Phytoliriomyza phaeocerotis 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

39. Phytoliriomyza phaeocerotis Kato sp. nov.

Figs 74 , 75

Material examined.

Holotype: Japan: 1♂ (MK-AG-150), Muramatsu, Iwakura, Sakyo-ku, Kyoto Pref. (35.0931°N, 135.7900°E, 150 m asl), 16-XI-2017 (as larva on Notothylas temperata ), emerged on 2-I-2018, NSMT-I-Dip 32121. Paratypes: Japan: 2♂1♀ (MK-AG-a481, a483, a482), same data as holotype, emerged on 24-XI-2017-5-I-2018, NSMT-I-Dip 32122-32124; 1♀ (MK-AG-135), type locality, 22-IV-2016 (as larva on Phaeoceros carolinianus ), emerged on 10-V-2016, NSMT-I-Dip 32125; 1♀ (MK-AG-a10), type locality, 15-XI-2019 (as larva on Ph. carolinianus ), emerged on 18-XII-2019, NSMT-I-Dip 32126; 1♂ (MK-AG-a415), Inago, Shibakawa, Fujinomiya, Shizuoka Pref., 17-XII-2019 (as larva on Anthoceros punctatus ), emerged on 24-I-2020, NSMT-I-Dip 32127; 1♀ (MK-AG-a375), Mt. Gion, Takahashi, Okayama Pref., 9-X-2017 (as larva on Notothylas temperata ), emerged on 3-XI-2017, NSMT-I-Dip 32128; 1♀ (MK-AG-a11), Shodon, Kakeroma Is., Setouchi, Kagoshima Pref., 24-I-2019 (as larva on Ph. carolinianus ), emerged on 24-II-2019, NSMT-I-Dip 32129; 1♂ (MK-AG-a12), Minami-bokujo, Yonaguni Is. Yaeyama, Okinawa Pref., 5-III-2019 (as larva on Ph. carolinianus ), emerged on 2-IV-2019, NSMT-I-Dip 32130.

Other material.

Japan: On Phaeoceros carolinianus : 27♂52♀, Yudenno-sato, Sugegaya, Makinohara, Shizuoka Pref., 9-I-2018 (as larva), emerged on 2-26-II-2018; 2♂5♀, Megami, Makinohara, Shizuoka Pref., 10-XII-2017 (as larva), emerged on 30-I-7-II-2018; 11♂14♀, Muramatsu, Iwakura, Sakyo-ku, Kyoto Pref., 3-I-2018 (as larva), emerged on 19-I-23-II-2018; 18♂26♀, Shiozuka-kogen, Yamashiro, Miyoshi, Tokushima Pref., 5-XI-2017 (as larva), emerged on 29-XI-2017-9-II-2018; 6♂15♀, Shodon, Kakeroma Is., Setouchi, Kagoshima Pref., 23-I-2019 (as larva), emerged on 2-II-11-III-2019; 2♂, Minami-bokujo, Yonaguni Is. Yaeyama, Okinawa Pref., 5-III-2019 (as larva), emerged on 2-IV-2019.

On Notothylas temperata : 1♀, Inago, Shibakawa, Fujinomiya, Shizuoka Pref., 17-XII-2019 (as larva), emerged on 19-I-2020; 8♂17♀, Muramatsu, Iwakura, Sakyo-ku, Kyoto Pref., 16-XI-2017 (as larva), emerged on 20-XI-21-II-2017; 1♂, Mita-ike, Toyokura, Kasai, Hyogo Pref., 30-X-2017 (as larva), emerged on 17-XII-2017; 9♂10♀, Mt. Gion, Takahashi, Okayama Pref., 6-XI-2017 (as larva), emerged on 12-XI-5-XII-2017.

On Notothylas orbicularis : 1♂, Izuruhara, Tamura, Tochigi Pref., 2-XI-2021 (as larva), emerged on 10-XII-2021.

On Anthoceros punctatus : 1♂1♀, Inago, Shibakawa, Fujinomiya, Shizuoka Pref., 7-XII-2019 (as larva), emerged on 8-28-I-2020; 1♂1♀, Mita-ike, Toyokura, Kasai, Hyogo Pref., 30-X-2017 (as larva), emerged on 28-29-XI-2017.

Diagnosis.

