Cheiloneurus elegans (Dalman)

Hayat, Mohammad, Ahmad, Zubair & Khan, Farmanur Rehman, 2014, Encyrtidae (Hymenoptera: Chalcidoidea) from the Kingdom of Saudi Arabia, Zootaxa 3793 (1), pp. 1-59 : 24-26

Cheiloneurus elegans (Dalman)

( Figs 53–57 )

Encyrtus elegans Dalman, 1820: 151 , ♀. [lost]

Cheiloneurus elegans (Dalman) : Westwood, 1833: 343. Claridge, 1958: 157, ♀. Redescription. Trjapitzin, 1989: 308, key, citations, distribution, hosts. Trjapitzin & Triapitsyn, 2008: 472, key, citations, distribution, hosts.

This species is redescribed based on the specimens from Saudi Arabia . The reasons for the redescription of this supposedly well-known Palaearctic species are given under ‘Comments’.

Redescription. Female. Length, 1.30–1.56 mm. Frontovertex brownish yellow to brown; facial region brownish yellow to yellowish brown; malar space brownish yellow to brown. Mandible in about apical half brownish black. Antenna ( Fig. 53 ) with radicle pale brown; scape yellow, with base narrowly and dorsal and ventral margins brown; pedicel yellow, with base and dorsal margin brown; F1–F3 brownish yellow; F4 and F5 yellow; F6 at least in upper two-thirds to completely dark brown; clava with basal two segments dark brown, third segment brownish yellow. Mesosoma with pronotum dark brownish yellow; mesoscutum anterior three-fifths to two-thirds in middle half brownish yellow, sides and posterior third to two-fifths dark brown, hardly shiny; axilla pale brownish white; scutellum to level of posterior margins of axillae and apical third dark brownish yellow, middle half white; metanotum dark brown; tegula yellowish brown; mesopleuron brownish yellow; metapleuron brown to dark brown; propodeum yellow with brownish suffusions to completely dark brown. Fore wing ( Fig. 56 ) as in C. elegans -group of species; basal third, except a brownish streak at base, hyaline; rest of disc infuscate, with the usual hyaline areas, one smaller one adjacent to distal veins, and the other larger spot opposite; apex sometimes very narrowly hyaline. Hind wing hyaline. Fore leg with coxa white; femur, tibia and tarsus brownish yellow; last segment of tarsus pale brown. Mid leg with coxa brownish yellow; femur basal half white, distal half dark brownish yellow; tibia basal fourth or less white, remaining part brownish yellow with a dark brown patch at end of the white basal band; tarsus whitish yellow, last segment brown; spur white. Hind leg with coxa white; femur yellowish brown basally becoming brown apically with both margins dark brown; tibia with basal fourth or so white, rest of tibia pale brown to brownish yellow; tarsal segments white, last segment brown. Gaster colour variable; TI completely dark brown (with violet bronzy shine) to brown; sometimes with a narrow white crossband at base; TII–TVI brown to brownish yellow, and in one specimen pale brown with a large suboval dark brown patch in middle; TVII completely dark brown to white with a dark brown patch at apex; ovipositor sheaths brownish yellow, apex dark brown.

Head. Frontovertex width one-third of head width, and broader than distance between antennal toruli; ocellar triangle with apical angle a right angle to slightly acute triangle; head, in frontal view ( Fig. 54 ), very slightly broader than high; frontovertex and face with slightly raised, regular polygonal reticulate sculpture of small cells; setae on head white. Mandible as in Fig. 55 . Antenna ( Fig. 53 ) with scape about 4× as long as broad; pedicel slightly longer than F1 and F2 combined; F1 always slightly but distinctly longer than broad; F2 shorter than F1, and quadrate to slightly longer than broad; F3 slightly longer than broad to slightly broader than long, longer than F2 (one specimen) or subequal to F2 (one specimen), or shorter than F2 (3 specimens) (these relative lengths may vary in the two antennae of a single specimen); F1–F3 each smaller than F4; F4 slightly shorter than F5; F4 and F5 quadrate or each slightly longer than broad; F6 usually broader than long, but in one specimen, longer than broad; clava slightly longer than F4–F6 combined.

