Research Article |
Corresponding author: Yi-Chang Liao ( ycliaopsyllids@gmail.com ) Corresponding author: Man-Miao Yang ( mmy.letsgall@gmail.com ) Academic editor: Igor Malenovský
© 2020 Gene-Sheng Tung, Yi-Chang Liao, Daniel Burckhardt, Man-Miao Yang.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Tung G-S, Liao Y-C, Burckhardt D, Yang M-M (2020) Trioza turouguei sp. nov. (Hemiptera, Psylloidea, Triozidae), a new psyllid species from Taiwan inducing pea-shaped stem galls on Cinnamomum osmophloeum (Lauraceae), with notes on its galling biology. ZooKeys 958: 91-106. https://doi.org/10.3897/zookeys.958.52977
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Trioza turouguei sp. nov., a new species of jumping plant lice (Hemiptera, Triozidae) from Taiwan, is described and illustrated based on adults and immatures. The latter induce pea-shaped galls on the stems of Cinnamomum osmophloeum Kaneh. (Lauraceae). The gall phenology of the new species is described. A list of species of Triozidae associated with Cinnamomum in the Old World is provided. The following nomenclatorial acts are proposed: Trioza inflata Li, 1992 = Trioza xiangicamphorae Li, 1992, syn. nov.; Siphonaleyrodes formosanus Takahashi, 1932, stat. rev., is removed from synonymy with Trioza cinnamomi (Boselli, 1931).
Asia, jumping plant lice, Oriental region, phenology, Siphonaleyrodes, Sternorrhyncha, taxonomy
Jumping plant lice or psyllids (Hemiptera, Sternorrhyncha, Psylloidea) are phloem-feeding insects that are highly host specific, especially during the immature stages (
The first studies on the psyllid fauna of Taiwan are from foreign researchers made during the first half of the 20th century (
Cinnamomum osmophloeum Kaneh. is a tree species endemic to Taiwan, growing at low elevations around the island. The tree species has some economic potential for its essential oils in the leaves (
Here, we formally name the species on C. osmophloeum as Trioza turouguei sp. nov., describe its adults and immatures, discuss its relationships to other psyllids developing on Cinnamomum, and provide information on the life cycle and gall phenology.
Psyllids were collected by sweeping and directly searching on Cinnamomum osmophloeum. The material is dry mounted or preserved in 70% and 99% ethanol. Some specimens were cleared in 15% potassium hydroxide and examined in orange oil or glycerol or permanently mounted in Canada balsam on a slide. Information on galls was taken in the field and from herbarium specimens.
Specimens from following institutions were examined: Entomological Museum, China Agricultural University, Beijing, China (
Photographs of most morphological characters were taken with a compound microscope (Leica DM 750) equipped with a digital camera (Canon EOS 600D). Images of the forewings of adults were taken with a stereomicroscope (Leica MZ 125) equipped with a digital camera (Olympus EP-1). The photographs were montaged using focus stacking software (Helicon Focus, Helicon Soft). The morphological terminology follows
The life cycle and gall phenology were observed at the Huisun Experimental Forest Station (24°05'24"N, 121°02'03"E; 660–370 m a.s.l.) from January to December 1996. We selected eight trees of C. osmophloeum to record the phenology of the plants and the galls induced by T. turouguei sp. nov. The terminology of gall development follows
Holotype
: Taiwan • ♂; Taichung City, Shalien Lane; 24°11'20"N, 120°55'06"E; 20 Dec. 2018; Y. C. Liao leg.; Cinnamomum osmophloeum;
(not included in type series). Galls on herbarium specimens of Cinnamomum osmophloeum, Taiwan: • Nantou Co., Meiyuunshan; 8 Oct. 1935;
Forewing vein M < 2.0 times vein M1+2, cell cu1 value > 2.0, cell m1 value > 1.8. Genal processes massive, blunt apically. Male paramere, in profile, with almost straight anterior margin; apex pointed. Distal segment of aedeagus shorter than paramere, apical third inflated, spoon-shaped. Female proctiger truncate apically.
Adults
(Figs
Structure. Body large, length from anterior head margin to tip of folded forewing 5.4–6.8 mm; covered in long fine setae. Head (Fig.
Male terminalia (Fig.