A small species (wing length 1.2-1.5 mm) that has a pruinose gray scutum and scutellum, brown 1st flagellomere, yellow maxillary palpus, brown halteres, and yellow legs. Male epandrium inner-laterally with a short tubercle-like seta. Distiphalli elongated, tapering toward apex, more than 2 × longer than the phallapodeme. the larvae mine thalli of hornworts belonging to the following genera: Notothylas , Phaeoceros and Anthoceros .

Description.

Adult male (Fig. 74A-E ).

Head: Head entirely pale yellow, with ocellar tubercle dark brown, and back of head dark brown excluding margins (Fig. 74C ). Antenna porrect; first flagellomere brown, pedicel and scape grayish yellow (Fig. 74B ). Arista subbasal, brown, pubescent. Frons brownish yellow, with reflective pruinosity. Face, gena, parafacial and postgena yellow. Proboscis normal, pale yellow; palpus pale yellow, ovate (Fig. 74C ). Chaetotaxy: Front orbitals three pairs; one ori directed inward; two ors directed upward (Fig. 74B ). Orbital setulae minute and erect, in a single row.

Thorax: Thorax subshiny, pale yellow. Scutum and scutellum pruinose gray (Fig. 74D ). Subscutellum pale yellow. Mediotergite dark gray, anatergite brown, and katatergite pale yellow (Fig. 74E ). Pleuron largely pale yellow; postpronotal lobe with anterior brown spot; propleuron with a small brown patch on mid-anterior corner; notopleuron with narrow brown patch on anterior-lower margin; anepisternum and anepimeron without brown spot; katepisternum and meron with large brown patches on venter (Fig. 74B ). Haltere grayish yellow, with stalk paler. Calypter margin and hairs gray. Leg segments brownish yellow with coxa pale yellow; femur of foreleg with narrow brown subdistal patch on frontal side; tibia and tarsus darker (Fig. 74A ). Chaetotaxy: Scutum with 1+3 dorsocentrals, shortened anteriorly (Fig. 74D ). Acrostichal seta absent. Wing: Wing length 1.2-1.3 mm, costa reaching M1 (Fig. 74A ). M4 disappears immediately before reaching wing margin. Length of ultimate section of vein M4 divided by penultimate section 1.8-2.5.

Abdomen: Abdomen dorsally subshiny yellowish brown; epandrium brown (Fig. 74E ). Genitalia: (Fig. 74G-L ) Epandrium rounded apically; posterior end of inner margin with one or two tubercle-like setae (Fig. 74G, I ). Surstylus small, ovate, membranous, without setae (Fig. 74I ). Cercus narrow, setose. Subepandrial sclerite with a pair of pale plate-like dorsal arms directed posteriorly and a pair of pale elongated plate-like ventral arms directed ventrally (Fig. 74I ). Hypandrium thin, slightly sclerotized along outer margin (Fig. 74G ). Postgonite bare, goose barnacle-shaped, pointed and cleft apically (Fig. 74H, J ). Phallophorus with shallow incision below, articulated with phallapodeme, connecting to asymmetric epiphallus (Fig. 74H, J, L ). Basiphallus supported by a pair of rod-like lateral sclerites (Fig. 74H ). Hypophallus membranous, centrally with a pair of narrow sclerites (Fig. 74G-J ). Paraphallus absent. Mesophallus cylindrical, dorsolaterally sclerotized, medially widest. Distiphallus is a fused tubule comprising one pair of elongated tubules, with dark shoehorn-shaped sclerites basally; the tubule pale, extremely elongated, longer than phallapodeme; easily unfolded in the course of dissection (Fig. 74G ). Ejaculatory apodeme pale, fan-shaped with short brown stalk and clear sperm pump (Fig. 74K ).

Female (Fig. 74F ). Similar to male, but larger, frons wider. Wing length 1.5 mm. Postabdomen: (Fig. 75A-C ) Oviscape dark brown, setigerous (Fig. 75B ). Tergite 10 cruciform, laterally uniting narrow pleural sclerites (Fig. 75C ). Each cercus with two stout, apical, trichoid sensilla, ca. same length as cercus (Fig. 75C ). Spermathecae semi-orbicular, with truncate proximal ends (Fig. 75A ).

