Actilasioptera falcaria (Felt)

Kolesik, Peter & Gagné, Raymond J., 2020, A review of the gall midges (Diptera: Cecidomyiidae) of Indonesia: taxonomy, biology and adult key to genera, Zootaxa 4847 (1), pp. 1-82 : 8

Actilasioptera falcaria (Felt)

[ Figs 2 a–j]

Stefaniella falcaria Felt, 1921b: 141 (in part); Gagné (in Gagné & Law 1999): 26, new combination.

Actilasioptera tumidifolium Gagné (in Gagné & Law 1999) : 25. New junior synonym.

Material examined of types of names under this taxon. Actilasioptera falcaria (Felt) : lectotype, female, designated by Gagné & Law (1999), and three female and one male paralectotypes, from “ Avicennia officinalis L” [corrected to Avicennia marina (Forssk.) Vierh. var. intermedia (Griff.) Bakh. ], Semarang, Java, Indonesia, 27-iv-1914, W. Docters van Leeuwen, Felt #a3089. The lectotype female, cleared and remounted by RJG in 1970, has the thorax and abdomen mounted laterally, the head frontally, and all body parts well-preserved except for missing wings. One female paralectotype, cleared and remounted by RJG in 1970, has the head mounted frontally, thorax and abdomen with ovipositor mounted laterally and all body parts-well preserved except for missing antennae and wings. The two remaining female paralectotypes are mounted laterally, whole and uncleared, both with the ovipositor retracted inside the abdomen and not visible, one missing both wings, the other with one damaged wing. The male lectotype is mounted laterally, whole and uncleared, with all antennal segments present but shrunken and both wings folded. Actilasioptera tumidifolium Gagné (in Gagné & Law 1999) : holotype, male, from leaf gall on Avicennia marina, Sandgate , Queensland, Australia, 23-VIII-1996, L. Law, deposited in Australian National Collection, Canberra ( ANIC).

Description. The male, female, pupa and larva were described and illustrated in Gagné & Law (1999) as A. tumidifolium . Illustrated here in Fig. 2 e–j are male and female structures of Felt’s series of A. falcaria to validate our synonymy of the two names. See elsewhere in Gagné & Law (1999) for descriptions and key to all six known species of Actilasioptera and their galls.

Remarks. In the light of the correction by DvL (1921) of the host’s name from Avicennia officinalis to Av. marina and the lack of apparent differences between adults of the two species, we consider A. falcaria and A. tumidifolium to be synonymous. Felt (1921b) did not describe the immature stages, and differences could possibly still be found to separate these two species, but there is no reason to consider them as distinct at this time. Part of Felt’s (1921b) original type series is a single paralectotype female that does not correspond to A. falcaria that causes the large leaf gall and is treated below as Actilasioptera sp.

Biology. This species causes large irregular leaf galls on Avicennia marina (Acanthaceae) . According to DvLR & DvL (1910a) the gall (No. 96, Figs 51a, b [ Fig. 2a ]) is a 1 cm large, irregular swelling situated on or very close to the leaf midrib, equally developed on both sides of the leaf, the upper side yellowish green and shiny, the underside grey and matte. The affected leaf blade is undeveloped, with ruffled edges. The gall contains several chambers, each with a single white larva. The host plant name was originally given as “ Avicennia officinalis L.” (DvLR & DvL 1910a; Felt 1921b), but DvL (1921) corrected it to Avicennia marina (Forssk.) Vierh. var. intermedia (Griff.) Bakh. , reiterated the basic gall morphology, and provided a detailed illustration of the gall in his Fig. 2 [ Fig. 2b ]. Additional illustrations and description of the gall were given by DvLR & DvL (1926, gall No. 1283 Fig. 921 [ Fig. 2c ]), with the host plant name in agreement with the 1921 correction, A. marina var intermedia .

Geographical distribution. This species is known from Indonesia (DvLR & DvL 1926; Felt 1921b) and Australia ( Gagné & Law 1999) from the following localities: Semarang, Java, ix.1909, 29-iv-1914; Jrakah, near Semarang, Java, iii.1912, iii.1913; Untung Jawa island, near Jakarta, Java, iv.1919; Sebesi island, iv.1921; Sandgate, Queensland, 23-viii-1996; Donnybrook, Queensland, 16-iv-1994; Toorbul, Queensland, 20-iii-1994; Brighton, Queensland, 4-ix-1995; and Saunders Beach, Townsville, Queensland, 8-vii-1995. Avicennia marina occurs also along the coast and on islands of east Africa, south-west, south and south-east Asia, Australia, New Guinea, Solomon Islands, New Caledonia and north of New Zealand ( Duke 1991), so Actilasioptera falcaria may have a wider distribution than currently known.

Figures

FIGURES 2a–j. Actilasioptera falcaria: a–d, galls on Avicennia marina: a, leaf upper side on top, gall cross section on bottom (Figs 51a, b of DvLR & DvL 1910); b (Fig. 2 of DvL 1921); c (Fig 921 of DvLR & DvL (1926)); d, leaf underside (Fig. 2 of Gagné & Law 1999); e–f, male: e, tarsal claw with empodium and pulvillus; f, terminalia (somewhat misshapen in the preparation), from left to right: cerci (ce), mesobasal lobe (ml), aedeagus (ae), hypoproct (hy), gonocoxite (gc), gonostylus (gs); g–k, female: g, end of abdomen (lateral); h, palpi; i, sixth flagellomere (ventral); j, same (dorsal). Figs 2k-n. Actilasioptera sp.: k, palpi; l, wing; m, galls on Avicennia marina, drawn to same scale as Fig. 2a, leaf underside on left, upper side on right (Fig. 3 of DvL (1921); n, gall cross section (Fig. 51c of DvLR & DvL 1910).