Phytoliriomyza luna 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

19. Phytoliriomyza luna Kato sp. nov.

Figs 37 , 38

Material examined.

Holotype: Japan: 1♂ (MK-AG-a401), Yashajin-toge, Minami-arupusu, Yamanashi Pref. (35.6327°N, 138.3519°E, 1110 m asl), 10-XII-2016 (as larva on C. salebrosum ), emerged on 8-IV-2017, NSMT-I-Dip 31997. Paratypes: Japan: 1 ♀ (MK-AG-512), same data as holotype; emerged on 8-IV-2017 NSMT-I-Dip 31998; 1♂ (MK-AG-a245), Horoka, Kamishihoro, Hokkaido, 7-VI-2010 (as larva on C. purpureorubrum ), emerged on 21-VI-2010, NSMT-I-Dip 31999; 1♂ (MK-AG-493), Aizankei, Kamikawa, Hokkaido, 4-X-2011 (as larva on C. salebrosum ), emerged on 11-V-2012, NSMT-I-Dip 32000; 1♀ (MK-AG-591), Yachi, Kawaba, Gunma Pref., 14-IV-2012 (as larva on C. purpureorubrum ), emerged on 4-V-2012, NSMT-I-Dip 32001; 1♀ (MK-AG-a362), Mt. Kiyosumi, Kamogawa, Chiba Pref.2, 31-III-2021 (as larva on C. salebrosum ), emerged on 23-IV-2021, NSMT-I-Dip 32002.

Other material.

Japan: On Conocephalum salebrosum : 3♂3♀, Aizankei, Kamikawa, Hokkaido, 10-IV-2011 (as larva), emerged on 6-11-VI-2011; 2♀, Mt. Upepesanke, Shihoro, Kamishihoro, Hokkaido, 7-VI-2010 (as larva), emerged on 15-18-VI-2010; 1♂1♀, Horoka, Kamishihoro, Hokkaido, 7-VI-2010 (as larva), emerged on 21-26-VI-2010;; 1♂, Tanneso, Rubeshibetsu, Hiroo, Hokkaido, 2-X-2011 (as larva), emerged on 3-V-2012; 4♂10♀, Yashajin-toge, Minami-arupusu, Yamanashi Pref., 10-XII-2016 (as larva), emerged on 26-III-11-IV-2016; 1♀, Nakabusa-onsen, Azumino, Nagano Pref., 9-VI-2013 (as larva), emerged on 29-IV-2013; 1♂2♀, Shirahone-onsen, Matsumoto, Nagano Pref., 15-X-2013 (as larva), emerged on 18-25-IV-2013.

On Conocephalum purpureorubrum : 1♂1♀, Yachi, Kawaba, Gunma Pref., 15-X-2013 (as larva), emerged on 4-10-IV-2014; 1♂2♀, Haccho-toge, Ogano, Chichibu, Saitama Pref., 14-XI-2010 (as larva), emerged on 27-III-16-IV-2010.

Diagnosis.

A large yellow species (wing length 2.7-2.9 mm) having pruinose yellow scutum with a medial and a pair of dark brown lateral stripes, entirely yellow scutellum, black 1st flagellomere, yellow maxillary palpus, yellow halteres, and yellow legs. Male epandrium inner-distally with a long tubercle-like seta, and inner-basally with a comb consisting of 7-9 long fused tubercle-like setae. Larva mines the thallus of Conocephalum salebrosum and C. purpureorubrum .

Description.

Adult male (Fig. 37A-E ).

Head: Head entirely yellow including ocellar tubercle and back of head (Fig. 37C ). Antenna porrect, first flagellomere black, pedicel and scape brown (Fig. 37B ). Arista subbasal, pubescent. Face, gena, parafacial and postgena yellow. Proboscis normal, yellow; palpus yellow, cylindrical (Fig. 37C ). Chaetotaxy: Front orbitals three pairs; one ori directed inward; two ors directed upward (Fig. 37B ). Orbital setulae minute and erect, in a single row.

Thorax: Thorax subshiny. Scutum yellow with a black medial stripe on anterior 2/3, one pair of black suborbicular presutural patches confluent with the medial stripe, and a pair of wide black bands (i.e., fused complex of intra-alar and supra-alar stripes) on anterior 7/8, which is confluent with the presutural patches (Fig. 37D ). Scutellum and subscutellum entirely yellow (Fig. 37D ). Mediotergite brown, but katatergite yellow, anatergite yellow with distal brown patch (Fig. 37E ). Pleuron yellow with brown patches on propleuron centrally and on distal margins of anepisternum, katepisternum, and meron (Fig. 37B ). Haltere yellow. Calypter margin and hairs gray. Leg segments yellow; tibia and tarsus darker (Fig. 37B ). Chaetotaxy: Scutum with 1+3 dorsocentrals, shortened anteriorly (Fig. 37D ). Acrostichal setulae 8-10 pairs in two irregular rows. Wing: Wing length 2.7 mm, costa reaching M1 (Fig. 37A ). Length of ultimate section of vein M4 divided by penultimate section 1.3.

