Phytoliriomyza argentifasciata Kato, 2022

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

13. Phytoliriomyza argentifasciata Kato sp. nov.

Figs 24 , 25

Material examined.

Holotype: Japan: 1♂ (MK-AG-a347), Ukawa, Tango, Kyotango, Kyoto Pref. (35.7102°N, 135.1623°E, 100 m asl), 5-III-2021 (as larva), emerged on 9-IV-2021 NSMT-I-Dip 31959. Paratypes: Japan: 1♀ (MK-AG-a462), same data as holotype, NSMT-I-Dip 31960; 2♀ (MK-AG-436, 441), Kibune, Sakyo-ku, Kyoto Pref., 24-VI-2011 (as larva), emerged on 12-VII-2011, NSMT-I-Dip 31961, 31961; 1♂ (MK-AG-478), Ryutosen, Higashi-sonogi, Nagasaki Pref., 30-IV-2017 (as larva), emerged on 31-V-2017, NSMT-I-Dip 31963; 1♀ (MK-AG-473), Kibune, Sakyo-ku, Kyoto Pref., 20-VI-2016 (as larva), emerged on 5-VII-2016, NSMT-I-Dip 31964; 1♂1♀ (MK-AG-456, 452), Han-yama, Yaku Is., Kumage, Kagoshima Pref., 29-III-2017 (as larva), emerged on 19-IV-2017, NSMT-I-Dip 31965, 31966; 1♀ (MK-AG-a204), Tachijami, Kume Is. Okinawa Pref., 20-III-2020 (as larva), emerged on 2-V-2020, NSMT-I-Dip 31967.

Other material.

Japan: 5♂3♀, Takasuka, Joso, Ibaragi Pref., 2-XI-2021 (as larva), emerged on 11-15-XII-2021; 1♀, Kuchisakamoto, Aoi-ku, Shizuoka Pref., 20-IX-1998 (as larva), emerged on 18-23-IX-1998; 1♀, Mt. Gozaisho, Komono, Mie Pref., 1-V-2001 (as larva), emerged on 25-V-2001; 3♂6♀, Ukawa, Tango, Kyotango, Kyoto Pref., 5-III-2021 (as larva), emerged on 2-8-IV-2021; 16♂10♀, Kibune, Sakyo-ku, Kyoto Pref., 24-VI-2011 (as larva), emerged on 12-VII-2011; 16♂25♀, Wadagawa-kyo, Kumanogawa, Shingu, Wakayama Pref., 7-VI-2021 (as larva), emerged on 17-VII-8-VIII-2021; 1♂1♀, Kibune, Sakyo-ku, Kyoto Pref., 23-IV-2021 (as larva), emerged on 2-6-V-2021; 6♂8♀, Ryugakyo, Yamashiro, Miyoshi, Tokushima Pref., 1-II-2014 (as larva), emerged on 24-IV-3-V-2014; 1♂1♀, Tazukawa-keikoku, Katsuura, Tokushima Pref., 30-III-2021 (as larva), emerged on 26-29-IV-2021; 3♂4♀, Sui, Anan, Tokushima Pref., 30-III-2021 (as larva), emerged on 14-17-IV-2021; 1♂2♀, Kurase-keikoku, Tanbara, Saijo, Ehime Pref., 2-II-2014 (as larva), emerged on 20-26-IV-2014; 1♀, Yasui-keikoku, Niyodogawa, Agawa, Kochi Pref., 27-II-2011 (as larva), emerged on 17-IV-2011; 1♂, Kinsakubaru, Amami, Kagoshima Pref., 4-VII-1999 (as larva), emerged on 25-VII-1999; 5♂11♀, Tachijami, Kume Is. Okinawa Pref., 20-III-2020 (as larva), emerged on 15-IV-8-V-2020.

Diagnosis.

A medium-sized species (wing length 1.5-1.9 mm) having subshiny yellow scutum with a medial and two pairs of lateral dark stripes; inner stripes with silvery reflection. Adults with yellow 1st flagellomere, yellow maxillary palpus, yellow halteres, and yellow legs. Male epandrium inner-laterally with a hand-like comb comprising four or five basally fused, long, tubercle-like setae. Larva mines the thallus of Reboulia hemisphaerica orientalis .

Description.

Adult male (Fig. 24A-E ).

Head: Head entirely yellow, with ocellar tubercle brown, and back of head dark brown (Fig. 24C ). Antenna porrect, yellow. Arista subbasal, brown, pubescent. Frons with brownish reflective pruinosity. Face, gena, parafacial, and postgena yellow. Proboscis normal, yellow; palpus yellow, cylindrical (Fig. 24C ). Chaetotaxy: Front orbitals three pairs; one ori directed inward; two ors directed upward (Fig. 24B ). Orbital setulae minute and erect, in a single row.

