22. Phytoliriomyza caliginosa Kato sp. nov.

Fig. 43

Material examined.

Holotype: Japan: 1♂ (MK-AG-a403), Kuki, Owase, Mie Pref. (34.0297°N, 136.2506°E, 270 m asl), 1-IV-2009 (as larva), emerged on 9-IV-2009, NSMT-I-Dip 32017. Paratypes: Japan: 1♀ (MK-AG-a224), same data as holotype, emerged on 11-IV-2009, NSMT-I-Dip 32018; 1♀ (MK-AG-a250), Asahi-daki, Shuzenji, Izu, Shizuoka Pref., 7-III-2012 (as larva), emerged on 28-III-2012, NSMT-I-Dip 32019; 1♂1♀ (MK-AG-a238, a239), Yunokuchi-onsen, Kiwa, Kumano, Mie Pref., 9-13-IV-2019 (as larva), emerged on 22-IV-2019, NSMT-I-Dip 32020, 32021; 1♂1♀ (MK-AG-a237, a390), Mt. Kosho, Asakura, Fukuoka Pref., 11-IV-2010 (as larva), emerged on 24-IV-2010, NSMT-I-Dip 32022.

Other material.

Japan: 1♂1♀, Mt. Nokogiri, Kyonan, Awa, Chiba Pref., 24-I-2012 (as larva), emerged on 24-IV-8-V-2012 1♂1♀, Asahi-daki, Shuzenji, Izu, Shizuoka Pref., 7-III-2012 (as larva), emerged on 28-III-1-IV-2012; 3♂3♀, Tamaki-gawa, Totsugawa, Yoshino, Nara Pref., 9-III-2014 (as larva), emerged on 26-III-9-IV-2014; 2♂1♀, Wabuka, Kushimoto, Wakayama Pref., 4-III-2012 (as larva), emerged on 26-III-12-IV-2012; 1♂2♀, Kibune, Sakyo-ku, Kyoto Pref., 1-III-2011 (as larva), emerged on 25-III-3-IV-2011; 2♂, Yasukawa-keikoku, Tanabe, Wakayama Pref., 9-VII-2012 (as larva), emerged on 16-21-IV-2002; 1♂1♀, Takinohai, Kozagawa, Wakayama Pref., 13-IV-2014 (as larva), emerged on 2-15-V-2014; 1♀, Yoshiwa, Hatsukaichi, Hiroshima Pref., 30-V-2014 (as larva), emerged on?-V-2014; 2♀, Mt. Ryuso, Aoi, Shizuoka Pref., 13-X-2015 (as larva), emerged on 14-IV-2015; 1♂, Shinkawa-keikoku, Kirishima, Kagoshima Pref., 31-III-2017 (as larva), emerged on 16-IV-2017.

Diagnosis.

A large yellow species (wing length 2.1-2.3 mm) having pruinose dark brown scutum with an obscure oval yellow pattern extending from the mid-posterior margin to the scutellum, a black 1st flagellomere, yellow maxillary palpus, yellow halteres, and yellow legs. Male epandrium inner-laterally with a long tubercle-like seta and inner-basally with a comb comprising eight or nine long fused tubercle-like setae. Larva mines the thallus of Conocephalum orientalis .

Description.

Adult male (Fig. 43A-E).

Head: Head entirely yellow including ocellar tubercle and back of head (Fig. 43C). Antenna porrect, first flagellomere black, pedicel and scape brown (Fig. 43B). Arista subbasal, pubescent. Face, gena, parafacial and postgena yellow. Proboscis normal, yellow; palpus yellow, cylindrical (Fig. 43C). Chaetotaxy: Front orbitals three pairs; one ori directed inward; two ors directed upward (Fig. 43B). Orbital setulae minute and erect, in a single row.

Thorax: Thorax pruinose. 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 and the medial stripe (Fig. 43D). Scutellum yellow with lateral margins brown. The yellow patch ranging from posterior scutum to scutellum oblong and ill-defined. Subscutellum yellow except for brown posterior half. Mediotergite brown, but katatergite yellow, anatergite yellow with distal brown patch (Fig. 43E). Pleuron yellow with brown patches on propleuron centrally and on distal margins of notopleuron, anepisternum, katepisternum and meron (Fig. 43B). Haltere yellow. Calypter margin and hairs gray. Leg segments yellow; tibia and tarsus darker (Fig. 43A). Chaetotaxy: Scutum with 1+3 dorsocentrals, shortened anteriorly. Acrostichal setulae eight or nine pairs in two irregular rows. Wing: Wing length 2.2 mm, costa reaching M1 (Fig. 43A). Length of ultimate section of vein M4 divided by penultimate section 1.1.

