Phyllonorycter bilobae T. Liu, 2022

Lu, Ming, Li, Wei, Liu, Peng & Liu, Tengteng, 2022, Leaf-mining moths of the genus Phyllonorycter Hübner (Lepidoptera: Gracillariidae: Lithocolletinae) associated with Malvaceae in China, with descriptions of one new species, Zootaxa 5205 (3), pp. 265-280 : 267-271

Phyllonorycter bilobae T. Liu , sp. n.

( Figs 1–2 , 7–8 , 11–12 , 15–20 )

ậ担杆潜áḍ [Chinese name]

Diagnosis. The new species is similar to Phyllonorycter conista ( Meyrick, 1911) and P. anchistea which also feed on species of Malvaceae in the Oriental region and Ethiopian region south, but can be distinguished by the following characters. In the new species, the male genitalia are asymmetrical ( Figs 7–8 ), the female eighth sternite is covered with dense spines, the ostium bursae is located at the posterior edge of the eighth abdominal segment ( Figs 11–12 ). However, in P. conista and P. anchistea , the male genitalia are both symmetrical ( Kumata 1993: Figs 17–18 , De Prins & Kawahara 2012: Figs 243–245), and the ostium bursae are both located at the posterior edge of the VII abdominal segment and the eighth sternite lacks spines ( Kumata 1993: Figs 19–20 , De Prins & Kawahara 2012: Fig. 334).

Type material. Holotype, ♂, CHINA: Shandong, Jinan, Yaoxiang Forest Farm, 36.334°N, 117.114°E, 700 m, 7.x.2018, mine on leaves of Grewia biloba , emerged 9–13.x.2018 (indoors), leg. Tengteng Liu and Zhongfeng Jiang, field no. LTT00492, genitalia slide no. LM0079, SDNU. Ent 003568.

Paratypes (all China): 10♂, 5♀, other data same as holotype, SDNU. Ent 001615, SDNU. Ent 003567, SDNU. Ent 003569 (LM0080 ♀), SDNU.Ent006442, SDNU.Ent006444 (LM0081 ♀), SDNU.Ent006827–29, SDNU. Ent006836–38,SDNU.Ent006847 (LM0116 ♂), SDNU.Ent006856, SDNU.Ent012169, SDNU.Ent012171 ; 2♂, same data as holotype, except 24.viii.2018, emerged 18–20.ix.2018 (indoors), field no. LTT00470, SDNU. Ent 012129, SDNU. Ent 012131 ; 1♂, Shandong, Jinan, Mt. Zhufeng , 36.716°N, 117.154°E, 310 m, 3.ix.2021, mine on leaves of G. biloba , emerged 14.ix.2021 (indoors), leg. Ming Lu, field no. LU00156 , SDNU. Ent 024684 ; 2♂, Shandong, Jinan, Changqing District, Mt. Liantai , 36.441°N, 116.932°E, 338 m, 28.vi.2021, mine on leaves of G. biloba , emerged 7–8.vii.2021 (indoors), leg. Ming Lu, field no. LU00065 , SDNU. Ent 021706 (LM0117 ♂), SDNU. Ent 023657 ; 1♂, Shandong, Jinan, Mt. Fohui , 36.627°N, 117.047°E, 300 m, 15.ix.2020, mine on leaves of G. biloba , leg. Tengteng Liu, field no. LTT00972, SDNU. Ent 021023 ; 5♂, 1♀, Shandong, Zibo, Yiyuan County, Luya Reservoir , 36.268°N, 118.010°E, 470 m, 11.ix.2021, mine on leaves of G. biloba , emerged 26.ix.2021 (indoors), leg. Ming Lu, field no. LU00159 , SDNU. Ent 024677 (LM0114 ♂), SDNU. Ent 024678, SDNU. Ent 028154 (LM0074 ♀), SDNU. Ent 028155, SDNU. Ent 028156 (LM0073 ♂), SDNU. Ent 028157 ; 2♂, 1♀, Shandong, Linyi, Mt. Meng , 35.528°N, 117.823°E, 300 m, 15.ix.2021, mine on leaves of G. biloba , leg. Ming Lu, field no. LU00178 , SDNU. Ent 024674 (LM0115 ♂), SDNU. Ent 024675–76 ; 1♂, 2♀, Shandong, Yantai, Mt. Kunyu , 37.292°N, 121.740°E, 400 m, 17.vii.2017, mine on leaves of G. biloba var. parviflora , emerged 21.vii.2017 (indoors), leg. Tengteng Liu and Zhenquan Gao, SDNU. YT170705, SDNU.YT1705.2, SDNU.YT170705.4 ; 1♂, Shandong, Yantai, Mt. Kunyu, Shuiliandong , 37.267°N, 121.763°E, 300 m, 7.vii.2019, mine on leaves of G. biloba , emerged 14.viii.2019 (indoors), leg. Encui Wang and Tengteng Liu, field no. WEC00120, SDNU. Ent 012159 ; 10♂, 3♀, Shandong, Binzhou, Mt. Heban , 36.771°N, 117.721°E, 280 m, 24.ix.2021, mines on leaves of G. biloba , emerged 28.iv.2021 (indoors), leg. Ming Lu, field no. LU00191 , SDNU. Ent 028140–41, SDNU. Ent 028142 (LM0059 ♂), SDNU. Ent 028143 (LM0060 ♀), SDNU. Ent 028144–49, SDNU. Ent 028150 (LM0112 ♀), SDNU. Ent 028151; SDNU. Ent 028191 (LM0069 ♀) ; 1♀ , Shaanxi, Xian, Huyi , 34.016°N, 108.586°E, 815 m, 29.vii.2021, mine on leaves of G. biloba , leg. Tengteng Liu, field no. LTT01035, SDNU. Ent 024120 .

