Phytoliriomyza alpicola Strobl

Kato, Makoto, Yamamori, Luna & Imada, Yume, 2022, Diversity underfoot of agromyzids (Agromyzidae, Diptera) mining thalli of liverworts and hornworts, ZooKeys 1133, pp. 1-164 : 1

30. Phytoliriomyza alpicola Strobl

Figs 56 , 57

Agromyza alpicola Strobl, 1898: 272.

Liriomyza alpicola Hendel, 1931: 206.

Phytoliriomyza alpicola Spencer, 1971: 162.

Lemurimyza alpicola .Papp, 1984: 306.

Phytoliriomyza alpicola Sasakawa, 2008: 137; Černý et al. 2020: 213.

Material examined.

Japan: On Conocephalum salebrosum : 1♀, Yuni-ishikari-gawa, Soun-kyo, Kamikawa, Hokkaido, 5-VI-2016 (as larva), emerged on 22-VI-2016; 1♂, Samani-dam, Samani, Hokkaido, 1-VI-2021 (as larva), emerged on 3-VII-2021; 1♀, Renge-onsen, Itoigawa, Niigata Pref., 15-X-2011 (as larva), emerged on?-VI-2011; 27♂36♀, Ikawa-toge, Aoi-ku, Shizuoka Pref., 26-V-2021 (as larva), emerged on 30-V-27-VI-2021.

On Conocephalum orientalis : 5♀, Iwadate, Hachimori, Happo, Yamamoto, Akita Pref., 16-XI-2014 (as larva), emerged on 2-18-V-2014; 1♀, Futto, Toei, Kitashidara, Aichi Pref., 9-III-2013 (as larva), emerged on 2-V-2013; 1♀, Nekata, Hamakita, Hamamatsu, Shizuoka Pref., 8-III-2012 (as larva), emerged on 8-V-2012; 1♀, Saruyama, Monzen, Wajima, Ishikawa Pref., 4-V-2013 (as larva), emerged on 3-VI-2013; 1♀, Chiisago, Kaminokuni, Hiyama, Hokkaido, 11-VI-2012 (as larva), emerged on 16-VI-2012.

On Conocephalum purpureorubrum : 1♀, Iwaobetsu, Shari, Hokkaido, 3-X-2011 (as larva), emerged on 26-V-2011; 1♀, Irisawai, Oshika, Nagano Pref., 29-IV-2011 (as larva), emerged on 2-VI-2011; 1♂, Horoman-kyo, Samani, Hokkaido, 30-IV-2021 (as larva), emerged on 25-V-2021; 1♀, Tanneso, Rubeshibetsu, Hiroo, Hokkaido, 2-X-2011 (as larva), emerged on 19-V-2011; 1♂1♀, Kanna-gawa, Nakatsugawa, Chichibu, Saitama Pref., 19-VIII-2002 (as larva), emerged on 5-V-2002; 1♀, Irisawai, Oshika, Nagano Pref., 20-IV-2011 (as larva), emerged on 2-VI-2011.

Diagnosis.

A medium-sized dark species (wing length 1.7-1.8 mm) having pruinose dark gray scutum, yellow scutellum, a black 1st flagellomere, dark maxillary palpus, dark halteres, and dark gray legs. Male epandrium inner-subdistally with a hypertrophied tubercle-like seta, and inner-basally with a comb comprising six or seven long fused tubercle-like setae. Larva mines the thallus of Conocephalum salebrosum , C. orientalis and C. purpureorubrum .

Description.

Adult male.

Head: (Fig. 56A-E ) Head yellow, with ocellar tubercle brown, back of head dark brown (Fig. 56C ). Antenna porrect, first flagellomere black, pedicel and scape yellow (Fig. 56B ). Arista subbasal, black, pubescent. Clypeus, face, gena, parafacial and postgena yellow (Fig. 56C ). Proboscis normal, yellow; palpus yellow, cylindrical. Chaetotaxy: Front orbitals three pairs; one ori directed inward; two ors directed upward (Fig. 56B ). Orbital setulae minute and erect, in a single row.

Thorax: Thorax subshiny. Scutum pruinose, dark gray, sometimes with very narrow terminal yellow band along posterior margin (Fig. 56D ). Scutellum light yellow with lateral corner narrowly grayish. Subscutellum yellow except brown posterior margin. Mediotergite, anatergite and katatergite dark gray (Fig. 56E ). Pleuron largely yellow, but notopleuron with narrow brown patch along ventral margin, and venters of propleuron, anepisternum, katepisternum, anepimeron, and meron dark brown (Fig. 56B ). Haltere dark gray. Calypter margin and hairs gray. Leg segments entirely brown; tibia and tarsus darker (Fig. 56A ). Chaetotaxy: Scutum with 1+3 dorsocentrals, shortened anteriorly (Fig. 56D ). Acrostichal setulae five or six pairs in two irregular rows. Wing: Wing length 1.8 mm, costa reaching M1 (Fig. 56A ). Length of ultimate section of vein M4 divided by penultimate section 1.5-1.6.