Measurements (range, mean ± SD) in mm (5 males, 5 females). Body length (including forewing) ♂ 5.38–6.38, 6.04 ± 0.33; ♀ 6.00–6.81, 6.60 ± 0.27. Head width ♂ 0.83–0.95, 0.89 ± 0.05; ♀ 0.85–0.98, 0.93 ± 0.04. Vertex length ♂ 0.25–0.30, 0.28 ± 0.02; ♀ 0.28–0.30, 0.30 ± 0.01. Genal cone length ♂ 0.23–0.25, 0.25 ± 0.01; ♀ 0.28–0.30, 0.28 ± 0.01. Antenna length ♂ 1.23–1.58, 1.43 ± 0.11; ♀ 1.38–1.55, 1.46 ± 0.07. Metatibia length ♂ 0.88–0.95, 0.93 ± 0.03; ♀ 0.88–0.98, 0.92 ± 0.03. Forewing length ♂ 4.44–5.31, 5.02 ± 0.31; ♀ 5.25–5.88, 5.63 ± 0.19.
Fifth instar immatures
(Figs
Measurements (range, mean ± SD) in mm (5 immatures). Body length 2.63–2.83, 2.76 ± 0.08. Head width 0.85–0.93, 0.88 ± 0.03. Antenna length 0.43–0.48, 0.45 ± 0.02. Metatibiotarsus length 0.60–0.68, 0.65 ± 0.03. Forewing pad length 1.35–1.45, 1.41 ± 0.04. Caudal plate length 0.85–1.00, 0.97 ± 0.07. Caudal plate width 1.45–1.55, 1.52 ± 0.04. Circumanal ring width 0.38–0.44, 0.41 ± 0.02.
Named after the Chinese common name of the host plant, 土肉桂, transliterated as “turouguei“; to be treated as a noun in the nominative singular standing in apposition.
Taiwan.
Cinnamomum osmophloeum Kaneh. (Lauraceae). Leaf and flower buds of C. osmophloeum appear in late April. Young leaves grow from late May to late June and flowers bloom from early June to August. Fruits ripen from September to November.
Trioza turouguei sp. nov. is univoltine and induces pea-shaped galls (Fig.
Based on the examination of relevant types (
Trioza turouguei sp. nov. differs from the other species associated with Cinnamomum as indicated in the following keys. In particular, it is diagnosed by details of the male and female terminalia and the multilayered circumanal ring in the immature.
Old World Triozidae associated with Cinnamomum (Lauraceae). Plant names marked with asterisk are confirmed hosts as defined by
Psylloid species | Host species | Gall type | Distribution | Reference |
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Siphonaleyrodes formosanus Takahashi, 1932, stat. rev. | *Cinnamomum reticulatum Hayata | pit galls | Taiwan |
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Trioza camphorae Sasaki, 1910 | *Cinnamomum camphora (L.) J. Presl | pit galls | India ?, Japan, Taiwan, China |
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Trioza camphoricola Li, 1993 | Cinnamomum camphora (L.) J. Presl | ? | China |
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Trioza cinnamomi (Boselli, 1931) | *Cinnamomum doederleinii Engl., *C. loureiroi Nees, *C. tenuifolium (Makino) Sugim., *C. yabunikkei H. Ohba, Neolitsea aciculata (Blume) Koidz. | pit galls | Japan, Korea (the record from Taiwan is erroneous as T. cinnamomi was described from Japan and not Taiwan) |
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Trioza exoterica Yang, 1984; = Trioza parthenoxyli Yang & Li, in Li & Yang, 1985 | Cinnamomum porrectum (Roxb.) Kosterm., *Cryptocarya chinensis (Hance) Hemsl. (Lauraceae) | leaf curling gall | China, Taiwan |
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Trioza guipicircularis (Li, 2011) = Trioza circularis Li, 1993 nec Froggatt, 1901; primary homonym | Cinnamomum austrosinense H. T. Chang | closed gall (not pit gall as recorded in |
China |
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Trioza hangzhouica (Li, 1994) | Cinnamomum tenuifolium (Makino) Sugim. | unknown | China |
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Trioza inflata Li, 1992, = Trioza xiangicamphorae Li, 1992, syn. nov. | Cinnamomum iners Reinw. ex Blume, C. verum J. Presl | ? | China |
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Trioza macularicamphorae Li, 1992 | Cinnamomum iners Reinw. ex Blume | ? | China |
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Trioza magnicamphorae Li, 1993 | Cinnamomum camphora (L.) J.Presl | ? | China |
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Trioza monri Burckhardt, 2018 = Trioza laqueus minor Kandasamy, 1986 | Cinnamomum sp. | ? | India |
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Trioza nigricamphorae Li, 1993 | Cinnamomum camphora (L.) J.Presl | ? | China |