Adult ( Figs 1–2 ). Including aestival and autumnal forms, but also have transitional forewing patterns caused by different darkening degrees.

Aestival form ( Fig. 1 ). Forewing length: 2.3–3.2 mm (HT = 3.2 mm). Frons white. Piliform scales tuft on vertex white mixed with black. Labial palpus white, blackish fuscous ventrally. Antenna slightly shorter than forewing, black on dorsum of scape, white ventrally, flagellum yellowish brown with black ring. Dorsal thorax yellowish brown. Forewing ground color yellowish brown, markings beige, with black scales edged basally, boundaries unclear, one transverse fascia, four costal and two dorsal strigulae; first costal strigula at basal 1/3 of forewing, triangular, oblique; black scales between base of costa and first costal strigulae; transverse fascia located in middle of forewing, angular, twice broader at dorsum than at costa; second costal strigula at basal 2/3, angular, smaller than first strigula, vertical; third costal strigula at distal 3/4, linear, with a row of black scales, vertical; fourth costal strigula near apex, rod-shaped, about twice as large as first, vertical; first dorsal strigula at 1/4, with black scales near dorsal margin anteriorly; second dorsal strigula opposite to second costal strigula, similar; black scales scattered along termen; cilia grayish white on dorsum, basal half blackish gray and distal half grayish white on termen. Hindwing and cilia uniformly gray. Legs white; foreleg grayish black ventrally; mid tibia with three black twill stripes, tarsus with two wide black rings; hind tibia with one black spot, tarsus with three wide black rings. Abdomen dark brown dorsally, grayish white ventrally; genital segments with yellow tuft.

Autumnal form ( Fig. 2 ). Similar to aestival form, but darker in color. Tuft on head blackish gray. Ventral labial palpus covered with grayish black scales. Dorsal thorax covered with taupe scales. Forewing ground color grayish brown, markings blurred.

