Andricus mellificus Nicholls, Stone & Melika, 2021

Melika, George, Nicholls, James A., Abrahamson, Warren G., Buss, Eileen A. & Stone, Graham N., 2021, New species of Nearctic oak gall wasps (Hymenoptera: Cynipidae, Cynipini), Zootaxa 5084 (1), pp. 1-131 : 46-49

Andricus mellificus Nicholls, Stone & Melika , sp. nov.

Figs. 159–171

urn:lsid:zoobank.org:act:FA848B4B-F890-4807-A424-7D9C7D50A190

Type material: HOLOTYPE female “ USA, Arizona, Chiricahua Mnts nr Portal. Leg. J. Nicholls. 2008.04.06. Code AZ1973, spAZb7; ex Quercus arizonica ” . PARATYPES: 2 females with the same labels as the holotype. The holotype is deposited at the USNM , 2 female at the PHDNRL .

Etymology. Named after the behavior of this species in inducing galls that secrete nectar.

Diagnosis. The gall is very distinctive; no other species from Arizona are known to induce such a specifically shaped and coloured gall ( Fig. 171 ).

Description. Female ( Figs. 159–170 ). Head, mesosoma black, metasoma dark brown, antennae, mouthparts, tegulae, legs brown.

Head delicately coriaceous, with sparse white setae, denser on lower face; rounded, only slightly broader than high and slightly broader than mesosoma in frontal view, 1.9× as broad as long in dorsal view. Gena coriaceous, slightly broadened behind eye in frontal view, narrower than transverse diameter of eye in lateral view. Malar space delicately coriaceous, glabrous, with a few delicate striae radiating from clypeus and not reaching eye; eye 2.9× as high as length of malar space. Eyes slightly converging ventrally. POL 2.1× as long as OOL; OOL 1.3× as long as diameter of lateral ocellus and equal to LOL; lateral ocelli slightly larger than central ocellus. Transfacial distance as long as height of eye; diameter of antennal torulus 1.8× as long as distance between them, distance between torulus and eye 1.3× as long as diameter of torulus; lower face coriaceous, with white long setae, without striae; slightly elevated median area coriaceous. Clypeus trapezoid, slightly broader than high, smooth, glabrous, with a few long setae; ventrally rounded, not emarginate and without median incision; anterior tentorial pit small, rounded, epistomal sulcus and clypeo-pleurostomal line distinct. Frons uniformly and delicately coriaceous, without striae; interocellar area delicately coriaceous and slightly elevated. Vertex delicately coriaceous; occiput with delicate transverse parallel rugae; postocciput smooth, glabrous; postgena coriaceous, with white setae; posterior tentorial pit large, ovate, area below impressed; occipital foramen higher than height of postgenal bridge; hypostomal carina emarginate, continuing into postgenal sulci which diverge towards occipital foramen, postgenal bridge anteriorly broader. Antenna longer than head+mesosoma, with 12 flagellomeres (in some paratypes suture between F12 and F11 indistinct), pedicel slightly longer than broad, all flagellomeres slightly broadened towards apex, F1 1.3× as long as pedicel and equal in length to F2, F2 slightly longer than F3, F3=F4, F5–F7 equal in length, F7–F12 shorter than preceding flagellomeres and equal in length, placodeal sensilla on F4–F12.

Mesosoma longer than high, with sparse short white setae. Pronotum smooth, glabrous dorsally; coriaceous, with net of delicate striae laterally; propleuron with delicate transverse striae, glabrous. Mesoscutum reticulate in posterior 2/3, with more transversely orientated striae in anterior 1/3, with sparse white setae, denser along lateral and anterior sides; slightly longer than broad (greatest width measured across mesoscutum at level of base of tegulae). Notaulus complete, reaching pronotum; deeper and broader, with smooth glabrous bottom in posterior 2/3, less impressed but still distinct in anterior 1/3 of mesoscutum; posteriorly converging. Anterior parallel line visible in anterior 1/3 of mesoscutum, delimited by smooth surface; parapsidal line indistinct, hardly traceable; median mesoscutal line short; circumscutellar carina narrow, smooth, reaching notaulus. Mesoscutellum rounded, slightly longer than broad, posteriorly rounded, uniformly dull rugose, overhanging metanotum; mesoscutellar foveae separated by narrow elevated coriaceous central carina, ovate, broader than high, with smooth, glabrous bottom. Mesopleuron with delicate transverse striae at mid height, running across full length of mesopleuron; speculum smooth, glabrous; ventral part uniformly smooth, glabrous, without striae. Mesopleural triangle coriaceous; dorsal and lateral axillar areas alutaceous, glabrous, with some white short setae; subaxillular bar smooth, glabrous, most posterior part slightly narrower than height of metanotal trough; metapleural sulcus reaching mesopleuron in upper 1/3 of height, upper part of sulcus distinct. Metascutellum coriaceous, at least 3.0× as high as height of smooth, glabrous ventral impressed area; metanotal trough smooth, glabrous, with dense white setae; central propodeal area quadrangular, smooth, glabrous; lateral propodeal carinae parallel; lateral propodeal area smooth, glabrous, with long white setae. Nucha rugose, with strong irregular sulci. Tarsal claws with basal lobe.

Forewing longer than body, hyaline, margin without cilia, veins dark brown, radial cell open, 3.1× as long as broad, areolet triangular, distinct, Rs+M inconspicuous, its projection reaching basalis at mid height.

Metasoma as long as head+mesosoma, longer than high in lateral view; second metasomal tergite extending to 3/4 of metasoma length in dorsal view, with white setae anterolaterally; second and third tergites without micropunctures, fourth tergite with micropunctures. Hypopygium without micropunctures, prominent part of ventral spine of hypopygium 3.2× as long as broad in ventral view, narrowing towards apex, with some short setae ventrally which do not extend beyond apex of spine. Body length 2.1–2.3 mm (n = 3).

Gall ( Fig. 171 ). A small unilocular bud gall, reaching 4–5 mm in diameter, green at first then becoming redpurple, in an axillary bud. Gall ovoid with a flattened top and a central nipple; nectar-secreting. Also illustrated in Figure 24 of Weld (1960).

Biology. Only females are known, which induce small bud galls on Q. arizonica ; Weld (1960) also lists Q. rugosa as a host. Galls mature in April, and adults emerge soon afterwards. Although only females are known, the spring phenology of this gall strongly implies that this is a sexual generation and males remain to be discovered. This species was included under the species code spAZb 7 in the Nicholls et al. (2017) study of nectar secretion in oak gall wasps.

This gall was collected at several sites in Arizona, with DNA data used to confirm the morphological assessment that emerged individuals were conspecific. Two individuals were sequenced for cytb, differing by 1.62% (GenBank KX683628 , OK346276 ) .

Distribution. USA, Arizona: Chiricahua Mountains, Sonoita.

Figures

FIGURE 171. Andricus mellificus Nicholls, Stone & Melika, sp. nov., galls.

FIGURES 159–164. Andricus mellificus Nicholls, Stone & Melika, sp. nov., female: 159–162, head: 159, frontal view, 160, dorsal view, 161, lateral view, 162, posterior view. 163, antenna. 164, forewing, part.

FIGURES 165–170. Andricus mellificus Nicholls, Stone & Melika, sp. nov., female: 165, mesosoma and propleura, frontal view, 166, mesoscutum, dorsal view, 167, mesoscutellum, dorsal view, 168, mesosoma, lateral view, 169, metascutellum and propodeum, posterodorsal view, 170, metasoma, lateral view.

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