Asphondylia gochnatiae Maia

Maia, Valéria Cid, Silveira, Fernando A. O., Oliveira, Lázaro A. & Xavier, Márcia F., 2008, Asphondylia gochnatiae, a new species of gall midge (Diptera, Cecidomyiidae) associated with Gochnatia polymorpha (Less.) Cabrera (Asteraceae), Zootaxa 1740, pp. 53-58 : 54-57

Asphondylia gochnatiae Maia , sp. nov.

( Figs. 1–15 )

Adult. Body length: 3.5–4.2 mm in male (n=4); in female (from vertex to bilobed structure at posterior end of tergite 8): 3.6–4.1 mm (n=2). Head ( Fig. 1 ): eye facets hexagonal, closely appressed. Antenna: scape cylindrical, elongate, 0.13–0.15 mm long (n=2), 1.8–2.1 as long as wide; pedicel short, globose, 0.06–0.07 mm long (n=5); male flagellomeres 1–12 and female flagellomeres 1–11 cylindrical; female flagellomere 12 globose; flagellomere neck short and bare. Flagellomeres 1 and 2 not connate, flagellomere 1: 0.22–0.26 mm long in male (n=3); 0.26–0.33 mm long in female (n=2); flagellomere 2: 0.22–0.25 mm in male (n=3); 0.22–0.26 mm long in female (n=2); male flagellomeres 9 to 12 subequal in length ( Fig. 2 ); flagellomere 9: 0.18 mm long; flagellomere 10: 0.18 mm long; flagellomere 11: 0.16–0.17 mm long; flagellomere 12: 0.13–0.15 mm long); female last flagellomeres progressively and conspicuously shortened ( Fig. 3 ): flagellomere 9: 0.16 mm long; flagellomere 10: 0.12–0.13 long; flagellomere 11: 0.07–0.08 mm long; flagellomere 12: 0.05– 0.04 mm long. Circumfila anastomosing in male ( Fig.4 ) and as two interconnected rings in female ( Fig. 5 ). Frontoclypeus with about 34 setae (n=1). Labrum long-attenuate with three pairs of ventral setae. Hypopharynx of the same shape of labrum, with long anteriorly directed lateral setulae. Labella elongate-convex, each with some lateral setae and two pairs of short mesal setae. Palpus with three setose segments: segment one globose, 0.02–0.03 mm long (n=5); segment 2 cylindrical, 0.05–0.07 mm long and 1.7–3.5 times as long as wide; segment 3 elongate, tapering towards apex, 0.08–0.14 mm long and 4.0–6.5 times as long as wide.

Thorax. Anepimeron setose, other pleural sclerites asetose. Wing length (from arculus to apex): 2.5–2.7 mm in male (n=3), 2.8–3.5 mm in female (n=2). First tarsomere of each leg with an apical projection 0.03– 0.05 mm long ( Fig. 6 ). Tarsal claws simple, robust, curved beyond midlength, similar on all legs of male and female; empodia as long as bend in claws ( Fig.7 ).

Abdomen. Male ( Fig.8 ): tergites 1–7 rectangular, with complete row of posterior setae, several lateral setae, some setae at midlength, two basal trichoid sensilla and elsewhere with scattered scales. Tergite 8 constricted mesally with only two basal trichoid sensilla as vestiture. Length and mesal width of last tergites: tergite 6: 0.24 x 0.77–0.83mm; tergite 7: 0.23–0.31 x 0.61–0.72 mm; tergite 8: 0.05 x 0.33 mm. Sternites 2–7, with setae more abundant at midlength, complete row of posterior setae, several lateral setae, two basal trichoid sensilla and elsewhere with scattered scales. Sternite 8 ovoid with several scattered setae and two basal trichoid sensilla. Length and mesal width of last sternites: sternite 6: 0.25–0.34 x 0.56 mm; sternite 7: 0.31– 0.33 x 0.45–0.46 mm; sternite 8: 0.14–0.15 x 0.23–0.26 mm. Male terminalia (Fig.09): gonocoxites wide and setose, 0.16–0.18 mm long (n=3) and 1.4–1.6 times as long as wide; gonostylus short ovoid, setose, 0.06 mm long (n=3) and 0.8–1.0 as long as wide; cercus reniform, completely separate and setose; hypoproct bilobed and setose; parameres absent; aedeagus triangular, tapering gradually towards apex and pointed apically. Female ( Fig.10 ): tergites 1–7 as in male; tergite 8 with a bilobed structure at posterior end; length and mesal width of tergites 6 and 7, respectively: 0.31 x 1, 23 mm and 0.31 x 0.96 mm. Sternites 2–6 as in male. Sternite 7 ovoid, with scattered setae and two basal trichoid sensilla. Sternite 8 not sclerotized. Length and mesal width of last sternites: sternite 6: 0.33 x 0.83 mm; sternite 7: 0.64 x 0.70 mm. Ovipositor: needle part 1.4–1.6 mm long and 2.59–2.66 times as long as sternite 7.

