Tachydromia apterygon Plant & Deeming, 2006

Gonçalves, Ana Rita, Grootaert, Patrick, Andrade, Rui, Paulo, Octávio S. & Mengual, Ximo, 2021, Revision of the morphology, phylogenetic relationships, behaviour and diversity of the Iberian and Italian ant-like Tachydromia Meigen, 1803 (Diptera: Hybotidae), European Journal of Taxonomy 732, pp. 1-56 : 16-18

Tachydromia apterygon Plant & Deeming, 2006

Figs 3 , 16 I–J, 19 J, 22–24

Tachydromia apterygon Plant & Deeming, 2006: 13 (male only).

Diagnosis

Small (length = 2 mm), slender, overall dark, with minute bilobed squamiform wings ( Fig. 22 ) in both sexes and halteres absent. Frons, vertex and occiput largely covered by grey microtrichia; 1 pair of lateroclinate ocellars; 1 pair of proclinate verticals; palpi pale yellow, antennae with scape and pedicel yellow, postpedicel brown; proboscis shiny black; postpedicel sub-conical, similar length as of pedicel. Thorax black with portion of episternum densely covered with grey microtrichia. Legs with colour pattern of yellowish and dark brown to black; fore tibia with ciliation of short coarse setae. Mid tibia with anteroventral spur at apex, produced into short apical elongation, about as long as diameter of tibia at apex ( Fig. 19J ); spur with several distinct setae and, on distal half margin, a few short, stout, curved spinose setae. Abdomen black, covered with grey microtrichia and short setae, longer at hind margin of last sternite.

Type material examined

Holotype ITALY • 1 ♂; Lazio , 10 km south of Forca d’Acero, on road to Sora; 1 Jul. 2005; J.C. Deeming leg.; NMWC.

Additional material examined

ITALY • 5 ♂♂, 10 ♀♀; Frosinone, San Donato Val di Comino ; 41°43′58.7″ N, 13°49′12.2″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg. • 2 ♂♂; L’Aquila, Gioia dei Marsi , Parco Nazionale D’Abruzzo Lazio e Molise; 41°51′34.0″ N, 13°46′52.1″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg. • 19 ♂♂, 13 ♀♀; L’Aquila, Pacentro ; 42°02′56.7″ N, 14°02′51.7″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg. • 18 ♂♂, 14 ♀♀; Pescara , Sant’Eufemia a Maiella; 42°06′01.2″ N, 14°02′10.5″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg. • 13 ♂♂, 13 ♀♀; L’Aquila, Ofena ; 42°23′06.1″ N, 13°45′37.8″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg. • 2 ♂♂; Pescara, Farindola ; 42°23′45.7″ N, 13°47′06.8″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg. • 2 ♂♂, 3 ♀♀; Lazio, Leonessa ; 42°30′59.3″ N, 12°59′10.9″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg.; ZFMK • 4 ♂♂, 3 ♀♀ (all male terminalia studied, RBINS); Lazio, Posta ; 42°31′51.2″ N, 13°03′37.4″ E; 26–29 Jun. 2017; A.R. Gonçalves and R. Andrade leg.

Description

Female (previously undescribed)

Similar to male. Micropterous, wing round, brownish, bilobate, apical margin of posterior lobe bearing 1 long seta, anterior lobe bearing 3 shorter setae, lobes covered with grey microtrichia. Differs from male in following: legs mainly covered with microtrichia and regular rows of setae; spur on mid tibia absent; cercus pale brown with grey microtrichia and long setae; a few longer setae on apical sternites.

Distribution and habitat

Italy. Currently, this species is only known from the central Apennine Mountains ( Fig. 23 ). It occurs on the edge of forests of Fagus sylvatica L. ( Fig. 24 ), on the leaf litter and short herbaceous vegetation, where it can be abundant. It has also been found in mixed deciduous woodland at lower altitudes, inside the forest, on the leaf litter.

Remarks

Despite the sampling effort at the end of July, the species was not found at the mixed deciduous woodland type locality. However, it was still very abundant at higher altitudes. The type specimen was collected at the beginning of July, so by the end of the month, it may already be too hot and dry for this species to survive at lower altitudes.

Figures

Fig. 3. Terminalia of Tachydromia apterygon Plant & Deeming, 2006 from Italy, Lazio, Posta (RBINS). A. Right surstylus and right epandrial lamella. B. Epandrium with cerci. C. Left epandrial lamella and left surstylus. D. Right surstylus. Scale bar: 0.1 mm.

Fig. 16. Habitus of live specimens of the Iberian ant-like Tachydromia Meigen, 1803 and the Italian flightless Tachydromia. Males are pictured in the left column, females in the right.A–B. T. iberica (Arias, 1919). C–D. T. semiaptera (Gil Collado, 1923). E–F. T. pieltaini (Gil Collado, 1936). G–H. T. pandellei (Séguy, 1941). I–J. T. apterygon Plant & Deeming, 2006 (Italy).

Fig. 19. Images obtained by scanning electron microscopy of the spur-like structures present on the apical portion of the male mid tibia. A. T. lusitanica (Grootaert, Shamshev & Andrade, 2009). B. T. pandellei (Séguy, 1941). C. T. pieltaini (Gil Collado, 1936). D. T. ebejeri Gonçalves, Grootaert & Andrade sp. nov. E–F. T. semiaptera (Gil Collado, 1923). G. T. stenoptera Gonçalves, Grootaert & Andrade sp. nov. H. T. cantabrica Gonçalves, Grootaert & Andrade sp. nov. I. T. nigrohirta Gonçalves, Grootaert & Andrade sp. nov. J. T. apterygon Plant & Deeming, 2006. Scale bars: 10 µm.

Fig. 22. Image obtained by scanning electron microscope (SEM) of the micropterous wing of a male of Tachydromia apterygon Plant & Deeming, 2006. Scale bar: 10 μm.

Fig. 23. Distribution of Tachydromia apterygon Plant & Deeming, 2006 in Italy. Nine localities are currently known.

Fig. 24. Forest of Fagus sylvatica L. in the Apennine Mountains, where Tachydromia apterygon Plant & Deeming, 2006 can be found.