Alloxysta abdera Fergusson, 1986

Fig. 1

Alloxysta abdera Fergusson, 1986: 10 .

Type material

Holotype

♂, with the following labels: “ England: Lancs. woodland, Belmont, 25.ix.1981 ”, “ Holotype ” (round label with red margins), “ ♂ ”, “ Holotype of Alloxysta abdera det. N.D.M. Fergusson, 1984”, “ B.M. Type Hym. 7.175”.

Paratype

♀, with the following labels: “ England: Lancs., woodland, Belmont, 25.ix.1981 ”, “ Alloxystinae ” (handwritten), “ Paratype ” (round label with yellow margins), “ A. abdera det. N.D.M. Fergusson”.

Redescription

COLORATION. Head yellowish brown, mesosoma and metasoma very dark brown. Antennae dark yellow. Legs yellow and veins yellowish brown.

HEAD. Transversely ovate, smooth and shiny, wider than high in front view; with setae below, between and a few above toruli. With few setae on vertex and with many setae on face. Transfacial line 1.0 x height of compound eye. Malar space 0.6 x height of compound eye.

ANTENNA. Female: 13-segmented, filiform. All antennomeres covered with sparse setae. F1-F3 thinner and smoother than remaining flagellomeres; F4-F11 club-shaped, with rhinaria. Pedicel 1.9 x as long as wide; F1 4.1 x as long as wide; F2 3.8 x as long as wide; F3 3.3 x as long as wide; F4 2.5 x as long as wide. F1 1.4 x as long as pedicel; F1 subequal to F2; F2 1.2 x as long as F3; F3 1.1 x as long as F4; F4-F11 subequal in length, width and shape (Fig. 1C). Male: 14-segmented, filiform. All antennomeres covered with sparse setae. F1 thinner and smoother than remaining flagellomeres; F2-F12 club-shaped, with rhinaria. Pedicel 2.0 x as long as wide; F1 3.2 x as long as wide; F2 2.1 x as long as wide; F3 2.6 x as long as wide; F4 2.4 x as long as wide. F2 curved. F1 1.2 x as long as pedicel; F1 1.1 x as long as F2; F3 1.1 x as long as F2; F3-F12 subequal in length, width and shape (Fig. 1D).

MESOSOMA. Pronotum covered with abundant setae, less setae on anterior margin, with two thick carinae clearly visible under the pubescence (Fig. 1B). Mesoscutum smooth and shiny, round in dorsal view with scattered setae. Scutellum also smooth and shiny with few scattered setae, being abundant on apex. Height of mesopleural triangle along anterior margin 1.6 x the height of mesopleuron. Propodeum entirely covered by setae, with two carinae forming a thick plate, with setae on top and sides slightly curved (Fig. 1E).

FORE WING. Longer than body, 1.4 x as long as mesosoma and metasoma together in both male and female (Fig. 1A). Covered with dense pubescence; marginal setae present. Completely open radial cell, 2.2 x as long as wide in both male and female. R1 short and curved; Rs long and curved. R1 and Rs not reaching costal margin (Fig. 1F).

METASOMA. Anterior part with an incomplete ring of setae, glabrous at centre, wider laterally. Metasoma smooth and shiny, T3 and T4 clearly distinguished.

Remarks

According to the original description, Alloxysta abdera is represented by 9 specimens (6 ♂♂ and 3 ♀♀) in BMNH. One male was designated as holotype by Fergusson and the rest of the specimens as paratypes; we have examined only the holotype (♂) and one paratype (♀). This species is very similar to A. pallidicornis (Curtis, 1838) because both species have a completely open radial cell, pronotal and propodeal carinae present, and flagellomeres club-shaped and with rhinaria from F2, but they differ in the ratios between F2 and F3. F3 is slightly longer than F 2 in A. abdera (Fig. 1C), whereas in A. pallidicornis F2 is longer than F3; size of radial cell: 2.2 x as long as wide in A. abdera (Fig. 1F) but 2.6 x as long as wide in A. pallidicornis; shape of propodeal carinae: with two carinae forming a thick plate, with setae on top and sides slightly curved in A. abdera (Fig. 1E) but with two carinae well defined and separated by setae in the first half and forming a plate in the last half in A. pallidicornis .