Phytomyza torilisi, 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 : 87-90

Phytomyza torilisi spec. nov.

( Figs. 257–260 , 662–672 )

Holotype ( KUMN). “ Ukraine, Kyiv Region, / near Tarasivka / 50°09’49”N, 30°35’49”E, / 22.v.2019, flood land / Yu. Guglya leg.”, “serpentine mines with / larva on Torilis / japonica , 24.v.—pupariation / outside the mine, / 6.vi.2019 —imago” (1♂).

Paratypes ( KUMN). “ Ukraine, Kyiv Region, / near Tarasivka / 50°09’49”N, 30°35’49”E, / 22.v.2019, flood land / Yu. Guglya leg.”, “serpentine mines with / larva on Torilis / japonica , 24.v.—pupariation / outside the mine, / 6.vi.2019 —imago” (3♂ 1♀) .

Etymology. The name of the new species reflects its host specialization.

Host. Apiaceae : Torilis japonica (Houtt.) DC.

Mine. ( Fig. 257 ) The larva forms a white irregular linear upper surface mine. The width of the mine gradually increases during the course of the larval life. Pupation takes place outside the mine in the soil.

Puparium. ( Figs. 258–260 ) Brown, slightly shining, 1.8 mm long, with shallow but distinct segmentation; last abdominal segment slightly lighter than overall tone of puparium. Surface quite smooth except for wide minute bands of minute spines. Posterior spiracles set flat on the body cuticle and entirely separate; black, with numerous fine sessile bulbs in an elliptical configuration. Ventral portion of last abdominal segment sharply and strongly protruding posteriorly viewed from the side. Anal plate directed ventro-posteriorly.

Cephalopharyngeal skeleton. ( Fig. 662 ) Rght mouthhook larger than the left, each with sharp abducted portion directed anteriorly and bearing two wide and sharp accessory teeth. Intermediate sclerite long, narrow and straight, 1.94× as long as maximum height of left mouthhook. The ventral half of the mouthhook and most of the intermediate sclerite are strongly sclerotized, the rest of the sclerites much less so. Indentation index 87.

Adult description. Head: ( Figs. 663, 664 ) Orbit not projecting above eye in profile; 2 orb s (upper very slen- der), 2 fr s (lower very slender), all areolae dark, frorb sta very sparse, proclinate; hind margin of eye dark brown, both vt and posterior orb s on dark area; orbit wide, without distinct contours (frontal view); frons and orbit yellow, matt; lunule and face darker, brownish; lunule of medium height, broad, flattened posteriorly, reaching the level of the posterior fr s; oc tr black, small, with distinct contours, reaching the level between upper and anterior orb s; gena medially 0.28× as high as maximum height of eye; gena dark yellow, higher posteriorly; scape, pedicel and pped brownish-black; pped small, rounded apically, with long, thick, brown pubescence viewed from the side.

Wing: ( Fig. 666 ) Slightly greyish, with dark grey costa, and other veins thin and pale; costa ending abruptly after R 4+5; second crossvein absent; calypter and margin beige as the wing base, fringe with long dark grey sparse hairs. Wing length: 2.0 mm in male, 2.2 mm in female.

Mesonotum, scutulum and abdomen: Brownish-grey, silky shining viewed from above; anepist dorso-medially, pprn posteriorly and anepm light yellow ( Fig. 665 ); posterior margins of all abdominal segments yellow; 1+3 dc s, posterior dc s 1.3× as long as others; acr s in 3 rows at level of anterior dc s; acr s absent at level of posterior dc s; halter yellow; all legs blackish brown, slightly shining, with fore knees and basal 0.6 of fore tibiae yellow.