Mesosoma ( Fig. 57 ). Pronotum with slightly raised, transversely elongate reticulate sculpture; mesoscutum with fine, lineolate reticulate sculpture; scutellum with raised, polygonal reticulate sculpture, the cells slightly elongated; pronotum with pale brown setae; mesoscutum with silvery white setae with some brown setae in the brownish yellow area, and a pair of brown setae in middle of posterior margin; axilla with dark brown setae; scutellum, except apical half, with silvery white setae; scutellar brush setae dark brown to black; propodeum distal to spiracles with silvery white setae. Fore wing basal hyaline area nearly bare, but with a group of hyaline setae below parastigma; linea calva proximally with about 3 lines of dark brown setae, otherwise as in Fig. 56 .

Metasoma 1.28–1.55× as long as mesosoma; ovipositor at most very slightly exserted; ovipositor, as seen through the derm in slide mount, extends from base of gaster, and 1.63× as long as mid tibia; second valvifer 4.14× as long as third valvula; third valvula subequal in length to mid basitarsus.

Male. Unknown from Saudi Arabia .

Material examined. KSA: AL-BAHA: Qunfudah, i–iv.2011, (MT), Coll. S. Qahtani (6 ♀, two on slides, EH.1489 and EH.1680); Qunfudah, vi.2012, (MT), Coll. Z. Ahmad (2 ♀) ( ZDAMU).

Distribution. Palaearctic (several countries; Saudi Arabia : present record); Nearctic ( USA, Canada); Neotropical ( Mexico).

Comments. The above listed specimens run to C. elegans in the keys to species given by Trjapitzin (1989: p. 308, fig. 318, key couplet No. 21) and Trjapitzin & Triapitsyn (2008: p. 472, fig. 12, key couplet No. 10), and appear more or less similar to C. elegans elegantissimus De Santis (1964 : fig. 180) in having the mesoscutum anteriorly brownish yellow and posterior third or so and laterally dark brown. The specimen from west Europe have the mesoscutum completely dark brown ( Trjapitzin 1989: key couplet No. 26; Trjapitzin & Triapitsyn 2008: key couplet No. 20). The antenna illustrated by these authors has F1 longer than broad, F2 quadrate and shorter than F1, F3 subequal to or slightly longer than F2, F1–F3 each smaller than F4, and F6 slightly broader than long. Thus, in the dimensions of the funicle segments, the Saudi Arabian specimens agree with C. elegans . In two British specimens (gift by Noyes to ZDAMU) also F1–3 are smaller than F4, but the pedicel is shorter than F1 and F2 combined, and the mesoscutum is completely dark brown with metallic shine. The Saudi specimens may be considered as paler forms of C. elegans , and this would have settled the problem of identity of the Saudi Arabian specimens. However, the figure of the antenna given by Claridge (1958: fig. 3), whose study was based on a female from Richmond ( England) determined by Westwood, and further specimens from England and Germany, shows the pedicel shorter than F1 and F2 combined, F1–6 each being longer than broad and subequal in length, and the antenna described as ‘rufo-fuscous’. The description of body colour and of the antenna given by Claridge (1958) agree with the original description given by Dalman (1820: 151–152) and that given by Westwood (1833: 343). However, as the type of Encyrtus elegans Dalman is lost ( Claridge 1958), there is no way to check the dimensions of the funicle segments. I have, therefore, identified C. elegans on the basis of the figures of the antenna given by Trjapitzin (1989) and Trjapitzin & Triapitsyn (2008) and the description of C. elegans elegantissimus De Santis (1964) . It may further be noted that the species described by Prinsloo (1985) from the Central Namib desert, C. kuisebi Prinsloo , and the Indian species, C. latifrons Hayat et al. (1975) , appear to be very similar to the Saudi Arabian specimens.

Figures

FIGURES 53 – 57. Cheiloneurus elegans (Dalman). Female: 53, antenna; 54, head, frontal view; 55, mandibles; 56, fore wing; 57, mesosoma.