Calambus Thomson, 1859

Arimoto, Kôichi, 2020, First record and new species of the genus Calambus Thomson (Coleoptera Elateridae, Dendrometrinae) from Taiwan, Zootaxa 4853 (1), pp. 42-50 : 43-44

Genus Calambus Thomson, 1859

Calambus Thomson, 1859: 103 (original description; type species: Elater bipustulatus Linnaeus, 1767: 652 ; by monotypy).

Diagnosis. Frons without depression. Supra-antennal carina incomplete medially. Frontclypeal region gradually sloping to base of labrum. Antennae serrate from antennomere IV; antennomere II shortest. Pronotum without median longitudinal depression; subapical sublateral incision near hind angles present; median basal tubercle indistinct; hind angle without carina, with apex rounded. Hypomeron shining; punctures different in size. Anterior lobe of prosternum broadly rounded, exceeding anterior angles of prothorax. Sides of of prosternal spine straight in ventral view. Pronotosternal suture not grooved. Anterior margin of scutellar shield more or less rounded; side of scutellar shield emarginate anteriorly. Posterior margin of mesosternite between mesocoxae as wide as or wider than half width of mesocoxa. Elytral outmost interval narrowly extending sideways, forming flat plate; apices of elytra rounded.

Distribution. Palearctic realm ( Austria, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, France, Germany, Great Britain, Greece, Hungary, Ireland, Italy, Japan excluding the Ryukyu Islands, Latvia, Lithuania, Luxembourg, Montenegro, The Netherlands, Norway, Poland, Romania, Russia, Serbia, Slovakia, Spain, Switzerland, Sweden, Ukraine): six species ( Cate 2007). Oriental realm (mainland China, Taiwan): three species ( Schimmel and Tarnawski 2017; Prosvirov 2018). New record from Taiwan.

Bionomics. The members of the genus live in forests. Larvae of the two Japanese species, C. japonicas and C. mundulus , which are indistinguishable at the larval stage, are found under the bark of rotten wood, in cracks in the bark of living wood, under moss on tree bark, and among fallen leaves ( Ôhira 1962). They actively prey on small insects and spiders ( Ôhira and Inaizumi 1999). During the adult stage, the Japanese species were observed overwintering under peeling bark of Cinnamomum camphora (L.) J.Presl, Cryptomeria japonica (L.f.) D.Don, and Zelkova serrata (Thunb.) Makino , and in moss on the bark of Symplocos coreana (H.Lév.) Ohwi ( Shiraishi 1999, 2002). The adults frequently fly in the forest and have been collected by Malaise traps ( Ôhira and Inoue 1999); they have also been seen on the flowers of trees ( Shiraishi 1999) from spring to summer. Calambus kusuii , which is distributed from the Far East of Russia to Hokkaido, Japan, was also found under the bark of various deciduous and coniferous trees ( Prosvirov 2018).

There is no ecological information on the Taiwanese species, although I suspect that it probably has similar habits to its congeners.