Melanagromyza albocilia

Family

Subfamily

Genus

Species

Melanagromyza albocilia Hendel, 1931

Mine

N/A. An internal stem-borer. Feeding within the stem, pupariation internal.

Host Plants

• Convolvulus

Confusion Species

N/A.

Recording Grade

5

National Status

pRDB 1.

Puparium

Orangey-yellow, posterior spiracles pale, separated by slightly less than their own diameter, each possessing a very short central horn, surrounded by 9-12 bulbs. Length from 2.5mm in male to 2.8mm in female.

Adult

Head: Frons 1.3-1.5x as wide as eye, orbits slightly projecting above eye in profile, with 2 strong ors, 2 ori. Orbital setulae in single row, all reclinate. Eye in male with conspicuous pubescence. Gena slightly deeper in centre below eye, 0.25x as high as eye. Cheek forming a distinct ring below eye. Orbits wide; lunule slightly higher than semi-circular, sometimes with a slight central furrow. Ocellar triangle not reaching lower ors. Third antennal segment small, rounded with very short pubescence, not longer than the basal section of the arista.
Mesonotum: 2 strong dc; acr in 10 rows, reducing to 4 at level of first dc. No setulae detected on or at the side of the scutellum.
Wing: Hyaline, ultimate section of vein M₄ 0.65 (average) that of the penultimate. Costal sections (2-4) with an average ratio of 100:27:23. Length 2.1-2.2 mm in male, 2.5 mm in female.
Colour: Frons matt black. Orbits shining adjoining eye, slightly shining adjoining frons, ocellar triangle weakly shining, glossy. Lunule slightly paler than frons. Gena brownish-black, palpi black. Mesonotum shining, black with indistinct greenish tinge, abdomen greener. Calypter whitish-grey; margin very pale brown, fringe whitish. Legs dark, brownish-black with 2 strong posterolateral setae on mid tibia.
Male genitalia: Surstylus possessing a few long, thin setae and several spines on inner surface; basiphallus ring-like; basal bladder of mesophallus relatively straight; distiphallus with small, weak areas of spiculae when viewed from above; distal tubule relatively strong.
Female genitalia: Egg guide acute apically, 3.8x as long as maximum width, medial membrane with several sensilla centrally.

Additional information

Taken from Warrington 2024:

Three non-British specimens determined by Spencer were examined, reared from Convolvulus arvensis.  The two specimens from Pakistan are paratypes of Melanagromyza convolvuli, but  these do not agree with any of the original or subsequent descriptions given by Spencer (1966, 1973, 1976).  They also disagree with descriptions of Melanagromyza albocilia by Papp and Černý (2015), and the original description of Hendel (1931); their mesonotum is strikingly metallic green, the ocellar triangle is large, almost reaching lunule, and the gena is very narrow.  Another species was thought to develop within the stems of Convolvulus arvensis, M. convolvuli Spencer, 1971, but this species (which ‘agrees almost completely with albocilia but the male genitalia clearly indicate that this is a distinct species’ (Spencer 1973: 356)) was subsequently synonymised with albocilia in Spencer and Martinez (1987: 258).  As the male paratype of ‘albocilia’ is not dissected, it is not possible to confirm its identity and it is only prudent to draw attention to the notable differences between the type-material examined above and descriptions in the literature.

Within Great Britain, Spencer (1976) only cites ‘England’, with no localities provided and this species is not included in his ‘Handbooks for the Identification of British Insects’ (1972).  Within the NHMUK collection, there is a single British specimen of M. albocilia: 1.vi.52, Butley, The Thicks, Suffolk, E.A. Fonseca, det. K.A. Spencer.  The only other known British record relates to a single male collected by David Gibbs in North Somerset, 17.vii.2005.  Godfray (2020) added the braconid Chorebus cyparissa (Nixon, 1944) to the British list on the basis of a male caught in a Malaise trap set in heath with birch and pine at Santon Downham, West Norfolk (V.C. 28) between 25.vii and 5.viii.1983; the only known host of C. cyparissa is Melanagromyza albocilia (Tóth et al. 2002).  The host genus of M. albocilia is abundant throughout Great Britain (less so in Scotland) but this species and its parasitoid appear to be rare in the British Isles.