The first record of the cosmopolitan slug Deroceras laeve (O. F. Müller, 1774) (Gastropoda: Pulmonata: Agriolimacidae) in Bhutan

Abstract

The cosmopolitan slug Deroceras laeve (O. F. Müller) is reported from Bhutan for the first time, with the identity at one site confirmed through dissection. Here it was a minor pest of cabbage on a single farm at 2,780 m a.s.l. in north-western Bhutan. Two further, anatomically unconfirmed, records suggest that it is widespread in Bhutan. This, together with evidence that it is already widely distributed in nearby countries, suggests that it might have been in Bhutan for some time. Surveys are required to confirm its distribution and pest status in Bhutan, but current indications are that it is a very localised and occasional pest that can be readily managed through manual removal.

First record of an agriolimacid slug in Southeast Asia – Deroceras laeve (O. F. Müller, 1774) (Gastropoda: Pulmonata) recently introduced to the Socialist Republic of Vietnam

“…However, it is more difficult with D. laeve to delineate between its natural and introduced ranges. With a supposedly Holarctic natural distribution range (though there is dispute about whether it is native to North America, for example Wiktor (2000), Wiktor and Auffenberg (2002), Welter-Schultes (2012), Gittenberger et al (2018)), stretching from the arctic Tundra (Berman et al 2011) to the subtropics, D. laeve has by far the largest natural range amongst species of Agriolimacidae (Wiktor 2000). This goes along with an enormous ecological plasticity: it requires some dampness, but can tolerate freezing well below -20 °C, and the short life cycle allows it to grow and reproduce even in extremely short seasons of suitable conditions (Wiktor 2000, Berman et al 2011.…”

“…This goes along with an enormous ecological plasticity: it requires some dampness, but can tolerate freezing well below -20 °C, and the short life cycle allows it to grow and reproduce even in extremely short seasons of suitable conditions (Wiktor 2000, Berman et al 2011. Deroceras laeve occurs from sea level to 4800 m and in a variety of forests, wetlands, natural and agricultural habitats (Wiktor 2000, Gittenberger et al 2018. It is also a frequent pest in greenhouses (Rowson et al 2014).…”

“…and include natural as well as synanthropic habitats (Wiktor 2000). In addition populations along the southern foothills of the Himalayas have been considered as native: several localities in northern Pakistan (Wiktor andAuffenberg 2002, Hlavàč 2004), Nepal (districts of Kathmandu, Taplejung and Panchthar: Bössneck 2006, Budha et al 2015 and Bhutan (Gaza district in the NW, and further indications from two districts in central and southeastern Bhutan: Gittenberger et al 2018).…”