Tricosa metacuneola (Eggers) Cognato & Smith & Beaver, 2020

Cognato, Anthony I., Smith, Sarah M. & Beaver, Roger A., 2020, Two new genera of Oriental xyleborine ambrosia beetles (Coleoptera, Curculionidae: Scolytinae), Zootaxa 4722 (6), pp. 540-554 : 550

Tricosa metacuneola (Eggers) comb. n.

( Figs 35–38 )

Xyleborus metacuneolus Eggers, 1940: 150 .

Xyleborus kaimochii Nobuchi, 1981: 143 . Synonymy: Smith et al., 2018: 397.

Diagnosis: 2.40–2.50 mm long (mean = 2.46 mm; n = 5); 2.67–2.78 times as long as wide. This species is distinguished by elytral discal striae and interstriae clearly uniseriate punctate, anterior margin of pronotum with a row of serrations, and protibia obliquely triangular.

Material examined: Paratype Xyleborus metacuneolus , [ INDONESIA] : Java, Buitenzorg , 15.x.1923 ( NMNH, 1). [ INDONESIA] : Java, Boger [sic] viii.1964, N.L.H. Krauss ( NMNH, 4) . MALAYSIA: Sabah, Sipitang, Mendolong , 19.iv.1988, S. Adebratt ( RABC, 1) . PAPUA NEW GUINEA: Madang, Ohu, J. Hulcr, ex Gymnacranthera paniculata ( MSUC, 1) . SINGAPORE: Bukit Timah , 50m, 25‒27.x.1998, B. H. Jordal ( RABC, 2) .

Distribution: Brunei, Indonesia (Java, Sulawesi), Japan, East & West Malaysia, New Guinea, Philippines, Singapore, Sri Lanka, Taiwan, Thailand.

Host plants: Probably polyphagous. Recorded from Buchanania , Mangifera (Anacardiaceae) , Swietenia (Meliaceae) , Castanopsis (Fagaceae) ( Nobuchi 1981; Beaver & Liu 2010) and Gymnacranthera (Myrsticaceae) .

Remarks: The paratype from Indonesia (Java; NMNH) and two specimens from Singapore and Malaysia (Sabah; RABC) were all found to have different pronotal length/width ratios of 1.08, 1.23 and 0.88 respectively. It is unclear whether the species is morphologically variable or if this species may be a species complex. At the time of this study DNA data was only available for T. metacuneola s.s. Future research is necessary to determine species limits.

Figures

FIGURES 19–38. Lateral, dorsal, posterior oblique and anterior view of Tricosa cattienensis (19–22), T. indochinensis (23–26), T. jacula (27–30), T. mangoense (31–34), T. metacuneola (35–38).