Abdomen: Abdomen dorsally subshiny brown; epandrium dark brown (Fig. 56E ). Genitalia: (Fig. 56G-K ) Epandrium rounded apically; posterior end of inner margin with a long, inward-curved tubercle-like seta; inner-anterior surface with a comb comprising six or seven fused long tubercle-like setae (rarely unfused in part), and with a separate long tubercle-like seta, which is located immediately beyond the dorsal-most tubercle-like seta of the comb and directed to different angle; inner-basal margin with a row of 1-3 small tubercle-like setae immediately outward from the comb (Fig. 56I ). Surstylus rounded, directed inwards, setose apically; with one long tubercle-like seta on posterior margin (Fig. 56I ). Cercus narrow, setose. Subepandrial sclerite dark with a pair of plate-like arms, dorsal lobe spatula-shaped, with one seta subapically (Fig. 56I ). Hypandrium slightly sclerotized along outer margin (Fig. 56G ). Postgonite bare, goose barnacle-shaped, rounded apically (Fig. 56H ). Phallophorus with deep incision below, articulated with phallapodeme, fused to epiphallus (Fig. 56G ). Basiphallus with dark broad plate-like sclerite on left side (Fig. 56G ). Hypophallus broad, membranous covered with microtrichia ventrally; lateral margins lightly sclerotized; medially with a pair of fused narrow sclerites (Fig. 56G, H ). Paraphallus membranous, wing-like; paraphalli spread laterally, jointed basally (Fig. 56H ). Mesophallus dark, cylindrical, widest basally, as long as distiphallus (Fig. 56H ). Distiphallus comprising one pair of stout tubules basally parallel to each other; covered by a membrane bearing several pairs of minute oval lateral sclerites; basal half composed of ventral dark subtriangular sclerite and weaker medial region; distal half cylindrical, pigmented, widening toward truncated, unpigmented apex (Fig. 56H ). Ejaculatory apodeme pale brown, fan-shaped with long stalk; sperm pump clear, with dark globular sclerites (Fig. 56I, J ).

Female (Fig. 56F ). Similar to male, but slightly larger and frons wider. Wing length 1.7 mm. Postabdomen: (Fig. 57A-C ) Oviscape dark brown, setigerous (Fig. 57A ). Tergite 10 trifurcate, laterally uniting narrow pleural sclerites (Fig. 57C ). Each cercus with two stout, apical, trichoid sensilla, 1/3 length of cercus (Fig. 57C ). Spermathecae semi-orbicular, with truncate proximal ends (Fig. 57B ).

Variation.

The morphology of the tubercle-like seta on the inner-distal margin of the male epandrium varied among localities from a simple seta to a flattened, basally enlarged acute spine. The relative position of a comb of tubercle-like setae and the separate tubercle-like seta neighboring the comb also varied among localities.

Japanese name.

Mihikari-jagoke-hamoguribae.

Host plants.

Conocephalum salebrosum , C. orientalis and C. purpureorubrum ( Conocephalaceae ).

Mine.

Larvae construct linear mines in the thallus in early instars, later entering the midrib, and pupate in the mines (Fig. 57E, F ).

Biological notes.

The habitats of this species are stream banks and mesic slopes in cool temperate deciduous forests dominated by Quercus crispula and Fagus crenata , riparian forests dominated by Cercidiphyllum japonicum (Fig. 57D ), and subalpine coniferous forests dominated by Abies spp. And Picea spp. It is sympatric with P. luna , P. brunofasciata , and P. luteola at some localities. Our rearing records suggest that this species is univoltine, and that adults emerge from overwintered pupae in spring.

Distribution.

Japan: Hokkaido, Honshu (Fig. 55 ).

Remarks.

This species was reported from Scotland by Strobl (1898), and later recorded from Austria ( Spencer 1972) and Taiwan ( Sasakawa 2008). It resembles P. tsukuyomi in having an almost wholly dark scutum and almost wholly yellow scutellum, but is distinguished by the color of the pedicel of the antenna (brown in P. alpicola ; yellow in P. tsukuyomi ) and by the number and arrangement of tubercle-like setae in a comb on the male epandrium (6 fused in P. alpicola ; 4 hand-like in P. tsukuyomi ). P. alpicola also resembles P. marchantiae , P. lanternaria , P. rebouliae , and P. conocephali in having dark brown scutum and yellow scutellum; it is distinguished from them by the absence of a small medial yellow mark on the posterior margin of the scutum, and by the absence of dark bands at the lateral margins of the yellow scutellum.

Figures

Figure 55. Locality records of three Phytoliriomyza species associated with Conocephalum spp.: P. bifasciata, P. alpicola and P. lanternaria.

Figure 56. Phytoliriomyza alpicola A-E male at Ikawa-toge A habitus B dorsal C frontal D dorsal E posterior F live female fly at Mitsumine-Jinja G-K male genitalia (G-J at Ikawa-toge K at Samani) G whole genitalia H phallic complex I epandrium J, K ejaculatory apodeme, ventral and lateral.

Figure 57. Female morphology and larval ecology of Phytoliriomyza alpicola sp. nov. A-C female postabdomen A oviscape and spermatheca B spermatheca C tergite 10 D habitat at Samani E, F mined thalli of Conocephalum salebrosum at Ikawa-toge).