Nichollsiella Melika, Pujade-Villar & 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 : 32-35

Nichollsiella Melika, Pujade-Villar & Stone , gen. nov.

Figs 97–141

urn:lsid:zoobank.org:act:E730D087-6417-43CF-A61B-5C3C37E0DB31

Type species. Cynips sulcatus Ashmead, 1896: 123 , female, gall.

Etymology. Named after J.A. Nicholls for his outstanding work on oak gall wasps ( Cynipidae : Cynipini ).

Gender. Masculine.

Diagnosis. Only asexual females are known. Morphologically similar to the Central American genus Coffeikokkos Pujade-Villar & Melika and Barucynips Medianero & Nieves-Aldrey , although material from these genera was not available for the phylogenetic reconstruction ( Fig. 233 ). In Coffeikkokos asexual female antenna has 14–15 flagellomeres, the clypeus is small, rounded, not emarginate ventrally; tarsal claws are simple, without a basal lobe; the lateral propodeal carina is incomplete, not reaching the nucha; second metasomal tergite has a few white setae anterolaterally; all terga smooth, glabrous, without setae; the prominent part of the ventral spine of the hypopygium 2.5x as long as broad. In Nichollsiella the antenna has 13–14 flagellomeres, tarsal claws with a basal lobe; the lateral propodeal carina is complete, reaching the nucha; second metasomal tergum striate, with dense setae laterally, all terga with dense setae laterally, reticulate posteriorly; the prominent part of the ventral spine of the hypopygium as long as broad. In Barucynips the antenna has 14 flagellomeres, the prominent part of the ventral spine of the hypopygium lanceolate and long, at least 4.0x as long as broad; all terga smooth, glabrous. In Coffeikkokos asexual female antenna has 14–15 flagellomeres, the clypeus is small, rounded, not emarginate ventrally; tarsal claws are simple, without a basal lobe; the lateral propodeal carina is incomplete, not reaching the nucha; second metasomal tergum has a few white setae anterolaterally; all terga smooth, glabrous, without setae; the prominent part of the ventral spine of the hypopygium 2.5x as long as broad. In Nichollsiella the antenna has 13–14 flagellomeres, tarsal claws with a basal lobe; the lateral propodeal carina is complete, reaching the nucha; second metasomal tergum striate, with dense setae laterally, all terga with dense setae laterally, reticulate posteriorly; the prominent part of the ventral spine of the hypopygium as long as broad.

Also resembles Striatoandricus Pujade-Villar ( Cuesta-Porta et al. 2020). In both genera the asexual females have the gena slightly broadened behind the eye, and the metasoma is striate and/or reticulate. However, in Striatoandricus the mesoscutum is coriaceous, notaulus complete or incomplete, the mesopleuron alutaceous, the nucha dorsally and laterally sulcate, the metasoma with only a few setae laterally on second metasomal tergum, the prominent part of the ventral spine of the hypopygium usually 2.0–4.0x as long as broad, with sparse setae which never form a tuft beyond the apex. In Nichollsiella the mesoscutum smooth, glabrous to alutaceous, notaulus incomplete, the mesopleuron reticulate, the nucha dorsally smooth, glabrous, with sulci (or rugae) only laterally; the metasoma covered with dense white setae; the prominent part of the ventral spine of the hypopygium short, as long as broad.

Nichollsiella also resembles Kokkocynips in having a transverse or rounded head in frontal view, with striate/ reticulate metasomal terga. In Kokkocynips the second metasomal tergum has sparse lateral setae, subsequent terga without setae, tarsal claws are simple, the prominent part of the ventral spine of the hypopygium 3.0–3.3x as long as broad, while in Nichollsiella the second metasomal tergum and subsequent terga have dense lateral setae, tarsal claws with acute basal lobes, the prominent part of the ventral spine of the hypopygium is short, as long as broad, with long setae extending far beyond apex of spine.