Immatures. (Fig. 75D-G, L-Q ) At 3rd instar, larval body yellow and cylindrical. Mandibles paired, fused and strongly sclerotized, each with two teeth; left teeth larger than right teeth (Fig. 75D-G ). Mandibles confluent with short sclerotized hypopharyngeal sclerite, connecting to a pair of tentoropharyngeal sclerites; dorsal cornu broad and long, ventral cornu shorter. Puparium internal, slender, pale brown, with anterior spiracles elongated and protruded from epidermis of mined thallus (Fig. 75P-S ).

Etymology.

The specific name refers to its host plant genus Phaeoceros .

Japanese name.

Niwatsunogoke-hamoguribae.

Host plants.

Four hornwort species belonging to 3 families were recorded to be host plants: Phaeoceros carolinianus , Notothylas temperata ( Notothyladaceae ), and Anthoceros punctatus ( Anthocerotaceae ).

Mine.

Larvae construct linear-blotch mines in the thallus, and pupate in the mines (Fig. 75J-M, P-S ). The larvae occasionally also mine into sporophytes (Fig. 75P ).

Biological notes.

The main habitats of this species are the paddy fields that have not experienced land improvement projects or spraying with herbicides, as mentioned for P. ricciae (Fig. 75H, I ). These paddy fields harbor various Riccia species and hornwort species such as Phaeoceros carolinianus , Notothylas temperate, and Anthoceros punctatus after harvesting of rice. Another habitat of this species was lawny ground in horse pasturelands in Yonaguni Island, where Phaeoceros carolinianus grows among turf grasses (Fig. 75N, O ). Thus, this species is the only species among the Japanese bryophyte-associated Phytoliriomyza species that utilizes multiple genera of bryophytes. Our rearing records suggest that it is multivoltine.

Distribution.

Japan: Honshu, Shikoku, Kyushu, the Ryukyu Archipelago (Fig. 71 ).

Remarks.

This species resembles P. iriomotensis , P. ugetsu , and P. caerulescens in that having wholly dark scutum and yellow maxillary palpus; it is distinguished from them by the absence of tubercle-like setae on the surstylus of the male epandrium. This species resembles P. foliocerotis in that the distiphallus is extremely elongated, but it is distinguished from P. foliocerotis by its pruinose gray scutum and scutellum (shiny black in P. foliocerotis ). This species also resembles P. scotica in morphology of epandrium and in having an extremely elongated distiphallus ( Papp and Černý 2017); it is distinguished from the latter by the bare surstylus (distally setose in P. scotica Spencer) and the broad shoehorn-shaped sclerites on the basal distiphallus (sclerites narrow in P. scotica ).

Immature stages, but not adults, were reported from a hornwort, Megaceros vincentianus in Mexico by Hering (1966). Phytoliriomyza phaeocerotis sp. nov. (Fig. 75R ) and the Mexican species share the elongated anterior spiracles.

Figures

Figure 71. Locality records of three Phytoliriomyza species associated with hornworts: P. foliocerotis, P. megacerotis and P. phaeocerotis.

Figure 74. Phytoliriomyza phaeocerotis sp. nov. A-E holotype male A habitus B lateral C frontal D dorsal E posterior F paratype female (MK-AG-a 10), dorsal G-K male genitalia (G, H emerged from Notothylas temperata at type locality I emerged from Phaeoceros carolinianus at Kakeroma Is. J emerged from Notothylas temperata at Kibi-kogen K emerged from Anthoceros punctatus at Inago) G whole genitalia, ventral H, J phallic complex, lateral and ventral I epandrium, ventral K ejaculatory apodeme, lateral L phallic complex, lateral.

Figure 75. Female morphology and larval morphology / ecology of Phytoliriomyza phaeocerotis sp. nov. A-C female postabdomen A spermatheca B oviscape and spermatheca C tergite 10 D-G, larval morphology D posterior spiracle E anterior body F, G pharyngeal skeleton in lateral and ventral-lateral view H, I habitat at type locality H harvested rice field I Notothylas temperata thalli growing on soil after harvest of rice J-L mined thalli of Phaeoceros carolinianus at type locality M-Q habitat (M) thalli bearing sporophytes (N) and mined thallus (O) of P. carolinianus at Yonaguni Is., Black and white arrows i indicate larvae and puparia, respectively. Scale: 100 µm (A-C, E-G); 10 µm (D).