Hexacladia dichelopsis Torrens & Fidalgo, 2017

Torrens, Javier, Fidalgo, Patricio, Fernandez, Celina & Punschke, Eduardo, 2017, A new species of Hexacladia Ashmead (Hymenoptera, Encyrtidae) and new record of Hexacladia smithii Ashmead as parasitoids of Dichelops furcatus (Fabricius) (Hemiptera, Pentatomidae) in Argentina, Journal of Hymenoptera Research 61, pp. 75-83 : 76-77

Hexacladia dichelopsis Torrens & Fidalgo sp. n.

Figs 1-10

Diagnosis.

Distinguished from other species by the following combination of characters: general body color dark brown to black (Figs 1 , 2 ); small wings, fore wing 1.3 × as long as length of mesosoma (Figs 1 , 2 ); female with costal cell with four or five setae, distal third of the upper margin without marginal setae, dark areas of the wing disc well evident; male with costal cell with abundant setae (25 to 27), basal third with eight to nine setae, distal third of the upper margin with marginal setae and dark areas of the wing disc poorly defined; male with F7 2.0 × as long as F6, branch of F6 0.5 × length of F6.

Description.

Female (holotype): length, 2.3mm. General body color dark brown to black dorsally, being paler toward head, scape and pedicel, axilla, metanotum, apex of tibiae and tarsi, propodeum and base of first tergite of gaster; entire body lighter ventrally, femora and metasoma slightly darker than the rest; setae on dorsum of mesosoma translucent (Figs 2 , 6 ). Wings largely hyaline, but fore wing with two brown areas, the first and smaller behind base of parastigma, with about 40 strong dark brown setae, the distal area is most extensive, begins behind marginal vein and occupies most of wing apex, alar disc between the two brown areas with light setae (Fig. 8 ).

Head 1.3 × as broad as high. POL 2.1 × LOL; POL 1.3 × OOL. Head with fine, raised, imbricate-reticulate sculpture, well-marked and moderately deep on frons and vertex, and slightly marked and irregular on face and gena; anterior ocellus connected to toruli by a shallow groove; interantennal area narrow and smooth; frontovertex and face with inconspicuous, decumbent setae, each slightly shorter than diameter of anterior ocellus (Fig. 6 ). Eyes separated by 1.7 × their height. Malar space 0.9 × height of eye. Antenna 9-segmented, flagellar segments cylindrical. Flagellum 1.6 × as long as head height; length of F1 0.6 × length of scape, and 2.8 × as long as broad; clava 3.4 × as long as broad. Antenna (Fig. 10 ) apically with slightly curved setae in all segments, more dense on funicle; funicle with linear sensilla only on F3-F6 (Fig. 10 ).

Mesosoma with fine, raised, polygonally-reticulate to imbricate-reticulate sculpture on mesoscutum (Figs 2 , 4 ). Pronotum with small and decumbent setae, head overlapping the pronotum. Mesoscutum 1.7 × as broad as long, with small and decumbent setae (Fig. 4 ). Scutellum 1.1 × as long as maximum width; axilla and scutellum with coarse reticulate sculpture slightly deeper than that on mesoscutum, and with semi-erect and longer setae than the mesoscutum; scutellum humped, strongly and fairly evenly curved in profile (Fig. 4 ); propodeum with a group of about 11-14 setae outside spiracle. Fore wing 3.1 × as long as broad, costal cell with seven or eight setae dorsally, linea calva broad and open posteriorly, basal cell with five to eight setae, submarginal vein with 11 bristle-like setae, postmarginal vein slightly shorter than stigmal vein, marginal fringe present, stigmal vein without uncus and with three or four placoid sensilla; hind wing 3.7 × as long as broad.

Metasoma 1.5 × as long as broad. Hypopygium very nearly reaching apex of metasoma; apically with a pair of short lateral processes either side of a wide, shallow, median invagination; with about 6 hypopygial hairs (Fig. 2 ). Ovipositor not observed.

Variation. The length of the female varies between 2.2-2.6 mm. The coloration in some specimens are darker than holotype, otherwise very little variation in material examined.

Male. Similar to female except for following: The length of the male varies 1.7-1.9 mm. General body color and head darker than female (Figs 1 , 3 , 5 ), fore wing with areas paler, with costal cell with abundant setae (25 to 27), basal third with eight to nine setae, stigmal vein with four or five placoid sensilla (Fig. 7 ); antenna with funicle segments longer than broad and with a elongate dorsal branch (Fig. 9 ); F1 a little longer than F2 and F3; F4 longer than F5 and F6; F7 is the longest flagellomere; branch of F1 2.0 × as long as F1 and as long as F1 and F2 together; branch of F6 0.5 × length of F6. Length:width of the antennal segments in the following relationship: scape (48:7), pedicel (9:8), F1 and branch of F1 (14:5 and 29:3), F2 and branch of F2 (13:5 and 31: 2,5), F3 and branch of F3 (13:5 and 30:2), F4 and branch of F4 (19:5 and 20:2), F5 and branch of F5 (16:5 and 14:2), F6 and branch of F6 (16:6 and 9:2), F7 (35:7).

Material examined. Holotype ♀: ARGENTINA, Santa Fé, Zavalla, Campo experimental Villarino, Fac. Cs. Agrarias, 2.v.2016., E. Punschke, ex. diapausing adult of Dichelops furcatus on soybean stubble (MACN). Paratypes (11 ♀♀ and 23 ♂♂): same locality as holotype, 2.viii.2015 (MACN, 11 ♀ and 2 ♂), 2.v.2016 (IFML, 11♀♀, IFML; CRILAR-En, 10 ♀♀).

Figures

Figures 1 - 10. Hexacladia dichelopsis sp. n.: 1 habitus (male) 2 habitus (female) (magnified apex of hypopygium, lateral and ventral view) 3 mesosoma (male, dorsal) 4 mesosoma (female, dorsal) 5 head (male, frontal) 6 head (female, frontal) 7 fore wing (male, lateral) 8 fore wing (female, lateral) 9 antenna (male, lateral) 10 antenna (female, lateral).