Nichollsiella resembles Kinseyella in having usually dense setae on the head and metasoma, incomplete notauli, ventral spine of hypopygium short and broad distally with setae forming a tuft beyond the apex. However, in Nichollsiella the head and mesoscutum are strongly reticulate and mesoscutum uniformly densely pubescent or almost smooth with strong pileferous points, lateral propodeal carinae are present, rarely incomplete, if incomplete then the central propodeal area with sculpturing differing from that on lateral propodeal area, second metasomal tergum more or less striate in anterior 2/3, while in Kinseyella head and mesoscutum coriaceous, never with piliferous points, mesoscutum with dense setae on lateral margins, around notauli and between anterior parallel lines, lateral propodeal carinae absent or very indistinct, central propodeal area with the same sculpturing as laterally, second metasomal tergum smooth or reticulate in anterior 2/3.

Nichollsiella resembles Disholcaspis by having dense setae on the head, mesosoma and the second metasomal tergum, incomplete notaulus, and reticulate mesoscutum and mesopleuron. However, in Nichollsiella the second metasomal tergum is dorsally delicately striate/reticulate, all terga pubescent and the ventral spine of the hypopygium is broad distally with setae that form a tuft beyond the apex, while in Disholcaspis all terga are micropunctuate, never dorsally striate or reticulate, T3 and subsequent terga are bare, the ventral spine of the hypopygium is needle-like, without a tuft of setae or with a very inconspicuous tuft.

Nichollsiella most closely resembles Burnettweldia given the short broad ventral spine of the hypopygium with setae forming a tuft, and all terga having dense setae laterally. However, in Nichollsiella the second metasomal tergum is delicately striate or reticulate dorsally, while in Burnettweldia all terga are micropunctate, never striate or reticulate.

Nichollsiella resembles Disholandricus by the short prominent part of the ventral spine of the hypopygium; however, in Nichollsiella the second metasomal tergum is striate or reticulate, and all terga with dense white setae laterally, while in Disholandricus the second metasomal tergum is smooth, with sparse white setae anterolaterally, and all subsequent terga are bare, without setae.

Description. Asexual female. ( Figs 97–108 , 110–124 , 126–139 ). Head, mesosoma, mandibles, mouthparts, antennae, legs and metasoma uniformly reddish or rusty brown. In some species or specimens head around occipital foramen, two stripes along parapsidal lines and notauli, the propleura, central propodeal area, and ventral side of mesosoma dark brown to black.

Head rounded or transverse, reticulate, with white setae, 2.0–2.5x as broad as long from dorsal view; as broad as or slightly broader than high in frontal view and slightly narrower than mesosoma. Gena reticulate, not broadened or slightly broadened behind eye in frontal view; in lateral view as broad as transverse diameter of eye in dorsal part and narrower or broader than transverse diameter of eye in ventral part. Malar space reticulate, with few delicate striae radiating from clypeus and not reaching eye, malar sulcus absent; eye 2–3x as high as length of malar space. Inner margins of eyes parallel. POL 1.5–2.2x as long as OOL; OOL 1.1–1.5x as long as diameter of lateral ocellus, equal to or slightly longer or shorter than LOL; ocelli ovate or posterior ocelli rounded, all three equal in size. Transfacial distance nearly equal to height of eye; 1.3–1.4x as long as height of lower face (distance between antennal rim and ventral margin of clypeus), toruli located level with the upper half of compound eye; diameter of antennal torulus 2.0–3.0x as long as distance between them, distance between torulus and eye margin equal to diameter of torulus. Lower face coriaceous to reticulate, without striae but with dense setae, with slightly elevated reticulate median area. Clypeus rectangular to quadrangular, flat, reticulate to smooth, glabrous, with deep anterior tentorial pits, distinct epistomal sulcus and clypeo-pleurostomal line; ventrally rounded, emarginate, not incised medially. Frons, interocellar area, vertex, occiput, postgena, and postocciput around occipital foramen all reticulate or alutaceous, with dense white setae; posterior tentorial pits large, deep, elongate; height of oral foramen as high or slightly shorter than height of postgenal bridge+occipital foramen; occipital foramen slightly higher or equal to height of postgenal bridge; hypostomal carina emarginate, continuing into postgenal sulcus; postgenal sulci bent outwards anteriorly; postgenal bridge smooth, glabrous, anteriorly diverging, as broad as width of occipital foramen. Antenna as long as or slightly longer than head+mesosoma, with 13–14 flagellomeres, pedicel slightly longer or as broad as high, F1 always longer than F2, F2 to F6 gradually shorter, subsequent flagellomeres nearly equal in length, last flagellomere always longer than the previous one.

