Research Article |
Corresponding author: Yoto Komeda ( kome123k123@gmail.com ) Academic editor: Petr Janšta
© 2018 Yoto Komeda, Toshiharu Mita, Kenzo Yamagishi.
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:
Komeda Y, Mita T, Yamagishi K (2018) Three new brachypterous species of Trimorus Förster (Hymenoptera, Scelionidae) from Japan. Journal of Hymenoptera Research 63: 15-32. https://doi.org/10.3897/jhr.63.23671
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Three new brachypterous species of Trimorus Förster, T. coriaceus sp. n., T. granulatus sp. n., and T. haniyasu sp. n. were described from Japan. Keys to species of Eastern Palearctic brachypterous Trimorus and Japanese male of Trimorus are provided.
Taxonomy, Teleasinae , East Asia
The genus Trimorus Förster, 1856 is one of the largest genus in Scelionidae, comprising 389 species (Johnson 2018). Among Scelionidae, the brachypterous females are somewhat common, especially of spider egg parasitoids. Females of Baeus Haliday, 1833 are always apterous, although males have developed wings. In Idris Föester, 1856, females of some species have shortened wings, however, others species are macropterous. Wing polymorphisms are reported in some heteropterous egg parasitoids (e.g. Gryonini Szabó, 1966 and Telenomini Thomson, 1860 (
Specimens examined in the present study have been deposited in collections of the Entomological Laboratory of Kyushu University, Fukuoka, Japan (
Photos were taken by Canon MP-E65mm micro lens mounted on Canon EOS 60D, combined by CombineZM, and processed in GIMP 2.8.14. SEM images were taken by Hitachi S-3000N.
Morphological terminology and measurements follow
Female. Frons coriaceous. A2–4 same length. Mandible tridentate; teeth almost same length. Mesoscutum flat, densely punctate–imbricate. Mesoscutellum flat, imbricate. Postacetabulum imbricate–smooth. Fore and hind wings reaching posterior edge of T1. T1 with slightly developed horn; T3 coriaceous with dense setae.
Female (n = 3): Length = 0.88–0.90 mm (m = 0.89).
Color (Fig.
Head. FCI = 1.18–1.21 (m = 1.19); LCI = 1.50–1.62 (m = 1.55); DCI = 1.81–1.90 (m = 1.84) HW/IOS = 1.60–1.65 (m = 1.62); head about 1.3 times as wide as mesosoma (HW/TSL = 1.27–1.33, m = 1.31). Frons (Fig.
Mesosoma. Pronotal suprahumeral sulcus foveolate; epomial carina incompletely present; cervical pronotal area imbricate with dense setae; lateral pronotal area rugulose–smooth. Mesoscutum (Fig.
Metasoma. T1 about 0.7 times as long as T1+T2 length (T1W/T1+T2L = 0.59–0.87, m = 0.70), longitudinally costate; T1 horn slightly producing. T2 longitudinally costate anteriorly, coriaceous with dense setae posteriorly; basal depressions on T2 present; lateral patch of T2 absent; T3 (Fig.
Male. Unknown.
Material examined. Holotype: Aichi pref.: Kita–Shitara dist., Shitara town, Uradani (Beech forest), alt. 900m, 18–24. VII. 1994, K. Yamagishi leg., 1♀ (EmT) [
Japan (Honshu: Aichi).
The species name refers to the sculpture of frons and metasoma.
Among eastern Palearctic Trimorus species, this species is similar to T. amesis Kozlov & Kononova, 2001 and T. mirandus Kozlov & Kononova, 2001 in having shortened wings that at most reach posterior margin of mesosoma. However, it differs from T. amesis in small body size (T. coriaceus about 0.9 mm, whereas T. amesis is about 1.4 mm), antenomere length ratio (A2, A3, A4 are same length, A4 is about 2 times longer than A5, A5 and A6 are same length in T. coriaceus; A2 and A3 are same length, A4 is about 0.8 times shorter than A3 and 3.4 times longer than A5, A5 and A6 are same length in T. amesis) and central keel (not reaching anterior ocellus in T. coriaseus; complete in T. amesis), and from T. mirandus in sculpture of frons, mesoscutellum, and T3 (frons is coriaceous (Fig.