Male genitalia: ( Figs. 669–672 ) Epandrium subovate; hypandrium equilateral triangle-shaped, with short stout arms and wide, blunt hypandrial apodeme viewed from below. Pregonite diamond-shaped, with numerous small setae along inner and anterior margin and two strong setae near the inner basal corner. Distiphallus weakly sclerotized, equal in length with basiphallus. Hypophallus consists of a pair of ventro-posteriorly directed sclerites, that are long, narrow and connected membranously. Basiphallus long, with narrow, strongly sclerotized, waved lamellae; left lamella bifurcated anteriorly. Seven to eleven large spines located dorsally between the lamellae in the anterior half. Ejaculatory apodeme rather small, wide, triangular; sperm sac 1.45× as wide as height of apodeme. Phallus 0.6 mm long.

Female genitalia: ( Figs. 667 , 668 ) Capsule of spermatheca relatively small, 0.15× as high as height of anterior part of oviscape. Spermathecae unequal in size, brown, oval, with corrugated surface, flattened basally and apically, without basal collar, wider than high. Internal duct invagination trapezoid, 0.7× as deep as height of spermatheca. Spermathecal duct weakly sclerotized. Ventral receptacle flattened S-shaped, with weakly sclerotized tail that is bowl-shaped in basal half. Body of receptacle spherical with slightly curved basal connecting tube, strongly sclerotized, equal in diameter with smaller spermatheca; with opening 0.66× as wide as diameter of spherical part of body.

Distribution. Ukraine (Kyiv Region).

Comments. Externally the new species is distinguishable from Phytomyza pastinacae Hendel by having the costa ending abruptly after R 4+5, beige margin of calypter, bright coloration of anepisternum, legs uniformly brown with only fore knees yellow, and dark and long pubescence of the pped. In the male genitalia, the ejaculatory apodeme is very small and strongly differ in shape from P. pastinacae ( Fig. 670 , in Papp & Cerny 2019: fig. 164 E). The spermatheca of the new species has a corrugated surface, and they are flattened apically and basally, whereas in P. pastinacae the surface is plain, flattened basally and narrowed apically ( Figs. 621 a , 668 a ). The cephalopharyngeal skeleton in the new species is smaller and generaly much brighter and more slender than in P. pastinacae . The puparia of these species are similar, but the number of posterior spiracular bulbs differs ( P. pastinacae 16–25, P. torilisi 13).

The new species can be integrated into the key on page 185 of Papp & Černý (2019) as follows:

49a. Wing base, calypter and margin beige, fringe long with sparse dark grey hairs; basiphallus with 7–11 large spines arranged in three irregular lines ( Fig. 669 )............................................................ P. torilisi spec. nov. - Wing base and calypter white, margin and fringe dark; quantity of spines between sclerites of mesophallus different...... 50

Figures

FIGURES 253–260. Figures 253–256: Phytomyza plantaginis Robineau-Desvoidy; 253–254: mines in Plantago major leaf; 253: on upper leaf side; 254: on lower leaf side with puparia; 255: empty puparium viewed from the side; 256: posterior segments of puparium (posterior view). Figures 257–260: P. torilisi spec. nov.; 257: mines in Torilis japonica leaf; 258–259: posterior segments of puparium; 258: lateral view; 259: posterior view. 260: posterior spiracles (posterior view).

FIGURES 662–667. Phytomyza torilisi spec. nov.; 662: cephalopharyngeal skeleton; 663: frontal view of head; 664: head viewed from the side; 665: thorax viewed from the side; 666: wing; 667: oviscape, ventral receptacle and spermathecae proportionally.

FIGURES 668–672. Phytomyza torilisi spec. nov.; 668 a–b: spermathecae and ventral receptacle proportionally; a: spermathecae; b: ventral receptacle; 669: phallus and ejaculatory apodeme proportionally viewed from the side; 670: ejaculatory apodeme; 671: hypandrium viewed from the side; 672: epandrium and hypandrium viewed from below.

FIGURES 617–621. Phytomyza pastinacae Hendel; 617: cephalopharyngeal skeleton; 618: frontal view of male head; 619: female head viewed from the side; 620: oviscape, ventral receptacle and spermathecae proportionally; 621 a–b: spermatheca and ventral receptacle proportionally; a: spermatheca; b: ventral receptacle.