Abdomen: Abdomen dorsally subshiny grayish yellow; epandrium dark brown (Fig. 43E). Genitalia: (Fig. 43G-J) Epandrium rounded apically; inner-lateral surface with one long tubercle-like seta; inner-anterior surface with a comb comprising eight or nine fused long tubercle-like setae and an irregular row of several (4-5) small tubercle-like setae immediately outward from the comb (Fig. 43I). Surstylus rounded, directed inwards, setose apically, with one tubercle-like seta on posterior margin (Fig. 43I). Cercus narrow, setose. Subepandrial sclerite V-shaped in a posterior view (Fig. 43I). Hypandrium slightly sclerotized along outer margin (Fig. 43G). Postgonite bare, goose barnacle -shaped, rounded apically (Fig. 43H). Phallophorus with deep incision below, articulated with phallapodeme, fused to epiphallus (Fig. 43H). Basiphallus with broad pale plate on left side and lightly sclerotized anterodorsal margin (Fig. 43H). Hypophallus broad, membranous, and bilaterally asymmetrical; with a dark narrow sclerite on right side; medially with a pair of fused linear sclerites (Fig. 43G, H). Mesophallus dark, cylindrical, widest subbasally, as long as distiphallus, tapering distally (Fig. 43H). Distiphallus comprising one pair of stout tubules basally parallel to each other; basal half composed of dark short cuneiform sclerite and weaker medial region; distal half cylindrical, dorsally pigmented; with truncated, shortly flared unpigmented apex (Fig. 43H). Ejaculatory apodeme pale brown, with fan-shaped blade and broad stalk; base wide to one side; sperm pump clear (Fig. 43J).

Female (Fig. 43F). Similar to male. Wing length 2.3 mm. Postabdomen: (Fig. 43K-L) Oviscape dark brown, setigerous (Fig. 43K). Tergite 10 cruciform, laterally uniting narrow pleural sclerites. Each cercus with two stout, apical, trichoid sensilla, ¼ length of cercus (Fig. 43L). Spermathecae semi-orbicular, with truncate proximal ends (Fig. 43K).

Variation.

The number of tubercle-like setae in a comb in the male genitalia varies from 8 to 9, but the variation does not involve a geographic cline.

Etymology.

The specific name (caliginosus = misty) refers to the obscure yellow mark on the scutum, which resembles a dim spring moon.

Japanese name.

Oborozuki-jagoke-hamoguribae.

Host plant.

Conocephalum orientalis ( Conocephalaceae).

Mine.

Larvae construct linear mines in the thallus in early instars, later entering the midrib, and pupate in the mines (Fig. 43M).

Biological notes.

The habitats of this species are stream banks and mesic slopes in warm temperate evergreen forests dominated by Castanopsis cuspidata and Quercus sessilifolia . This species was sympatric with P. pallidofasciata and P. conocephali in some localities. Our rearing records suggested that this species was univoltine; it overwinters as a pupa and the adult emerged in spring.

Distribution.

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

Remarks.

This species resembles P. islandica and P. bornholmensis recorded respectively from Iceland and Denmark; it is distinguished from P. islandica by the number of tubercle-like setae in a comb of the male epandrium (8-9 in P. caliginosa, 6 in P. islandica), and from P. bornholmensis by the form of the sclerite of the basal distiphallus (short cuneiform in P. caliginosa; long triangular in P. bornholmensis). This species also resembles P. igniculus and P. chichibuensis in the yellow oblong obscure pattern of the scutum; it is distinguished from P. igniculus by the absence of a pair of lateral brown patches on the 2nd abdominal tergite (present in P. igniculus), and from P. chichibuensis by the number of tubercle-like setae in a comb of the male epandrium (8-11 in P. caliginosa; 6-8 in P. chichibuensis).