Head globular. Frons granulate. Eyes small. Mandible subtridentate, with anterior and posterior large teeth and median small tooth. Mesoscutum and mesoscutellum flat, granulate. Postacetabulum granulate–smooth. In female, A2 and A3 longest among A2–6; fore and hind wings short, narrow, beyond anterior edge of metasoma; T1 without horn; T3 shallowly punctate with dense setae. In male, A5 about 2.3 times as long as wide, about 1.5 times as long as tyloid; fore and hind wings long, narrow, exceeding to apical metasoma; T3 weakly punctate–smooth.
Female (n = 3): Length = 0.90–0.95 mm (m = 0.93).
Color (Fig.
Head globular. FCI = 1.13–1.16 (m = 1.14); LCI = 1.28–1.35 (m = 1.32); DCI = 1.48–1.52 (m = 1.50); HW/IOS = 1.33–1.40 (m = 1.37); head about 1.3 times as wide as mesosoma (HW/TSL = 1.24–1.32, m = 1.29). Frons (Fig.
Mesosoma. Pronotal suprahumeral sulcus sulcate–foveolate; epomial carina weakly present; cervical pronotal area granulate with dense setae; lateral pronotal area smooth. Mesoscutum (Fig.
Metasoma. T1 about 0.6 times as long as T1+T2 length (T1W/T1+T2L = 0.50–0.59, m = 0.55), longitudinally costate. T2 longitudinally costate in anterior, shallowly punctate with dense setae in posterior; basal depressions on T2 present; lateral patch of T2 absent. T3 (Fig.
Male (n = 3): Length = 0.93–1.00 mm (m = 0.95). FCI = 1.17–1.27 (m = 1.22); LCI = 1.32–1.36 (m = 1.34); DCI = 1.55–1.73 (m = 1.64); HW/IOS = 1.42–1.46 (m = 1.45); HW/TSL = 1.17–1.27 (m = 1.24). Central keel (Fig.
Holotype: Fukuoka pref.: Fukuoka city, Mt. Tachibana, 2. X. 1993, H. Honda leg., 1♀ (YPT) [
Japan (Kyushu: Fukuoka).
The species name refers to the sculpture on frons and mesoscutum.
Among eastern Palearctic Trimorus species, the female of this species is similar to T. amesis Kozlov & Kononova, 2001 and T. mirandus Kozlov & Kononova, 2001 in shortened wings at most reaching posterior margin of mesosoma. But it differs from T. amesis in small body size (T. granulatus about 0.9 mm; T. amesis about 1.4 mm) and sculpture of T3 (shallowly punctate in T. granulatus, coriaceus in T. amesis), and from T. mirandus in sculpture of frons, mesoscutellum and T3 (frons and mesoscutellum are granulate (Fig.
Frons shallowly punctate. Mandible subtridentate, with anterior and posterior large teeth and median small tooth. Mesoscutum and mesoscutellum densely deeply punctate. Postacetabulum rugulose–densely deeply punctate. T3 deeply punctate. In female, A3 longest among A2–6; mesoscutum and mesoscutellum flat; fore and hind wings reaching apical margin of T3; T1 without horn. In male, A5 about twice as long as wide and about 1.8 times as long as tyloid; mesoscutum and mesoscutellum convex; fore wing far exceeding to apical mesosoma; hind wing exceeding to apical mesosoma.
Description. Female (n = 2): Length = 1.83–2.00 mm.
Color (Fig.
Head. FCI = 1.09–1.13; LCI = 1.62–1.74; DCI = 1.83–1.89; HW/IOS = 1.66–1.76; head about 1.2 times as wide as mesosoma (HW/TSL = 1.18–1.28). Frons (Fig.
Mesosoma. Pronotal suprahumeral sulcus foveolate; epomial carina incompletely present; cervical pronotal area rugulose–densely deeply punctate without setae; lateral pronotal area smooth–rugose. Mesoscutum (Fig.
Metasoma. T1 about 0.6 times as long as T1+T2 length (T1W/T1+T2L = 0.56–0.57), longitudinally costate. T2 longitudinally costate; basal depressions on T2 present; lateral patch of T2 present, with dense setae. T3 (Fig.