Thorax: Thorax subshiny yellow; in some geographic populations, background color grayish yellow (Fig. 24D ). Scutum with medial black stripe on anterior 2/3, one pair of gray suborbicular presutural spots confluent with the medial stripe, a pair of narrow black supra-alar stripes and a pair of wider gray intra-alar stripes, which adjoin the pair of lateral presutural gray suborbicular spots; the gray spots and stripes look silver in sunlight. Scutellum and subscutellum yellow (Fig. 24D ). Mediotergite brown, anatergite yellow, katatergite brown (Fig. 24E ). Pleuron largely yellow (the background color sometimes grayish in some localities); propleuron with small brown patch on mid-anterior corner; anepisternum with two small spots on anterior and posterior corners; anepimeron with a narrow brown patch on anterior corner; katepisternum and meron with brown patches on venter (Fig. 24B ). Haltere yellow, while dorsal surface grayish yellow. Calypter margin and hairs gray. Leg segments yellow; tibia and tarsus darker (Fig. 24A ). Chaetotaxy: Scutum with 1+3 dorsocentrals, shortened anteriorly (Fig. 24D ). Acrostichal setulae five pairs in two rows. Wing: Wing length 2.0-2.2 mm, costa reaching M1 (Fig. 24A ). Length of ultimate section of vein M4 divided by penultimate section 1.8-1.9.

Abdomen: Abdomen dorsally subshiny yellow (Fig. 24E ). Genitalia: (Fig. 24G-K ) Epandrium dark brown, rounded apically; inner-posterior surface with a long apically bifid tubercle-like seta; inner-lateral margin with a long tubercle-like seta, the tip of which is flattened and fan-shaped; inner-anterior surface with a finger-like comb comprising five basally fused tubercle-like setae (Fig. 24H ). Surstylus rounded, directed inwards, setose apically, with a single long, apically bifid, tubercle-like seta on posterior margin (Fig. 24H ). Cercus narrow, setose. Subepandrial sclerite with a pair of flat, pale, ventral lobes, each bearing a seta basally (Fig. 24J ). Hypandrium sclerotized along outer margin (Fig. 24G ). Postgonite bare and goose barnacle-shaped (Fig. 24J ). Phallophorus with deep incision below, articulated with phallapodeme, fused to epiphallus (Fig. 24K ). Basiphallus with a basally bilobed sclerite; each lobe expanded laterally. Hypophallus broad and membranous with lightly sclerotized margins, medially with a pair of fused linear sclerites (Fig. 24K ). Mesophallus dark, cylindrical, widest subbasally, 1.2 × longer than distiphallus. Distiphallus comprising one pair of stout tubules basally parallel to each other; basal half composed of lateral dark lanceolate sclerite and weaker medial region; distal half cylindrical, dorsally and laterally pigmented, with truncated, shortly flared unpigmented apex (Fig. 24K ). Ejaculatory apodeme pale and fan-shaped with broad stalk; base wide to one side; sperm pump clear (Fig. 24I ).

Female (Fig. 24F , 25C ). Similar to male, but larger, frons wider. Wing length 2.3 mm. Postabdomen: (Fig. 25A, B ) Oviscape dark brown, setigerous (Fig. 25A ). Tergite 10 trifurcate, laterally uniting narrow pleural sclerites (Fig. 25B ). Each cercus with two stout, apical, trichoid sensilla, 1/3 length of cercus (Fig. 25B ). Spermathecae semi-orbicular, with truncate proximal ends (Fig. 25A ).

Variation.

Background color of scutum and scutellum varies from yellow to grayish yellow, and the blackening is obvious in the Yaku Islands.

Etymology.

The specific name (argentus = silver, fascia = stripe) refers to silver stripes on the scutum, which are obvious in sunlight.

Japanese name.

Ginsuji-jingasagoke-hamoguribae.

Host plant.

Reboulia hemisphaerica orientalis ( Aytoniaceae ).

Mine.

Larvae construct digitate mines in the thallus, and pupate in the mine (Fig. 25E-I ).

Biological notes.

The habitats of this species are rocky cliffs in warm temperate evergreen forests (Fig. 25D ), and on the ground or on stone walls of temples, shrines and farms in rural ecosystems. Our rearing records suggest that this species is bivoltine, with adults emerging in spring and summer.

Distribution.

Japan: Honshu, Shikoku, Yaku Island, Amami-Oshima Island, Kume Island (Fig. 26 )

Remarks.

This species resembles P. dorsata , P. calcicola , P. longifurcae , P. nigroflava , and P. brunofasciata in having two pair of dark lateral bands on the scutum; it is distinguished from them by the silverly reflecting inner stripes (inner stripes black or gray in the other species), and by the extended, distorted tubercle-like seta on the subdistal margin of the male epandrium.

Figures

Figure 24. Phytoliriomyza argentifasciata sp. nov. A-E holotype male A habitus B lateral C frontal D dorsal E posterior F paratype female (MK-AG- 436) G-J male genitalia (G-J at type locality K at Kume Is.) G whole genitalia, ventral H epandrium, ventral I ejaculatory apodeme, lateral, J phallic complex, ventral K phallic complex, lateral.

Figure 25. Female morphology and larval ecology of Phytoliriomyza argentifasciata sp. nov. A, B female postabdomen A oviscape and spermatheca B tergite 10 C live fly at Kibune D habitat at Mt Oe E, F mined thalli of Reboulia hemisphaerica orientalis (E at Kibune I Kume Is.).

Figure 26. Locality records of three Phytoliriomyza species associated with Reboulia spp.: P. argentifasciata and P. longifurcae.