the female as follows: smaller size, length 5.7 mm on average (n = 3). Body and wings almost completely black, except the mandibles, metasoma ventrally, tarsomeres of legs and half of the apical flagellomeres of antennae which are more or less reddish (Fig. 8B). Antennae, legs and wings relatively longer. Antenna with 14 segments (Fig. 7A). Antennal formula (mean of four measured individuals) as: 0.29(0.18):0.15(0.16):0.69(0.16):0.46(0.15):0.40(0.15): 0.41(0.15):0.38(0.14):0.36(0.14):0.34(0.14):0.34(0.14):0.31(0.14):0.32(0.13):0.29(0.12):0.25(0.11):0.23(0.11). F1 slightly curved, weakly enlarged apically and flattened ventrally, 1.5× as long as F2; placodeal sensilla present in all the flagellomeres. Head 1.3× as wide as high; apical part of gena slightly expanded. Frontal pit distinct, prolonged by a groove towards median ocellus. Pair of frontal longitudinal carinae more convergent towards epistomal line (Fig. 6B). Projection of anterior margin of clypeus more incised. Forewing (Fig. 8D) relatively longer 1.3× as long as body. Almost completely black, except the distal transversal clear band that is much smaller and less extended.

(Fig. 8E, F). The gall is similar to the gall of Amphibolips dampfi described by Kinsey (1937). A moderate to large “oak apple”, irregularly spherical gall with spongy inner consistency. Some are slightly elongated towards the apex. The surface is slightly rough when intact, but may have more pronounced irregularities, which cause deformations on the surface or in the general shape. Monothalamic. They are light green without spots when they are fresh and light brown when they are dry. The epidermis is thin, at 0.4 mm thick; firmly attached to the internal spongy tissue when fresh; firm and brittle when dry. The consistency is relatively hard and fleshy when green and brittle when dry. Internally, the spongy tissue occupies the entire space between the epidermis and the larval chamber (Fig. 8F). Diameter of 30 mm and height of 31 mm on average (diameter of 16 to 44 mm and height of 18 to 51 mm; n = 18). Rigid and oval larval cell, 0.4 mm thick and 6.5 mm long × 5 mm in diameter on average (n = 2). Galls are formed on the twigs of Quercus zempoaltepecana Trel. Galls are relatively common in the study area.

Known only from the type locality along the route from Ixtlán to Tepanzacoalcos (Oaxaca State, Mexico).

Sexual generation. The galls were collected in late April and the insects emerged shortly thereafter, in early May. It is normal to find galls deformed and/or attacked by inquilines and parasitoids; the deformed or attacked galls are usually relatively small.

Holotype: 1♀ in the Museo Nacional de Ciencias Naturales (MNCN), Madrid, Spain, mounted (glued) on a card. Mexico, Veracruz, Xico, in the Texolo waterfall, 19°24.11'N, 96°59.69'W, ca. 1170 m alt., ex gall Quercus sapotifolia Liebm. Collected 27/04/2008; emerged 04/2008. Nieves-Aldrey & Pascual leg.

Named after the smoky black forewing.

Amphibolips nigrialatus is closely allied to A. dampfi Kinsey, 1937 and the new species Amphibolips kinseyi. Despite being based on a single female holotype, we found distinctive diagnostic characters that let us describe the specimen as belonging to a new species. The strongly-emarginate mesoscutellum relates the new species to A. kinseyi and A. dampfi, but in A. nigrialatus, the postero-lateral projections of the scutellum are pointed apically and curved upwards. Moreover, the scutellar foveae are very large in the new species, extending approximately one half of the length of the mesoscutellum, medially confluent and not separated by a carina or groove, while they are well separated by the mesoscutellar impression in the other two species. The forewing colour of A. nigrialatus is the darkest we have seen in females of Amphibolips species from Mexico and the black smoky colouration even extends to the costal and basal cells and below the cubital vein. In this last character, it resembles A. castroviejoi from Panama, but in this late species, the forewing area anterior to the transversal band is even darker (Fig. 15F), besides other distinguishing characters given in the identification key (transversal clear band larger, smooth scutellar foveae and visible notauli). The clear transversal band in the discoidal cell of forewing is very short and narrow in A. nigrialatus, measuring not more than one-fifth of the length of the radial cell (Fig. 13A), while in A. kinseyi, it is wider, measuring at least one-half the length of the radial cell (Fig. 8C). Additionally, the green spherical gall of the new species (A. nigrialatus) on Quercus sapotifolia is distinguishable from the galls of A. dampfi and A. kinseyi on Q. ocoteifolia Liebm. and Q. zempoaltepecana Trel., respectively.

