Melanagromyza achilleacaulis, Guglya, 2021

Guglya, Yuliia, 2021, Rearing mining flies (Diptera: Agromyzidae) from host plants as an instrument for associating females with males, with the description of seven new species, Zootaxa 5014 (1), pp. 1-158 : 12-13

Melanagromyza achilleacaulis spec. nov.

( Figs. 19–22 , 305–314 )

Holotype ( KUMN). “ Ukraine, Kharkiv Region / Nova Vodolaha District, / near Tymchenky, flood / land, River Mzha Bank / Yu. Guglya leg.”, “ 26.iii.2017 —stems of / Achillea millefolium / collected, summer 2017 /—imago reared” (1♂).

Paratypes ( KUMN). “ Ukraine, Kharkiv Region / Nova Vodolaha District, / near Tymchenky, flood / land, Riv- er Mzha Bank / Yu. Guglya leg.”, “ 26.iii.2017 —stems of / Achillea millefolium / collected, summer 2017 /—imago reared” (1♂) ; “ Ukraine, Kharkiv Region / near Tymchenky , / 49°44’N, 36°08’E / 9.iii.2019 —collected, / Yu. Guglya leg.”, “ex Achillea / millefolium , / 27.iii.2019 —imago”, (1♂) ; “ Ukraine, Kharkiv Region, / near Tymchenky , ex / Achillea millefolium , / 9.iii.2019 —collected / Yu. Guglya ”, (1♀) ; “ Ukraine, Kharkiv Region / near Tymchenky , / 49°44’N, 36°08’E / 9.iii.2019 —collected, / Yu. Guglya leg.”, “ex Achillea / millefolium , / 27.iii.2019 —imago” (3♀) .

Etymology. The name of the new species reflects the fact that the larva develops inside the stem of Achillea (“achillea”— Achillea , “caulis”—stem).

Host. Asteraceae : Achillea millefolium L.

Mine. ( Fig. 19 ) The larva forms an external stem mine not visible from outside. The larva pupates within the mine constructing a “pupal blister”.

Puparium. ( Figs. 20–22 ) Straw-coloured, matt, 2.0 mm long, with scarcely visible segmentation; surface quite smooth, except for spine bands. Posterior spiracles set on short protuberances joined towards their bases; brown, each with three large sessile bulbs arranged in one row and brought together. Anal plate is brown, not protruding above the surface of the puparium viewed from the side and directed ventro-posteriorly.

Cephalopharyngeal skeleton. ( Fig. 305 ) Both mouthhooks equal in size, with ventral portion sharply abduct- ed. Each mouthhook bears two accessory teeth. Dental sclerite large, long and waved twice. Intermediate sclerite long, narrow and straight, 1.63× as long as height of the mouthhook. The dorsal cornu bears a large “open” window and narrow arms. Ventral cornu with narrow well sclerotized portion ventrally and wide weakly sclerotized portion dorsally. Indentation index 54.

Distribution. Ukraine (Kharkiv Region).

Adult description. ( Figs. 306, 307 ) Head brownish-black. Orbit slightly projecting above eye in profile; 3 orb s, 2 fr s; frorb sta in two or three rows, thick, erect between fr s and proclinate ventrally; orbit wide, shining (frontal view); eyes are not haired in male and female; lunule moderately shining, with distinct furrow, is broad but higher than semicircle, reaching the level of the posterior fr s; oc tr large, matt, nearly reaching lunule margin; gena medially 0.17× as high as maximum height of eye; gena deepest in medial part; pped slightly elongated, rounded apically, covered with blackish hairs viewed from the side.

Wing: ( Fig. 308 ) Slightly greyish, with uniformly dark grey veins; costa reaching M 1; last section of CuA 1 0.75× as long as penultimate; calypter, margin and fringe light brown. Wing length: 2.0 mm in male, 2.1 mm in female.

Mesonotum: Black with bluish undertone, shining viewed from above; sctl and abdomen blackish with distinct yellowish-green shine; 0+2 dc s, posterior longer than anterior; acr s in 6 rows at level of anterior dc s; halter dark brown; legs black, shining as mesonotum.

Male genitalia: ( Figs. 309–313 ) Distiphallus diamond-shaped with two small curved dorsal processes, which are distinctly raised under the surface dorsally viewed from the side and laterally viewed from below. Mesophallus strongly widening distally and slightly widening proximally viewed from the side and below, with small apical invagination viewed from below. Basiphallus 0.46× as long as distiphallus, U-shaped, more sclerotized anteriorly viewed from below. Ejaculatory apodeme with blade subovate and relatively slender base. Epandrium typical for the genus, stout; surstylus bears more than 20 posteroventral sharp spines on inner surface. Hypandrium bears blunt hypandrial apodeme. Phallus 0.4 mm long, 0.53× as long as hypandrium viewed from below.

Female genitalia: ( Fig. 314 ) Egg guide and proctiger are of equal length. Blade of egg guide blunt apically, outer marginal denticles minute, scarcely visible, directed distally; medial membrane without any scales. Proctiger narrow, 4.7× as long as maximum width. Spermathecae brown, oval, unequal in size, one narrower than the other; internal duct invagination 0.7× as deep as height of spermatheca; the width of the smallest 0.75× that of the biggest one. Distinct basal collar present. Spermathecal duct weakly sclerotized.

Comments. The new species is close to Melanagromyza tripolii Spencer with the following differences: M. tripolii is a larger species with wing length 2.8 mm in male, 3.0 mm in female; eyes are haired in both sexes; calypter and fringe silvery-white, margin yellowish-brown; mesonotum and abdomen shining, greenish. Ejaculatory apodeme of the new species is longer, not diamond-shaped (as in M. tripolii ) with parallel margins; surstylus only with group of numerous spines in inner surface, without elongated setae as in M. tripolii . In addition the larva of M. tripolii feeds as an internal stem borer on Tripolium pannonicum (Jacq.) Dobrocz. and the posterior spiracles of the puparium each have one small central horn surrounded by 14–18 bulbs ( Spencer 1966).

The new species can be integrated in the key to Melanagromyza species known to occur in Ukraine on p. 413 of Guglya (2016) as follows:

7a. 3 + 3 or 2 + 2 fronto-orbital setae........................................................................ 8 - 3 + 2 fronto-orbital setae........................................................... achilleacaulis spec. nov.

Figures

FIGURES 19–28. Figures 19–22: Melanagromyza achilleacaulis spec. nov.; 19: puparium (indicated by arrow) in Achillea millefolium stem; 20–21: posterior segments of puparium; 20: lateral view; 21: posterior view; 22: posterior spiracles (posterior view). Figures 23–25: M. aenea (Meigen); 23–24: posterior segments of puparium; 23: lateral view; 24: posterior view. 25: posterior spiracles (posterior view). Figures 26–28: M. angeliciphaga Spencer; 26–27: posterior segments of puparium; 26: lateral view; 27: posterior view. 28: posterior spiracles (posterior view).

FIGURES 305–311. Melanagromyza achilleacaulis spec. nov.; 305: cephalopharyngeal skeleton; 306: frontal view of head; 307: head viewed from the side; 308: wing; 309: phallus viewed from below; 310: phallus viewed from the side; 311: ejaculatory apodeme.

FIGURES 312–314. Melanagromyza achilleacaulis spec. nov.; 312: hypandrium and phallus proportionally; 313: epandrium; 314 a–d: female genitalia proportionally; a: egg guide; b: spermathecae; c: proctiger; d: ventral receptacle.