Mesosoma longer than high in lateral view. Pronotum smooth, glabrous, alutaceous or delicately coriaceous, with dense white setae, without or with very delicate striae laterally, emarginate and foveolate along lateral edge; propleuron smooth or delicately transversally striate, glabrous, with dense white setae. Mesoscutum uniformly reticulate with dense white setae or smooth, glabrous to alutaceous, with distinct deep punctures; nearly as long as broad (width measured across base of tegulae). Notauli incomplete, extending to 3/4 to 1/2 of mesoscutum length, converging posteriorly. Anterior parallel lines extending to half-length of mesoscutum, in the form of smooth stripes; parapsidal line indicated by delicately reticulate or smooth, glabrous stripe, extending to half-length of mesoscutum; median mesoscutal line absent or present; parascutal carina narrow, reaching pronotum. Transscutal articulation deep, distinct. Mesoscutellum rounded, as long as broad; shorter than mesoscutum, uniformly rugose, overhanging metanotum; mesoscutellar foveae rounded to transverse, with smooth, glabrous bottom, divided by narrow triangular slightly elevated central carina or absent, indicated by more impressed anterior part of mesoscutellum disk. Mesopleuron, including speculum, alutaceous to uniformly reticulate (in same cases speculum smooth), with white setae; mesopleural triangle with dense white setae that hide surface sculpture. Metapleural sulcus distinct, reaching mesopleuron slightly above half of its height, upper part of sulcus indistinct or distinct; dorsal and lateral axillar areas smooth to delicately coriaceous, with dense setae; axillar carina broad, with longitudinal striae; subaxillular bar smooth, glabrous, triangular, at its most posterior end slightly higher than height of metanotal trough. Metascutellum reticulate or coriaceous, higher than height of smooth, glabrous ventral impressed area; metanotal trough smooth, glabrous, with or without setae. Lateral propodeal carinae complete, incomplete or absent; central propodeal area darker than rest of propodeum, smooth, glabrous, with few rugae, without setae; lateral propodeal area delicately coriaceous, with dense white setae; nucha short, smooth, glabrous dorsally, with delicate lateral longitudinal sulci or delicately coriaceous. Tarsal claws with acute basal lobe.

Forewing longer than body, with distinct dark brown veins, margin with cilia; radial cell opened, 3.0-4.1 as long as broad, R1 and Rs either reaching or not reaching wing margin; areolet triangular, well-delimited by distinct brown veins; Rs+M distinct, reaching basalis around its mid-height.

Metasoma as long as or longer than head+mesosoma, higher or slightly shorter than long in lateral view; second metasomal tergum extending to 3/4 of metasoma length, striate dorsally and laterally on anterior 2/3 of tergum 2, reticulate distally, with dense setae; all subsequent terga and hypopygium reticulate, with dense white setae; prominent part of ventral spine of hypopygium short, as long as broad or slightly longer than broad, with parallel sides, dense white long setae extending far beyond apex of spine and forming a tuft. Body length 3.3–5.0 mm.

Three species are known: N. arizonica (Cockerell) , comb. nov., N. puigi Melika, Cuesta-Porta & Pujade-Villar , sp. nov. and N. sulcata (Ashmead) , comb. nov.

Key to the Nichollsiella species

1. Head transverse in frontal view, gena broadened behind eye in frontal view, ocelli strongly elevated above vertex ( Figs 110– 113 ); median mesoscutal line present at least posteriorly ( Figs 117–118 ); antenna with 14 flagellomeres ( Fig. 114 )............................................................................................... N. puigi sp. nov.