Male (n = 3): Length=1.88–1.98 mm (m = 1.93); A1–2 (Fig.
Holotype: Aichi pref.: Kita–Shitara dist., Shitara town, Uradani (Beech forest), alt. 900m, 13–19. VI. 1994, K. Yamagishi leg., 1♀ (YPT) [
Japan (Honshu: Aichi).
The species named after Haniyasu, a Japanese god of the soil.
Among eastern Palearctic Trimorus species, the female of this species is similar to T. mirificus Kozlov & Kononova, 2000 and T. angulator Kozlov & Kononova, 2000 in shortened wings that reach T3. However, it differs from both species in sculpture of frons (shallowly punctate in T. haniyasu; along to central keel smooth and other part costate in T. mirificus; dorsally reticulate, ventrally smooth T. angulator), mesoscutum (densely and deeply punctate in T. haniyasu; reticulate in T. mirificus and T. angulator) and T3 (deeply punctate in T. haniyasu; costate and granulate in T. mirificus; reticulate in T. angulator). In male, antenomeres about twice as long as wide in T. haniyasu, but about 5 times as long as wide in T. mirificus.
(“Brachypterous” means shortened wing reaching or not beyond posterior margin of T3 in this key.)
1 | Body length more than 1.7 mm; wings reaching T3 | 2 |
– | Body length less than 1.4 mm; wings shorter, at most reaching posterior margin of mesosoma | 4 |
2 | Frons (Fig. |
T. haniyasu sp. n. |
– | Sculptures of frons and T3 different from above; mesoscutum reticulate | 3 |
3 | T1 horn present; frons and T3 strigate | T. mirificus Kozlov & Kononova, 2000 |
– | T1 horn absent; frons and T3 reticulate | T. angulator Kozlov & Kononova, 2000 |
4 | Central keel completely present, reaching anterior ocellus | T. amesis Kozlov & Kononova, 2000 |
– | Central keel incomplete, not reaching anterior ocellus | 5 |
5 | Frons, mesoscutellum, and T3 smooth; mesoscutellum wide: SW/SL about 3.3; T3 wider: T3W/T3L about 1.5 | T. mirandus Kozlov & Kononova, 2000 |
– | Frons, mesoscutellum and T3 sculptured; mesoscutellum not so wide: SW/SL less than 2.6; T3W/T3L about 1.2 | 6 |
6 | Head (Fig. |
T. coriaceus sp. n. |
– | Head (Fig. |
T. granulatus sp. n. |
(Male of T. butus Kononova & Kozlov, 2001, T. calvus Miyazaki, 1979, T. coriaceus, T. fulviclavatus Miyazaki, 1979, T. nasutus Kononova & Kozlov, 2001, T. nipponensis Masner & Muesebeck, 1968, T. striatissimus Miyazaki, 1979 and T. viktori Kononova, 2001 are unknown.)
1 | Mandible tridentate, with almost same length teeth (body mainly black-dark brown; notaulus present, expanding to half level of mesoscutum; T3 weakly coriaceous) | T. nigrigaster Miyazaki, 1979 |
– | Mandible subtridentate, with anterior and posterior large teeth and median small tooth (or bump) | 2 |
2 | Antennomeres elongated: A5L more than 3.5 times as long as A5W | T. laticlypeatus Miyazaki, 1979 |
– | Antennomeres shortened: A5L less than 2.5 times as long as A5W | 3 |
3 | Body length less than 1 mm. (frons (Fig. |
T. granulatus sp. n. |
– | Body length greater than 1.8 mm. (frons (Fig. |
T. haniyasu sp. n. |
We express our cordial thanks to Dr. T. Hirowatari and members of the Entomological Laboratory, Kyushu University for their invaluable advice during this study. The authors wish to thank two anonymous reviewers for comments on earlier version of this paper. Our thanks are also due to Mr. H. Honda for the collection of many specimens. This is a contribution from the Entomological Laboratory, Kyushu University, Fukuoka (Ser. 7, No. 61).
Checklist of brachypterous Trimorus