Phytoliriomyza longifurcae 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

14. Phytoliriomyza longifurcae Kato sp. nov.

Figs 27 , 28

Material examined.

Holotype: Japan: 1♂ (MK-AG-a500), Sui, Anan, Tokushima Pref. (33.9044°N, 134.5391°E, 40 m asl), 30-III-2021 (as larva), emerged on 14-V-2021, NSMT-I-Dip 31968. Paratypes: Japan: 3♀ (MK-AG-a497-499), same data as holotype, emerged on 14-17-V-2021, NSMT-I-Dip 31969-31971.

Other material.

Japan: 4♂3♀, Kamihirayama, Tatsuyama, Tenryu, Hamamatsu, Shizuoka Pref., 7-XI-2010 (as larva), emerged on 18-28-IV-2011; 1♂1♀, Chiromo, Toyotama, Tsushima, Nagasaki Pref., 28-XI-2011 (as larva), emerged on 1-V-2011; 2♀, Kibune, Sakyo-ku, Kyoto Pref., 20-VI-2016 (as larva), emerged on 14-VII-2021.

Diagnosis.

A medium-sized species (wing length 1.5-1.6 mm) having a subshiny yellow scutum with a medial and two pairs of lateral black stripes, yellow 1st flagellomere, yellow maxillary palpus, yellow halteres, and yellow legs. Male epandrium inner-basally with a comb comprising six fused long tubercle-like setae, and inner-subdistally with an extremely elongated arm, which apically bears two dark, diverging, ventrally curved, tubercle-like setae. Larva mines the thallus of Reboulia hemisphaerica orientalis .

Description.

Adult male (Fig. 27A-E ).

Head: Head entirely yellow, with ocellar tubercle brown, and back of head dark brown (Fig. 27C ). 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. 27C ). Chaetotaxy: Front orbitals three pairs; one ori directed inward; two ors directed upward (Fig. 27B ). Orbital setulae minute and erect, in a single row.

Thorax: Thorax subshiny yellow. Scutum with medial black stripe on anterior 2/3, one pair of black suborbicular presutural spots confluent with the medial stripe, a pair of narrow black supra-alar stripes and a pair of wider black intra-alar stripes, which adjoin the pair of lateral presutural black suborbicular spots (Fig. 27D ). Mediotergite brown, anatergite yellow, katatergite brown (Fig. 27E ). 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. 27B ). Haltere yellow, while dorsal surface grayish yellow. Calypter margin and hairs gray. Leg segments yellow; tibia and tarsus darker. Chaetotaxy: Scutum with 1+3 dorsocentrals, shortened anteriorly (Fig. 27D ). Acrostichal setulae five pairs in two irregular rows. Wing: Wing length 1.5 mm, costa reaching M1 (Fig. 27A ). Length of ultimate section of vein M4 divided by penultimate section 1.6.

Abdomen: Abdomen dorsally subshiny yellow (Fig. 27E ). Genitalia: (Fig. 27H-L ) Epandrium dark brown, rounded apically; inner-lateral margin with a row of four short tubercle-like setae; inner-subdistal margin with an extremely elongated arm, bearing two, dark, ventrally curved, tubercle-like setae borne at wide angle (90-120°); inner-basal surface with a comb comprising 4-6 fused tubercle-like setae (Fig. 27K ). Surstylus lobate, directed inwards, setose apically, with one short tubercle-like seta subapically (Fig. 27K ). Cercus narrow, setose. Subepandrial sclerite with a pair of flat, pale, ventral lobes, each of which bearing a long seta subapically (Fig. 27K ). Hypandrium thin, slightly sclerotized along outer margin (Fig. 27H ). Postgonite bare, goose barnacle-shaped, cleft apically; upper lobe pointed apically (Fig. 27K ). Phallophorus with deep incision below (Fig. 27I ), articulated with phallapodeme, fused to epiphallus (Fig. 27J ). Basiphallus dorsally sclerotized with basal expanded lobes (Fig. 27I, J ). Hypophallus broad, lightly sclerotized, lateral lobes expanded anteriorly like wings, clear tubule emerging from median part (Fig. 27I ). Mesophallus dark, cylindrical, constricted subapically. Paraphalli membranous, rounded and expanded ventrally, bilaterally asymmetrical; right one larger than left one (Fig. 27I ). 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, flared clear apex (Fig. 27J ). Ejaculatory apodeme pale and fan-shaped with broad stalk; base wide to one side; sperm pump clear (Fig. 27L ).

Female (Fig. 27F, G ). Similar to male, but larger, frons wider. Wing length 1.6 mm. Postabdomen: (Fig. 28A, B ) Oviscape dark brown, setigerous (Fig. 28A ). Tergite 10 trifurcate, laterally uniting narrow pleural sclerites (Fig. 28B ). Each cercus with two stout, apical, trichoid sensilla, ¾ length of cercus (Fig. 28B ). Spermathecae semi-orbicular, with truncate proximal ends (Fig. 28A ).

Etymology.

The specific name (longus = long, furca = fork) refers to extremely elongated, apically biforked tubercle-like seta on the male epandrium.

Japanese name.

Sasumata-jingasagoke-hamoguribae.

Host plant.

Reboulia hemisphaerica orientalis ( Aytoniaceae ).

Mine.

Larvae construct linear-blotch mines in the thallus, and pupate in the mines (Fig. 28E, F ).

Biological notes.

The habitats of this species are rocky cliffs in warm temperate evergreen forests (Fig. 28D ). This species is rarer than P. argentifasciata , and sympatric with the latter in some localities. Our rearing records suggest that adults emerge from overwintered pupae in spring.

Distribution.

Japan: Honshu, Shikoku (Fig. 26 ).

Remarks.

This species resembles P. argentifasciata and P. nigroflava in having two pair of dark lateral bands on the scutum, and a yellow 1st flagellomere and yellow haltere; it is distinguished from P. argentifasciata by the black lateral stripes (inner bands reflecting silverly in sunlight in P. argentifasciata ), from P. nigroflava by the absence of an extremely extended, forked tubercle-like seta on the subdistal margin of the male epandrium.

Figures

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

Figure 27. Phytoliriomyza longifurcae sp. nov. A-E holotype male A habitus B lateral C frontal D dorsal E posterior F, G paratype female (MK-AG-a 497) F dorsal G lateral H-L male genitalia H epandrium, ventral I whole genitalia, ventral J, K phallic complex, ventral and lateral L ejaculatory apodeme, lateral.

Figure 28. Female morphology and larval / adult ecology of Phytoliriomyza longifurcae sp. nov. A, B female postabdomen A oviscape and spermatheca B tergite 10 C live fly D habitat at Sui E mined thalli of Reboulia hemisphaerica orientalis.