Abdomen: Abdomen dorsally subshiny yellow; epandrium dark brown (Fig. 37E ). Genitalia: (Fig. 37G-J ) Epandrium rounded apically; posterior end of inner margin with one tubercle-like seta; inner-anterior surface with a comb comprising 7-9 fused long tubercle-like setae (rarely unfused in part) and an irregular row of several (4-7) small tubercle-like setae immediately outward from the comb (Fig. 37I ). Surstylus rounded, directed inwards, setose apically, with one (rarely 2 or 3) tubercle-like seta ventrally (Fig. 37I ). Cercus narrow, setose. Subepandrial sclerite V-shaped (Fig. 37I ). Hypandrium slightly sclerotized along outer margin (Fig. 37H ). Postgonite bare, rounded apically, cleft subapically (Fig. 37K ). Phallophorus with deep incision below, articulated with phallapodeme, fused to epiphallus (Fig. 37H ). Basiphallus dorsally sclerotized (Fig. 37H ). Hypophallus broad, membranous, with one pair of dark narrow long sclerites along margins; medially with one pair of fused linear sclerites (Fig. 37G, H ). Mesophallus dark, cylindrical, widest subbasally, 3/5 shorter than distiphallus, tapering distally (Fig. 37H ). Distiphallus comprising one pair of stout tubules parallel to each other at base; basal half composed of ventral dark subrectangular sclerite and weaker medial region; distal half cylindrical, dorsally pigmented; apex truncated, shortly flared unpigmented (Fig. 37H ). Ejaculatory apodeme pale brown, fan-shaped with short broad stalk, stout base, and clear sperm pump (Fig. 37J ).

Female (Fig. 37F ). Similar to male, but larger, frons wider, black lateral stripes of scutum wider and almost confluent with medial stripe. Wing length 2.3 mm. Postabdomen: (Fig. 37L-N ) Oviscape dark brown, setigerous (Fig. 37L ). Tergite 10 cruciform, laterally uniting narrow pleural sclerites (Fig. 37M ). Each cercus with two stout, apical, trichoid sensilla, ¼ length of cercus (Fig. 37M ). Spermathecae semi-orbicular, with truncate proximal ends (Fig. 37N ).

Variation.

The number of tubercle-like setae in a comb in the male genitalia varies from 7 to 9, but the variation did not involve in a geographical cline.

Etymology.

The specific name refers to the moon; a clear, rounded, yellow pattern on the scutum was likened to a full moon.

Japanese name.

Meigetsu-jagoke-hamoguribae.

Host plants.

Conocephalum salebrosum and C. purpureorubrum ( Conocephalaceae ).

Mine.

(Fig. 38C, D ) Larvae construct linear mines in the thallus in early instars, later entering the midrib, and pupate in the mines.

Biological notes.

The habitats of this species are stream banks and mesic slopes in subalpine coniferous forests dominated by Abies spp., Picea spp., and Betula spp. (Fig. 38A-B ). This species was sympatric with P. nigroflava in some localities. Our rearing records suggest that this species is univoltine, and that adults emerge from overwintered pupae in spring.

Distribution.

Japan: Hokkaido, Honshu, Shikoku (Fig. 39 ).

Remarks.

The characteristics of this species and the following three related species ( P. izayoi , P. chichibuensis , and P. caliginosa ) coincide with those of Lemurimyza described by Spencer (1965). These four new species can be distinguished from the four species previously placed in Lemurimyza species ( P. enormis (Spencer, 1963), P. admirabilis (Spencer, 1965), P. dorsata , and P. pectoralis (Becker, 1908)) by the following characteristics: halteres yellow; maxillary palpus yellow; 1st flagellomere black; scutum with one pair of dark lateral bands.

This species also resembles P. islandica and P. bornholmensis recorded respectively from Iceland and Denmark; it is distinguished from them by the lateral black bands terminating before reaching the scutellum (lateral black bands confluent with scutellum in the other two species); scutellum entirely yellow (scutellum with dark bands on lateral margins in the other two); male epandrium with a comb of 7-9 tubercle-like setae (6 in P. islandica , 8 in P. bornholmensis ); male epandrium with one tubercle-like seta on middle inner surface (1 or 2 setae on middle inner margin in P. islandica ; 3 setae along inner margin in P. bornholmensis ); basal half of distiphallus curved outward and with weaker medial region (basal half of distiphallus curved outward and without weaker medial region in P. islandica ; angular and with weaker medial region in P. bornholmensis ).

This species resembles P. pacifica reported from North America but is distinguished by having a single pair of lateral bands on the scutum (two pairs of lateral stripes in P. pacifica ), the number of tubercle-like setae on the male epandrium (7-9 in P. luna ; 6 in P. pacifica ), and position of the isolated tubercle-like seta on the inner surface of the male epandrium (distal margin in P. luna ; basal inner surface in P. pacifica ).

Among Japanese species, this species resembles P. izayoi , P. chichibuensis , and P. caliginosa , in size and in having a pair of dark broad lateral bands on scutum; it is distinguished from them by the wholly yellow scutellum (scutellum with dark bands on lateral margins in the other species).

Figures

Figure 37. Phytoliriomyza luna sp. nov. A-E holotype male A habitus B lateral C frontal D dorsal E posterior F paratype female (MK-AG- 512), dorsal G-K male genitalia G whole genitalia, ventral and lateral H phallic complex, lateral I epandrium, ventral J ejaculatory apodeme, lateral K postgonite L-N female postabdomen at Aizankei L oviscape and spermatheca M tergite 10 N spermatheca.

Figure 38. Larval ecology of Phytoliriomyza luna sp. nov. A habitat at Mt. Shirouma B, C mined thalli of Conocephalum salebrosum (B Jozankei C Yashajin-toge).

Figure 39. Locality records of three Phytoliriomyza species associated with Conocephalum spp.: P. luna, P. izayoi, P. chichibuensis and P. caliginosa.