Body length: 6.6 mm (n = 1) for the female.

Female. (Fig. 13B). Body almost completely black with the exception of the mandibles, the antennae apically, the metasoma ventrally, especially the hypopygium and parts of the legs, including the tarsi, which are reddish. Forewing predominantly black infuscate, except a large basal area delimited by the medial and cubital veins and another smaller area above the medial vein. A small clear transversal band, that starts below the radial cell and extends towards the medial vein, but does not reach the cubital vein, is present (Fig. 13A).

Head, in dorsal view (Fig. 10A) 2.2× as wide as long; narrower than mesosoma. OOL 1.4× POL 0.7× DOL; posterior ocelli separated from internal orbit of an eye by 2.2× its diameter. Head in anterior view (Fig. 11A) 1.3× as broad as high; gena slightly broadened behind eyes. Vertex, frons, lower face and gena, with coarse reticulate-rugose sculpture. Face with two longitudinal carinae, extending from ventral margin of toruli to converge towards the anterior tentorial pits; irradiating carinae from clypeus indistinct or absent; head moderately pubescent, except in vertex and frons. Clypeus more or less hexagonal, ventral margin strongly projecting over mandibles and moderately incised or sinuate on anterior margin. Anterior tentorial pits well visible; epistomal sulcus and clypeo-pleurostomal lines also distinct. Malar space 0.8× height of a compound eye. Toruli situated about mid-height of compound eye; transfacial line 1.7× height of an eye; distance between antennal rim and compound eye almost equal to the width of antennal socket including rim. Ocellar plate slightly raised.

Mouthparts (Fig. 11A), mandibles strong, exposed, with dense setae in base, right mandible with three teeth, left with two teeth.

Antenna (Fig. 10B), 0.6× as long as body length; with 13 antennomeres; 12 and 13 incompletely separated (Fig. 10C). Flagellum not broadening towards apex; with relatively long, erect setae. Antennal formula : 0.4(0.22):0.16(0.18):0.58(0.18):0.36(0.18):0.32(0.18):0.28(0.18):0.26(0.18):0.24(0.18): 0.23(0.18):0.2(0.18):0.2(0.18):0.18(0.18):0.34(0.16). Pedicel, short, 0.4× as long as scape and slightly broader than long. F1 1.6× as long as F2; F8–F10 as long as wide, F11 2.1× times as long as wide, 1.9× as long as F10. Placodeal sensilla present on flagellomeres F3–F11, disposed in dense rows of 8–10 sensilla, only in half dorsal area of each flagellomere.

Mesosoma in lateral view 1.1× as long as high. Pronotum, moderately pubescent; lateral surface of pronotum with strong irregular reticulate rugose sculpture (Fig. 11B). Pronotum medially short; ratio of length of pronotum medially/laterally = 0.23. Pronotal plate indistinct.

