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; F 1 –F 3 brownish yellow; F 4 and F 5 yellow; F 6 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 F 1 and F 2 combined; F 1 always slightly but distinctly longer than broad; F 2 shorter than F 1, and quadrate to slightly longer than broad; F 3 slightly longer than broad to slightly broader than long, longer than F 2 (one specimen) or subequal to F 2 (one specimen), or shorter than F 2 (3 specimens) (these relative lengths may vary in the two antennae of a single specimen); F 1 –F 3 each smaller than F 4; F 4 slightly shorter than F 5; F 4 and F 5 quadrate or each slightly longer than broad; F 6 usually broader than long, but in one specimen, longer than broad; clava slightly longer than F 4 –F 6 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 F 1 longer than broad, F 2 quadrate and shorter than F 1, F 3 subequal to or slightly longer than F 2, F 1 –F 3 each smaller than F 4, and F 6 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 F 1–3 are smaller than F 4, but the pedicel is shorter than F 1 and F 2 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 F 1 and F 2 combined, F 1–6 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.