Male genitalia ( Figs 7–8 ). Tegumen basal 2/3 nearly equal in width, distal 1/3 tapered, weakly sclerotized, truncated distally. Transtilla strongly sclerotized, about 1/4 length of valva. Valvae asymmetrical, same in length, almost as long as tegumen; left valva wider than right, concaved in middle of apex, dorsal margin arc-shaped, with a curved spine at apex, about 1/6 length of valva, ventral margin straight, ventro-apex triangular; setae dense near apex, sparser towards middle, almost absent at base; right valva slender, strip-shaped, basal 1/3 of dorsal margin slightly convex, distal 1/4 narrowed, subapex slightly enlarged and curved towards ventral margin, pointed distally, setae concentrated in distal 1/3. Vinculum weak. Saccus narrow, triangular, rounded distally. Phallus about 2/3 length of valva, gradually narrowed, with a lamellar hook apically. Eighth sternite almost oval, slightly concave in middle distally.

Female genitalia ( Figs 11–12 ). Papillae anales densely covered with short setae. Posterior apophyses wide at base, enlarged at middle, tapered to apex; anterior apophyses about 1/5 length of posterior apophyses, extending from antero-lateral angle of segment VIII and reaching middle of segment VII; eighth sternite covered with dense spines. Ostium bursae located at posterior border of segment VIII. Antrum tubular, weakly sclerotized. Ductus bursae slender, membranous; ductus seminalis membranous from posterior 1/3 of ductus bursae. Corpus bursae rounded, signum with one pair of small odontoid processes, connected at base and opposite to each other.

Biology. The mine of the new species is similar to other Phyllonorycter species. It is located on the underside of the leaf. The early mine is a whitish flat blotch ( Fig. 15 ), then expands into a circle. In the later stage, the mine begins to be slender and becomes a tentiform blotch with 3–7 folds on the lower epidermis ( Figs 16–17 ). The larva primarily consumes spongy parenchyma and in the late stage it consumes palisade parenchyma. Clear white spots appear on the upper epidermis at this time ( Figs 18–19 ), so the mine can be easily traced from the upper side of the leaf. The frass was scattered in the mine in the early stage, and was accumulated on the side of the mine in the later stage. Early mines can be traced in early June, and mature mines can be collected in late June. Mines of different instars can be collected from July to September indicating a generation overlapping or an asynchronous hatching of eggs. Mature mines can still be collected in early October and one adult emerged in mid-October indoor. Therefore, it is speculated that this species has at least two generations per year and may overwinter as pupae or adults.

Host plants. Grewia biloba var. biloba and G. biloba var. parviflora (Malvaceae) .

Distribution. China (Shaanxi, Shandong).

Etymology. The specific name is derived from the species name of the host plant.

Figures

FIGURES 1–6. Adults of Phyllonorycter spp. (All from China). 1–2, P. bilobae, sp. n.: 1, male, paratype, aestival form, SDNU.Ent023657, Jinan; 2, male, holotype, autumnal form, SDNU.Ent003568, Jinan; 3–6, P. issikii: 3, male, aestival form, SDNU.Ent023629, Yantai; 4, female, aestival form, SDNU.Ent023626, Yantai; 5, female, SDNU.Ent021694, Zibo; 6, male, SDNU.Ent021695, Zibo.

FIGURES 7–10. Male genitalia of Phyllonorycter spp. 7–8, P. bilobae sp. n.; 7, holotype, slide no. LM0079; 8, paratype, slide no. LM0073, rectangular box indicating the convex on basal 1/3 of dorsal margin; 9, P. issikii, slide no. LM0057; 10, P. issikii, slide no. LM0055, rectangular box indicating the basal 1/3 of dorsal margin slightly convex.

FIGURES 11–12. Female genitalia of Phyllonorycter bilobae, sp. n. 11, paratype, slide no. LM0060, arrow indicating the opening of antrum; 12, paratype, slide no. LM0074; 12a, corpus bursae and signum.

FIGURES 15–20. Biology of Phyllonorycter bilobae, sp. n. 15–19, leaf mines; 15, early mine, underside view; 16–17, mine with folded epidermis, underside view; 18–19, deformed leaf with clear white spots on the upper epidermis; 20, host plant Grewia biloba var. parviflora. Arrows indicating the mines in Figs 15–19.