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Trioza turouguei sp. nov. | *Cinnamomum osmophloeum Kaneh. | mung-pea like stem gall | Taiwan | this paper |
Trioza pseudocinnamomi Li, 1993 | Cinnamomum burmanni (Nees & T. Nees) Blume | ? | China |
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Adults
(Adults of Siphonaleyrodes formosanus are unknown)
1 | Metatibia with 1+3 apical spurs | 2 |
– | Metatibia with mostly 1+2 apical spurs | 3 |
2 | Genal processes shorter than vertex along midline. Vein Rs of forewing short, concavely curved towards fore margin | Trioza exoterica Yang |
– | Genal processes longer than vertex along midline. Vein Rs of forewing long, sinuous | Trioza nigricamphorae Li |
3 | Forewing vein M > 2.0 times vein M1+2 | 4 |
– | Forewing vein M < 2.0 times vein M1+2 | 5 |
4 | Genal processes about as long as vertex along midline. Vein Cu of forewing longer than Cu1b. China | Trioza hangzhouica (Li) |
– | Genal processes distinctly shorter than vertex along midline. Vein Cu of forewing shorter than Cu1b. India | Trioza monri Burckhardt |
5 | Forewing with cell cu1 value > 2.0 | 6 |
– | Forewing with cell cu1 value < 1.9 | 9 |
6 | Genal processes slender, subacute apically. Forewing with cell m1 value < 1.8 | 7 |
– | Genal processes massive, blunt apically. Forewing with cell m1 value > 1.8 | 8 |
7 | Forewing widest in apical third; apex subacute | Trioza cinnamomi (Boselli) |
– | Forewing widest in the middle; apex narrowly rounded | Trioza macularicamphorae Li |
8 | Paramere, in profile, with basal lobe anteriorly; apex blunt. Female proctiger with digitiform apical process | Trioza magnicamphorae Li |
– | Paramere, in profile, with almost straight anterior margin; apex pointed. Female proctiger truncate apically | Trioza turouguei sp. nov. |
9 | Genal processes around two thirds of vertex length measured along midline | Trioza camphoricola Li |
– | Genal processes as long as or longer than vertex along midline | 10 |
10 | Male proctiger short, weakly produced posteriorly, without very long conspicuous setae along hind margin. Paramere, in profile, distinctly narrowed in apical third | 11 |
– | Male proctiger long, strongly produced posteriorly, with long conspicuous setae along hind margin. Paramere, in profile, not strongly narrowed in apical third. | 12 |
11 | Forewing narrowly rounded apically; vein Rs of forewing relatively long, almost straight, slightly turned towards fore margin apically | Trioza camphorae Sasaki |
– | Forewing pointed apically; vein Rs short, concavely curved towards fore margin | Trioza inflata Li |
12 | Forewing 2.3 times as long as broad. Paramere, in profile, lamellar, truncate apically | Trioza guipicircularis Li |
– | Forewing 2.9 times as long as broad. Paramere, in profile, lanceolate, subacute apically | Trioza pseudocinnamomi Li |
Immatures
(Immatures of Trioza camphoricola, T. guipicircularis, T. hangzhouica, T. inflata, T. macularicamphorae, T. magnicamphorae, T. monri, T. nigricamphorae and T. pseudocinnamomi are unknown)
1 | Body relatively slender, > 1.6 times as long as wide | 2 |
– | Body relatively broad, < 1.5 times as long as wide | 3 |
2 | Body margin with several rows of sectasetae……….. | Siphonaleyrodes formosanus Takahashi |
– | Body margin with a single row of sectasetae | Trioza exoterica Yang |
3 | Outer circumanal ring consisting of 2–5 rows of pores | Trioza turouguei sp. nov. |
– | Outer circumanal ring consisting of a single row of pores | 4 |
4 | Dorsal outline subcircular, 1.1 times as long as wide. Tarsal arolium circular | Trioza camphorae Sasaki |
– | Dorsal outline broadly oval, 1.2 times as long as wide. Tarsal arolium triangular | Trioza cinnamomi (Boselli) |
Trioza turouguei sp. nov. is characterized by the induction of pea-shaped galls on stems of its host. Stem galls induced by psyllids are much rarer than those on leaves (
Cinnamomum osmophloeum, the host of Trioza turouguei sp. nov., has a scattered distribution in Taiwan growing in broad-leaved forests. Its conservation status is “Vulnerable” in the International Union for Conservation of Nature (IUCN) Red List (
We are grateful to Sheng-Feng Lin and Hsuan Chang for their help in the field, to Fasheng Li and Wanzi Cai (