Chilaspis Mayr, 1881

Melika, George, Pujade-Villar, Juli, Abe, Yoshihisa, Tang, Chang-Ti, Nicholls, James, Wachi, Nakatada, Ide, Tatsuya, Yang, Man-Miao, Pénzes, Zsolt, Csóka, György & Stone, Graham N., 2010, 2470, Zootaxa 2470, pp. 1-79 : 30

Chilaspis Mayr, 1881 , stat. rev.

Figs 200–206.

Type species: Andricus nitidus Giraud, 1859 . Designated by Mayr (1881).

Diagnosis. Chilaspis closely resembles the two genera Plagiotrochus and Dryocosmus . However, it differs from the first by a smooth mesoscutum and mesopleuron and differs from Dryocosmus by the characters given in the generic key. One Dryocosmus species in particular, D. caspiensis , described from Iran ( Tavakoli et al. 2008) and known from the asexual generation only, very closely resembles Chilaspis in its morphology and coexists with it in the same localities and even on the same trees of Q. castaneifolia in different localities in Iran. However, in asexual female Chilaspis , the pedicel and scape are not broadened, only slightly or not broader than flagellomeres, all flagellomeres nearly of the same width; the mesoscutellum with wrinkles and rugae along lateral and posterior sides, while in D. caspiensis the pedicel and scape are very strongly broadened, at least 2.2–2.5 times broader than flagellomeres; flagellomeres broadened towards the apex, F8–F12 at least 2.0 times as broad as the first flagellomeres; the mesoscutellum with narrow strip of wrinkles and rugae along lateral and posterior sides.

Both Cynips L. and Biorhiza Westwood , resemble Chilaspis in having smooth mesoscutum and mesopleuron, but they have a complete malar sulcus, and the malar space lack striae, and are not associated with section Cerris oaks. More details are provided in Pujade-Villar et al. (2003).

Redescription. Body uniformly yellow or light brown. Surface sculpture absent or very weak, alutaceous or delicately coriaceous on some structures. Head transverse, broader than high, gena broadened behind eye, well-visible in anterior view; malar sulcus absent, malar space with very few indistinct and weak striae radiating from clypeus but never reaching eye margin and antennal sockets; vertex and occiput smooth or very delicately coriaceous. Compound eye, both in females and males, small, transfacial distance smaller or almost equal to height of eye. Antenna in asexual female with 11 – 12 flagellomeres, in sexual female – 12 – 13 flagellomeres, in male with 13 – 14 flagellomeres. Pedicel and scape not broadened, only slightly or not broader than flagellomeres, all flagellomeres of nearly same width. The head, mesoscutum and mesopleuron smooth and shiny; notaulus deep, complete, reaching pronotum; mesoscutellum delimited marginally by distinct sharp carina, smooth or with very weak, delicate sculpture; scutellar foveae distinct, with smooth, shiny or very delicately sculptured bottom, separated by more or less distinct median (central) carina; propodeum with two distinct propodeal carinae, laterally curved outwards delimiting smooth or delicately sculptured central area; metasoma strongly compressed laterally; ventral spine of hypopygium short, with sparse white setae reaching behind apex of spine.

Comments. The genus is represented by two Western Palaearctic species, Chilaspis nitida (Giraud) , comb. rev. distributed in Europe, on Q. cerris L. and C. israeli (Sternlicht) , comb. rev. known from the Middle East into Iran, on Quercus castaneifolia C.A.Mey , Q. brantii Lindl. and Q. libani Olivier ( Tavakoli et al. 2008) . In recent phylogenetic reconstructions, C. nitida and C. israeli form a strongly-supported monophyletic clade with Plagiotrochus as a well-supported sister group, and well removed from other Dryocosmus ( Stone et al. 2009; Fig.1). The earlier synonymization of Chilaspis to Dryocosmus was premature and did not adequately incorporate molecular or morphological character states in Aphelonyx , Pseudoneuroterus , Neuroterus and Cerroneuroterus ( Ács et al. 2007) . Examination of the species tree in Ács et al. (2007, their Fig. 3) shows their synonymization to be based on the fact that Chilaspis and Dryocosmus species are intermingled, with D. kuriphilus as a basal sister group. Later analyses that had other section Cerris-galling genera been included, show they should be not synonymised to Dryocosmus . Analyses of morphological character states in different “ Dryocosmus ” species were inadequately detailed, and a “lumper” approach was used -- the synonymization was based on two main characters: i) the absence of a surface sculpture on the mesoscutum and mesoscutellum, and ii) the short projecting part of the ventral spine of the hypopygium, without taking into account other important characters which are given in the diagnosis to Chilaspis and in the generic key above.