- Head rounded in frontal view, gena not or slightly broadened behind eye, ocelli not or weakly elevated ( Figs 97–100 , 126–129 ); median mesoscutal line absent ( Figs 104–105 , 133–134 ); antenna with 13 flagellomeres ( Figs 101 , 130 )................ 2

2. Mesoscutum smooth, with scattered setae and piliferous points ( Figs 104–105 ); speculum smooth ( Fig. 103 ); lateral propodeal carinae incomplete or absent ( Fig. 106 ); radial cell of forewing around 4.0x as long as broad; nucha without sulci dorsally ( Fig. 106 ), second metasomal tergum smooth in anterior 2/3 and reticulate in posterior 1/3 with carinae dorsolaterally ( Figs 107–108 )........................................................................ N. arizonica comb. nov.

- Mesoscutum uniformly reticulate, with dense setae and inconspicuous piliferous points ( Figs 133–134 ); speculum uniformly reticulate ( Fig. 132 ); lateral propodeal carinae complete ( Fig. 135 ); radial cell of forewing around 3.0x as long as broad ( Fig. 136 ); nucha with sulci dorsally ( Fig. 135 ); second metasomal tergum with longitudinal parallel sulci dorsally, reticulate in posterior 2/3, smooth, glabrous in anterior 1/3 ( Figs 137–139 )................................ N. sulcata comb. nov.

Figures

FIGURE 233. Consensus tree showing the relationships among the three new Nearctic gall wasp genera Burnettweldia, Nichollsiella and Disholandricus, the re-established genus Paracraspis and other allied genera, based on a Bayesian analysis of a concatenation of three loci (cytochrome b, long-wavelength opsin, and the D2 region of the 28S rRNA gene). Numbers above nodes indicate posterior probability support; nodes with <70% support have been collapsed.

FIGURES 97–102. Nichollsiella arizonica, comb. nov., asexual female. 97–100, head: 97, frontal view, 98, dorsal view, 99, lateral view, 100, posterior view. 101, antenna. 102, mesosoma and propleura, frontal view.

FIGURES 103–106. Nichollsiella arizonica, comb. nov., asexual female. 103, mesosoma, lateral view. 104, mesoscutum, dorsal view. 105, mesoscutellum, dorsal view. 106, metascutellum and propodeum, posterodorsal view.

FIGURES 107–109. Nichollsiella arizonica, comb. nov., asexual female. 107–108, metasoma: 107, lateral view, 108, dorsal view, part. 109, asexual galls.

FIGURES 110–115. Nichollsiella puigi, sp. nov., asexual female. 110–113, head: 110, frontal view, 111, dorsal view, 112, lateral view, 113, posterior view. 114, antenna. 115, mesosoma and propleura, frontal view.

FIGURES 116–119. Nichollsiella puigi, sp. nov., asexual female. 116, mesosoma, lateral view. 117, mesoscutum, dorsal view. 118, mesoscutellum, dorsal view. 119, metascutellum and propodeum, posterodorsal view.

FIGURES 120–124. Nichollsiella puigi, sp. nov., asexual female. 120, forewing. 121, hindleg. 122–124, metasoma: 122, lateral view, 123, ventral view, 124, dorsal view.

FIGURE 125. Nichollsiella puigi, sp. nov., asexual galls.

FIGURES 126–131. Nichollsiella sulcata, comb. nov., asexual female. 126–129, head: 126, frontal view, 127, dorsal view, 128, lateral view, 129, posterior view. 130, antenna. 131, mesosoma and propleura, frontal view.

FIGURES 132–135. Nichollsiella sulcata, comb. nov., asexual female. 132, mesosoma, lateral view. 133, mesoscutum, dorsal view. 134, mesoscutellum, dorsal view. 135, metascutellum and propodeum, posterodorsal view.

FIGURES 136–139. Nichollsiella sulcata, comb. nov., asexual female. 136, forewing. 137–139, metasoma: 137, lateral view, 138, dorsal view, 139, ventral view.

FIGURES 140–141. Nichollsiella sulcata, comb. nov., asexual galls. 140, young growing galls. 141, mature galls.