Mesonotum. Mesoscutum (Fig. 10A) barely pubescent and with strong coarse reticulate sculpture, the interspaces smooth and shining. Notauli indistinct, obscured by the coarse sculpture; more so in anterior one third of mesoscutum; longitudinal median impression indistinct. Anteroadmedian signa and parapsidal signa distinct. Transscutal fissure very narrow, sinuate. Mesoscutellum as long as wide; about 0.5× as long as mesoscutum. Scutellar foveae rounded transverse, about 0.5× as long as mesoscutellum, the scutellar foveae are confluent and not separated medially by a carina or groove; some transverse strong rugae visible with smooth and shining intervals. Mesoscutellum strongly coarsely rugose, with a deep and broad median longitudinal impression which makes the mesoscutellum strongly emarginate posteriorly (Fig. 10A); the emargination not reaching anteriorly the scutellar foveae. Postero-lateral projections of scutellum pointed apically and curved upwards (Fig. 11C, D). Mesopleuron coarsely reticulate rugose, the rugae not as strong as in mesoscutum (Fig. 11B). Mesoscutellum in lateral view with the posterodorsal extension of body of subaxillular strip short, not reaching one half of mesoscutellar upper margin.

Metanotum. Metapectal-propodeal complex. Metapleural sulcus distinct, reaching posterior margin of mesopectus at about mid-height of metapectal-propodeal complex. Metascutellum rugose; metanotal trough deep, smooth and pubescent. Median propodeal area with strong and coarse reticulate rugae; densely pubescent; lateral propodeal carinae distinct, subparallel anteriorly and converging posteriorly (Fig. 11E).

Legs. Densely pubescent; femora and tibiae robust. Metatibia about 1.7× as long as metatarsus. Metatarsal claws with strong triangular basal lobes or teeth (Fig. 12C).

Forewing (Fig. 13A), about 1.1× as long as body, radial cell 3.9× as long as wide; open along anterior margin; areolet absent. All veins heavily infuscate. M and Cu1 veins nearly straight, not reaching wing margin. Rs+M complete, reaching basalis. First abscissa of radius (2r) slightly angled, not projected into the radial cell. The two branches of the cubitalis vein are not interrupted by a gap. Apical margin with very short hair fringe.

Metasoma (Fig. 12A) in dorsal view 1.5× as long as wide; in lateral view 1.2× as long as high (Fig. 11F). Second metasomal tergite covering about 0.64× the length of metasoma. In dorsal view, anterior half of T2 smooth and somewhat shining, posterior half with two types of microsculpture clearly visible, first a series of slightly hexagonal cells and in the back micropunctures, both microstructures occupying the same proportion (Fig. 12B). In lateral view, anterior 2/3 smooth and somewhat shining; posterior one third with a band of micropunctures clearly visible. The punctate sculpture extended on subsequent tergites. Ventral area of second metasomal tergite moderately pubescent, with a relatively dense patch of setae. Projecting part of hypopygial spine long (Fig. 12D); about 6.3× as long as high in lateral view; laterally with long setae, longer than spine width, but not forming an apical tuft.

Male. Unknown.

(Fig. 13C). A regular, spherical, moderately-sized gall with a green colour when it is fresh. When dry, the gall acquires a rough and slightly elongated appearance and turns brown in colour. The galls measure on average 16.5 × 21.5 mm (diameter of 14 to 19 mm and length of 17 to 25 mm; n = 4). The gall is monothalamic. The outer shell is thin, flexible and of fleshy consistency when fresh and becomes rigid and hardly detachable from the parenchyma when dry. Internally, there is a spherical larval cell in the centre of the gall (5 × 5 mm; n = 1); a spongy tissue occupies the entire space between the epidermis and the larval chamber and is hardly separable from the larval chamber. When it is dry, the gall is moderately fragile.

On twigs of Quercus sapotifolia Liebm. Closely resembles that of Amphibolips oaxacae Nieves-Aldrey & Pascual, 2012, A. michoacaensis Nieves-Aldrey y Maldonado, 2012, A. trizonata Ashmead, 1896 and Amphibolips kinseyi sp. nov. However, the gall of A. nigrialatus differs in its size, which is approximately half that of the other species. The gall is similar to that of A. murata Weld, 1957, but not as rough when dry and to that of A. quercusfuliginosa Ashmead, 1885, from which it is impossible to differentiate according to the original description of the gall. Nonetheless, the adults are completely different.

Known only from the type locality in Veracruz State, Mexico.

Presumably, a sexual generation. The gall was collected in late April and the insect emerged shortly afterwards.