Pupa. Color: brownish. Length: 3.95–4.55 mm (n=3). Head ( Fig.11 ): antennal horn 0.30–0.38 mm long (n=4), apicomesal margin serrated; cephalic setae 0.04–0.06 mm long (Fig.) (n=4); upper frontal horn simple, 0.14–0.15 mm long (n=4); lower frontal horn trilobed, 0.05–0.06 mm long (n=2); two pairs of lower facial papillae: one pair setose, seta 0.015–0.025 mm long (n=4), the other asetose; three pairs of lateral facial papillae: one pair setose, seta 0.01–0.015 mm long (n=2), the others without setae. Upper cephalic margin thickened laterally. Thorax: prothoracic spiracle setiform, elongate, curved, 0.09–0.12 mm long (n=5) ( Fig. 12 ). Abdomen ( Fig. 13 ): segments 2–9 with transverse rows of dorsal spines.

Larva. Body elongate and cylindrical. Length: 2.7 mm (n=1). Integument rough. Spatula ( Fig. 14 ) with four well developed teeth, the outer pair longer than the inner; surrounding area pigmented; sternal papillae setose (setae 0.02 mm long), four setose lateral papillae on each side of spatula. Terminal segment short, convex, with four pairs of terminal papillae, one pair corniform, the others with setae.

Galls. Induced mainly on the leaves ( Fig. 15a ), galls also occur rarely in pedicels ( Fig. 15b ). Galls may be isolated but are more frequently coalescent (up to 31 galls/leaf). A single larva is found in the one-chambered, spheroid gall. Externally the galls are yellow, spheroid and covered with long, whitish to yellowish trichomes. Gall abundance was higher during leaf flushing (15.83 gall/plant, 1.47 gall/leaves in October) but decreased during the dry season (1.03 gall/plant, 0.06 gall/leaves in April), when G. polymorpha leaves were senescent. Average gall diameter was 3.66 (± 0.94mm; n = 4637), ranging from 5.39mm in September to 2.29mm in April. Only 29.6% of the larvae survived, but a strong temporal effect was also observed in larvae survival. In September larvae survival was 48.79% but in April it was only 12.9%. Most larvae died as a result of unknown factors. Predation by caterpillars, parasitism by microhymenopterans and pathogenic fungi accounted for a small proportion of dead larvae.

Type material. Holotype male. BRAZIL. Minas Gerais: Luz, X.2005, F. A. O. Silveira col.. Paratypes: same data as holotype, 3 males, 2 females, 11 pupal exuviae, and 1 larva.

Etymology. The specific name is the genitive of the host plant generic name.

Remarks. Asphondylia gochnatia sp. n. differs from all other Neotropical species on Asteraceae in having the following characters: tarsal claws similar on all legs of both sexes; pupal upper frontal horn with single apex; pupal lower frontal horn with three teeth similar in length; prothoracic spiracle relatively short; larval spatula with four teeth, the two midlle sligthly shorter than the lateral teeth; spatula stalk moderately developed; and four pairs of terminal papillae, one pair corniform, the others with tiny setae.

Figures

FIGURES 1 – 8. Asphondylia gochnatiae Maia, sp. nov. 1, male head (frontal). 2, male, flagellomeres 10 – 12. 3, female, flagellomere 10 – 12. 4, male, flagellomere 5. 5, female, flagellomere 5. 6, female, foreleg, tarsomere 1. 7, male, midleg, tarsal claw and empodium. 8, male, abdominal segments 5 – 8 (lateral).

FIGURES 9 – 14. Asphondylia gochnatiae Maia, sp. nov. 9, male terminalia (dorsal). 10, female, abdominal segments 4 – 8 (lateral). 11, pupal head (frontal). 12, pupa, prothoracic spiracle. 13, pupa, abdominal segments 8 – 9. 14, larva, prothoracic spatula, sternal and lateral papillae (ventral).

FIGURE 15 a – b. Gall of Asphondylia gochnatiae Maia, sp. nov. 15 a, on leaves. 15 b, on pedicels.