Aposthonia ceylonica (Enderlein, 1912)

(Figs. 2D–F & 3B)

Oligotoma ceylonica Enderlein, 1912: 83, fig. 56.

Oligotoma ceylonica ceylonica Enderlein. Davis, 1940: 378, figs. 51–56; Kapur & Kripalani, 1957: 126; Bradoo, 1967: 447, figs. 1–11.

Oligotoma ceylonica var. variegata Mukerji, 1935: 4, fig. 2 a–k; Menon & George, 1936: 91, pl. ii, Figs. 1 a–b, 2a–b.

Aposthonia ceylonica (Enderlein) . Ross, 2000b: 30.

Diagnosis. The male of A. ceylonica is distinguished from its relatives by the basal segment of the left cercus being less excavate in the basal three quarters and by the absence of an outcurved spine on the left cercus-basipodite. The female is brownish with light brown head, brown prothorax and forelegs, and dark brown middle and hind legs, except that the femoral-tibial joints are pale.

Holotype. Male. Stettiner Zoologisches Museum (SZM), Germany.

Type locality. Sri Lanka (Ceylon)

Material examined. The studied material consisted of 25 males and 26 females, all collected by P. Poolprasert from the following eight sites (collection accession numbers in parentheses): Site 1, 3 males and 1 female (CUMZ- EMB-Oli.2010.94-97); Site 9, 2 males and 1 female (CUMZ-EMB-Oli.2010.52-54); Site 15, 8 males and 7 females (CUMZ-EMB-Oli.2010.55-69); Site 17, 1 male (CUMZ-EMB-Oli.2010.93); Site 19, 4 males (CUMZ-EMB- Oli.2010.47-50); Site 20, 1 male (CUMZ-EMB-Oli.2010.51); Site 22, 1 male and 2 females (CUMZ-EMB- Oli.2010.70-72); Site 23, 2 males and 2 females (CUMZ-EMB-Oli.2010.73-76); Site 24, 3 males and 13 females (CUMZ-EMB-Oli.2010.77-92).

Distribution. India, Laos, Madagascar, Malaya, Mauritius, Sri Lanka and Thailand.

Description. Alate male (n = 25, mean (range) ± SD): head width × length 1.1 (0.9–1.4) ± 0.15 × 1.3 (1.0–1.5) ± 0.10 mm; body length 6.6 (5.7–7.5) ± 0.51 mm, width 1.2 (1.1–1.4) ± 0.07 mm, forewing 5.6 (4.8–6.1) ± 0.42 mm, hindwing 4.5 (3.7–5.4) ± 0.52 mm. Head capsule pale brown, longer than broad, sides convergent behind eyes. Eyes dark, moderately large. Labrum light brown, mandibles brownish, slender. Submentum trapezoidal with medial concave anterior margin (Fig. 2D), brownish. Antennae dark chocolate-brown, 17-segmented. Thorax medium brown throughout, pleurites darker. Wings grayish brown, anterior medial vein (MA) not forked. All legs medium brown throughout except for pale joints. Hind leg with only one basitarsal papilla. Abdomen similar in color to thorax. Terminalia with left hemitergite of segment 10 (10L) same width as right hemitergite (10R). Process of 10L (10LP) slender, evenly narrowed to simple round tip, process of 10R (10 RP) greatly elongated, membranous inner margin with a hooked apex. Hypandrium (H) produced back anteriorly to an obtuse process (HP), reaching as far as 10LP. Left paraproct (LPPT) weakly developed but distinct. Basal segment of left cercus (LC1) strongly excavate in the basal three-quarters.

Apterous female (n = 26, mean (range) ± SD): head width × length 1.2 (1.0–1.4) ± 0.13 × 1.3 (1.2–1.6) ± 0.10 mm; body length 6.7 (5.8–7.5) ± 0.51 mm, width 1.3 (1.2–1.5) ± 0.09 mm. Head capsule light brown, weakly convex, longer than broad. Eyes dark, smaller than in male. Antennae 15-segmented with basal 3 segments medium brown, other segments dark brown. Prothorax mostly brown except the anterior becoming light brown. Meso- and metathoracic sclerites dark brown. Forelegs concolorous with pronotum, middle and hind legs entirely dark brown except for pale femoral-tibial joints. Hind leg with only one basitarsal papilla. Abdomen brownish with tergum of segments 3–6 more reddish brown, tenth sternum symmetrically divided longitudinally into two lateral plates. Cerci entirely medium brown.

Remarks. Examples of this species have been reported by various authors under the name Oligotoma ceylonica (Bradoo 1967; Davis 1940; Enderlein 1912; Kapur & Kripalani 1957; Menon & George 1936; Mukerji 1935). Ross (2000b) transferred this species from Oligotoma to Aposthonia without description, so we have added to the details of the male characters as well as providing female characters. We found the habitats of A. ceylonic a to be on the bark of trees in orchards, public parks, plantations, beach forests, dry evergreen forests and mixed deciduous forests in every subregion of Thailand.