Shelter, ecophysiology and conservation status of Plectostylus araucanus (Pulmonata: Bothriembryontidae) in the fragmented Maulino Forest, central Chile

Abstract

Terrestrial mollusks are one of the least studied groups of terrestrial invertebrates, especially in the Neotropics. In Chile, there is scarce biological and ecological information about many genera, even though the group is quite diverse and occupies different habitats along the country. Plectostylus araucanus is the most recently described species and one of the few arboreal species found only in the coastal native forest of central-south of Chile. In this study, we recorded a new locality for P. araucanus in the Maule region and described ecological and physiological characteristics. The new locality is placed 204 km northwards of the type locality. Based on different records, Plectostylus araucanus is proposed as an endangered (EN) species under the distribution criterion of IUCN. Most of the specimens of P. araucanus were found living in tree cavities and away from the edge of native forest fragments. Physiological measures showed monthly differences, especially between some months of summer and fall and between months of the same season (i.e., summer). We discuss the implications of our results in the microhabitat selection, thermoregulation and habitat use by this tree snail, and the importance of this data in management and conservation for other native malacofauna.

The effect of landscape on functional connectivity and shell shape in the land snailHumboldtiana durangoensis

“…Based on these findings, we hypothesized that the functional connectivity of H. durangoensis on different temporal scales has been promoted by the presence of both temperate and cold temperate forests and that two patterns can be distinguished as has been suggested in Helix aspersa and Cepaea nemoralis (Arnaud, 2003;Schweiger, Frenzel & Durka, 2004;Barahona-Segovia et al, 2019). The first is a model of isolation by distance on a larger geographic scale (Pfenninger & Posada, 2002;Arnaud, 2003;Schweiger, Frenzel & Durka, 2004), and the second is possible dynamic metapopulation promoted both by environmental and landscape heterogeneity on a fine geographic scale, as has been documented for other land snails (Arnaud et al, 2001;Baur & Baur, 2013).…”

Forestry clear‐cuts increase environmental temperatures, affecting the ecophysiological responses of specialized beetles in fragmented landscapes

“…We took non‐invasive measurements of C . chilensis body temperature on the widest part of elytra, since this is the location of muscles used for movement, using an infrared thermometer with a precision of ±0.1°C (EXTECH Instruments, model 42,509, range: −20 to 510°C) This technique has been used with other invertebrates such as ladybirds (Barahona‐Segovia et al., 2016), land snails (Barahona‐Segovia, Riveros‐Díaz, et al., 2019) and spiders (Taucare‐Ríos et al., 2017; Veloso et al., 2012). Measurement was continued until the temperature of the infrared thermometer stabilized.…”

“…The most common thermoregulatory strategy used by ectotherms to maintain their bodies at optimal body temperature (defined as the environmental temperature where maximum performance is obtained; henceforth T opt ) for performance is searching for shelters that provide more appropriate thermal conditions (Angilletta, 2009;Barahona-Segovia, Riveros-Díaz, et al, 2019;Scheffers et al, 2014). Microhabitats such as ferns, leaf litter and ground vegetation can reduce mean air temperature by 1-2°C and reduce the time of organism exposure to extreme temperatures and thus decrease the vulnerability of ectotherm communities up to 32-fold (Scheffers et al, 2014).…”

Peer Review #2 of "The effect of landscape on functional connectivity and shell shape in the land snail Humboldtiana durangoensis (v0.2)"

“…durangoensis on different temporal scales has been promoted by the presence of both temperate and cold temperate forests and that two patterns can be distinguished as has been suggested in Helix aspersa and Cepaea nemoralis (Arnaud et al 2003;Schweiger et al 2004;Barahona-Segovia et al 2019), for which two patterns can be distinguished.…”