Ablabesmyia (Ablabesmyia) maculitibialis Chaudhuri, Debnath et Nandi

Niitsuma, Hiromi & Tang, Hongqu, 2019, Taxonomic review of Ablabesmyia Johannsen (Diptera: Chironomidae: Tanypodinae) from Oriental China, with descriptions of six new species, Zootaxa 4564 (1), pp. 248-270 : 254-256

Ablabesmyia (Ablabesmyia) maculitibialis Chaudhuri, Debnath et Nandi

( Figure 4 )

Ablabesmyia (Ablabesmyia) maculitibialis Chaudhuri, Debnath et Nandi, 1983: 907 .

Material examined. 1 male, CHINA: Macau Special Administrative Region, Co-Tai, wetland near Taipa Houses Museum , 20.vii.2014 ; 1 male, Macau Special Administrative Region, Coloane Island, Hac-Sa Reservoir , 22°07.514'N, 113°34.232'E, 100 m alt., 10.xi.2014 ; 1 male, Hainan Province, Tunchang County, Nanlyu Town, Zhenghong Reservoir , 7.ii.2015 .

Description. Male (n=3). Total length 3.1–3.2, 3.2 mm.

Coloration. Thorax brown with darker scutal vittae, anepisternum II, preepisternum, scutellum and postnotum. Abdomen mainly brown; T I–V each with dark anterior transverse and lateral longitudinal bands; T VI–VIII entirely dark brown; hypopygium with dark brown gonocoxite. Wing costa ( Fig. 4A ) with 3 dark spots at apices of radial branches. Fore- and midfemora white, slightly darkened on basal 2/3, each with sub-apical dark band. All tibiae ( Fig. 4B ) white, each with 4 dark bands. Relative positions of sub-basal, basal-median and apical-median bands on foretibia: 0.90; 0.73–0.76, 0.75; 0.39–0.42, 0.41, from apex; midtibia: 0.87–0.90, 0.89; 0.71–0.73, 0.73; 0.40–0.44, 0.42; hind tibia: 0.90–0.91, 0.91; 0.72–0.73, 0.72; 0.42–0.46, 0.44.

Head. Temporals 23–26, 24. AR 1.8–2.0 (2). Clypeus with 29–40, 33 setae. Lengths of palpomeres 1–5 (µm): 50 (1), 103 (1), 135 (1), 125 (1), 278 (1).

Thorax. Lateral antepronotals 11–15, 13; acrostichals more than 50; dorsocentrals 23–31, 28; humerals 18–33, 26; prealars 17–22, 19; supraalars 1; scutellars 37–52 (2).

Wing. Length 1.9–2.2, 2.0 mm. Squama with 35–37 (2) setae. VR 0.82–0.89, 0.85.

Legs. Ti I spur 49–53, 51 µm long with 6–8 (2) lateral teeth. Ti II spurs 59–64, 62 and 28–34, 32 µm long, with 4–7 (2) and 4–6 (2) lateral teeth, respectively; inner spur/outer spur 1.7–2.3, 2.0. Ti III spurs 47–66, 59 and 32–52, 40 µm long, with 4–5 (2) and 3–4, 4 lateral teeth, respectively; inner spur/outer spur 1.3–1.7, 1.5. Ti III comb consisting of 4–5, 5 bristles. Lengths and proportions of legs as in Table 2.

Hypopygium ( Fig. 4C ). T IX with 2 setae on each side. Gonocoxite 168–187, 177 µm long, with weak basolateral bulge. Aedeagal complex ( Fig. 4D ) with dorsal lobe 30–37, 35 µm long, stout, bearing smooth apex; blade 48–52, 50 µm long, curved dorsally, tapering toward pointed apex; lateral lobe 81–94, 87 µm long, 1.7–1.8, 1.8, times as long as blade, bearing apicolateral teeth; lateral filaments not evident. Gonostylus 170–175, 172 µm long, almost as long as gonocoxite.

Pupa and larva. Unknown.

Remarks. Although the tibia is three-banded in most species of the subgenus Ablabesmyia , four-banded tibiae occur in Australian A. (A.) notabils (Skuse) , African A. (A.) rufa (Kieffer) , A. (A.) appendiculata (Kieffer) and A. (A.) dusoleili Goetghebuer, and Indian A. (A.) ornatipes (Kieffer) as well as A. (A.) maculitibialis . Further, Brazilian A. ducke Neubern , A. fazzari Neubern , A. gessnerae Neubern and A. pinhoi Neubern also possess fourbanded tibiae, wings with separate dark spots and an apically expanded sub-terminal seta on the male gonostylus. As explained previously, however, these Brazilian species were not given any subgeneric status in the original descriptions ( Oliveira et al. 2013).

For comparison, major characters of these ten species are summarized in Table 3, according to Freeman (1961) and Roback (1982a, b) for A. (A.) notabilis, Freeman (1955) for A. (A.) rufa, Freeman (1955) and Harrison (1978) for A. (A.) appendiculata and A. (A.) dusoleili , and Kieffer (1910) for A. (A.) ornatipes which is known about only the female, and Oliveira et al. (2013) for A. ducke , A. fazzari , A. gessnerae and A. pinhoi .

The male of A. (A.) maculitibialis is characterized by the forefemur darkened on the basal two thirds and subapex, the four-banded tibia, the wing with three dark spots at apices of R 1, R 3 and R 4+5, and the aedeagal complex with a bare dorsal lobe, a slender blade tapering toward a pointed apex and a very long lateral lobe with apicolateral teeth. In the original description, Chaudhuri et al. (1983: 907) miscalculated the male antennal ratio, and it is 2.0, not 1.1, based on the relative lengths of flagellomeres.

Notes: The aedeagal complex of A. (A.) rufa is not described. The male of A. (A.) ornatipes is unknown.

Figures

FIGURE 4. Ablabesmyia (Ablabesmyia) maculitibialis Chaudhuri, Debnath et Nandi, male. A, Wing; B, femora and tibiae of P 1–3, showing pigmentation pattern; C, hypopygium, dorsal view; D, aedeagal complex. l/L, Relative position of tibial apicalmedian band of P 3.