Bruchidius siliquastri is a bruchid beetle that was recently described by Delobel in 2007 based on specimens emerged from pods of Cercis siliquastrum L. (Fabaceae) in southern France in 2003. This species was found to be conspecific with specimens bred in China from an unidentified species of Cercis. Based on the foregoing, the author of description has supposed an eastern Asian origin for this species (Kergoat et al., 2007). Later B. siliquastri was found in many European countries. Currently the species is also known from Hungary in 2005 (Kergoat et al., 2007), Slovakia in 2006 (Kollár et al., 2009), Bulgaria in 2009 (Stojanova et al., 2011), Gibraltar and Spain (Yus Ramos et al., 2009), Belgium (Hanssens, 2009), Czech Republic (Šefrová, 2010), Monaco (Ponel et al., 2011), Serbia in 2011 (Gavrilović and Savić, 2013), Turkey in 2012 (Hizal and Parlak, 2013), Germany in 2012 (Rheinheimer and Hassler, 2013), Britain (Barclay, 2014), Crimea (Martynov and Nikulina, 2015), Italy (Yus Ramos and Bocci, 2017) and Romania (Pintilioaie et al., 2018).
The bruchid species, B. siliquastri Delobel supposed an eastern Asian origin (Kergoat et al., 2007), has recently been uploaded and identified by domestic Korean bloggers. However, they did not conduct a precise identification. In addition, the authors were able to observe some life cycle of this species from the spring of 2022 on the Cercis chinensis Bunge (Fabaceae) planted on the campus of Sunchon National University. In this study, we present new ecological data of a bruchid beetle, B. siliquastri Delobel from Korea.
Materials and Methods
Examined specimens were collected on the seeds of the Cercis chinensis Bunge (Fabaceae) planted on the campus of Sunchon National University (SCNU) in the spring of 2022. Some larvae into the seedpods were reared in the laboratory. Specimens were taken pictures with a digital USB 3.0 microscope camera (DMC5400) that is attached to Leica M125 Stereo microscope. The pictures were stacked by using the LAS software (version X). Specimens examined in this study are deposited in insect collections of the Department of Plant Medicine in SCNU.
In addition, since this bruchid species can be identified from the photos of adults, we reviewed photos uploaded by bloggers and used them as distribution data.
The following abbreviations were used throughout the text: GG - Gyeonggi-do, JB - Jeollabuk-do, and JN - Jeollanam-do.
Results
Taxonomic account
Family Chrysomelidae Latreille, 1802
Subfamily Bruchinae Latreille, 1802
Tribe Bruchini Latreille, 1802
Genus Bruchidius Schilsky, 1905
Bruchidius Schilsky, 1905, in Kuester, Käf. Eur. 41, p. e & B. [Type species: Bruchus quinqueguttatus Olivier, 1795]
Sparteus Bridwell, 1946, J. Wash. Acad. Sci. 36: 55. [Type species: Bruchus ater Masham, 1802 = Bruchus villosus Fabricius, 1792]
Bruchidius siliquastri Delobel, 2007 박태기콩바구미(신칭)
Bruchidius siliquastri Delobel, 2007, Ann. soc. entomol. Fr. (n.s.) 43(3): 266. [TL: France - Hérault]
Diagnosis. (Fig. 1) (Male) Body length 2.4 - 2.7 mm. Head short with bulging eyes. Frons lacks a carina. Pronotum very convex, wider at the base, while the elytra are short; its third stria possesses a small tooth. Hind femora incrassate with a carinate mesoventral margin. Hind tibiae apically widened with strong both dorsomesal and ventral carinae. Abdominal sternite 5 emarginate, as long as the 4th sternite. First sternite with a patch of short erect setae basally. Pygidium subcircular, with its apex turned under. Genitalia with a median lobe with two strong hinged sclerites at the apical part and 2 - 3 short thick spines in the middle of the inner sac; lateral lobes more widened at the apex and provided with very long setae
(Female) Body length 3.0 - 3.3 mm (small sized population 2.3 - 2.4 mm). Last abdominal sternite not emarginate and longer than its 4th. Pygidium narrower than the male's, bearing a pair of foveae. Genitalia with a large toothed sclerite in the bursa copulatix.
Specimen examined. 5 3 exs. (8 m ales a nd 4 5 females), campus of SCNU, Suncheon, JN, 2-18.v.2022, on the seedpods of Cercis chinensis Bunge (Fabaceae), Y. Jeong; 27 exs. (17 males and 10 females), ibid, 8.viii.2022, sweeping on the trees of C. chinensis Bunge, Y. Jeong; [Blogger’s photo data] Seoul, 22.v.2020 (https://blog.naver.com/acekds03/); Wanju, JB, 21. vi.2020 (https://blog.naver.com/onl1207/); Mt. Gwanggyoan, Suwon, GG, 30.viii.2021 (https://blog.naver.com/moonyel1/); Anyang, GG, 22.v.2022 (https://blog.naver.com/hihwanzz/).
Distribution. Korea (new record - GG, JB, JN), China (probably originate), Europe (introduced) (Pintilioaie et al., 2018).
Biological notes.
(Host plants) Larval feeding in the seeds of Cercis siliquastrum L. (Fabaceae) in Europe and C. chinensis Bunge observed in this study (Fig. 2).
(Life cycle observed in the field) As shown in Table 1, this bruchid species overwintered as adult stage and lays eggs on the seedpods of Cercis chinensis Bunge in early May. Their larvae feed on seeds in the seedpods from mid-May to early August.
(Parasitoids) Pteromalidae - Dinarmus acutus (Thomson), D. italicus (Masi), Mesopolobus sp.; Eupelmidae - Eupelmus confusus Al khatib, E. urozonus Dalman; Eurytomidae - Bruchophagus sp., unidentified Eulophidae, unidentified Ceraphronidae, unidentified Braconidae (Pintilioaie et al., 2018).