Confirming the presence of a fourth species of non-native house gecko of the genus Hemidactylus Oken, 1817 (Squamata, Gekkonidae) in Colombia

The Indo-Pacific Gecko, Hemidactylus garnotii Duméril &amp; Bibron, 1836, is a species of house gecko native to Southeast Asia and Pacific Islands. As with many of its congeners, this gecko species has been accidentally introduced to other parts of the world. In January 2018, several photographs of “H. frenatus” from Colombia posted in iNaturalist.org, were noticed to have some morphological features related to H. garnotii. This discrepancy led us to inspect museum specimens and to confirm the presence of H. garnotii for more than a decade in Colombia.</jats:p

Data for: Shifts in thermal preference of introduced Asian House Geckos (Hemidactylus frenatus) in temperate regions of southeastern Australia

This is a dataset of thermal preference of H. frenatus from Thailand and Australia. The data consist of hourly body temperatures of the geckos in cost-free thermal gradients

New Records of Lepidodactylus lugubris (Duméril and Bibron, 1836) (Squamata, Gekkonidae) from Thailand and a Brief Revision of Its Clonal Composition in Southeast Asia

The mourning gecko Lepidodactylus lugubris broadly occurs in the Indo-Pacific region and is also recorded from some parts of the insular and coastal Latin America. Despite its presence in a number of localities along coastal Southeast Asia, L. lugubris has not ever been reported from Thailand. We observed several individuals of this gecko on Bulon Le Island in 2012 and 2013, and on this island and Mook Island in 2017. This is the first record of L. lugubris in Thailand. In addition, we examined photographs of this species taken in Southeast Asia and deposited in iNaturalist.org (including ours from this study), and recognized two clones on the basis of dorsal color pattern: triploid clone C from Thailand, India (Andaman Islands), Indonesia, and Malaysia, and diploid clone A from Singapore

Plasticity in thermal hardening of the invasive Asian house gecko

The Asian house gecko (Hemidactylus frenatus) is a tropical invasive species that has established and spread throughout several temperate regions around the world. In some invasive species, rapid thermal acclimation (thermal hardening) may contribute to their success in occupying a wide range of climates. In this study, we investigated whether invasive house geckos from southeastern Australia show differing thermal hardening responses than individuals from the native range in Thailand. In the laboratory, we measured the basal heat tolerance (CTmax) of the geckos and their heat hardening response after being subjected to the second thermal stress after 1, 3, 5, 7, 9, or 11 h. When geckos had recovered, we measured their basal cold tolerance (CTmin) and cold hardening response over the same time intervals. We then explored whether hardening responses differed between populations or among time intervals. We found that basal heat tolerances did not differ between populations, but geckos from Australia had lower cold tolerance than geckos from Thailand. The magnitude of the heat hardening was similar between populations, but the introduced geckos had a higher magnitude of cold hardening. The native geckos could maximize their cold tolerance capacity for only 0.6 °C, versus 0.9 °C for the introduced geckos. Also, geckos from Australia exhibited faster responses to thermal stress than did geckos from Thailand. Maximum thermal tolerances as a result of hardening responses peaked within three hours after thermal stress in Australian geckos (adjusted means = 44.0 °C for CTmax and 9.9 °C for CTmin) and at five hours after thermal stress in Thailand geckos (adjusted means = 44.2 °C and 10.2 °C, respectively). The plasticity in the thermal hardening of the invasive gecko should enable it to survive rapid temperature fluctuations, especially winter cold snaps that occur in temperate regions

Shifts in thermal tolerance of the invasive Asian house gecko (Hemidactylus frenatus) across native and introduced ranges

The ability to rapidly adjust thermal tolerance in response to variable temperatures may facilitate the success of invasive species in non-native ranges. The Asian house gecko Hemidactylus frenatus is native to the tropics of South and Southeast Asia. This small lizard has spread across the globe and has also successfully invaded colder regions of Australia. In this study, we investigated whether this species displays plasticity in thermal tolerance in its introduced range. We measured cold tolerance (CTmin) and heat tolerance (CTmax) of H. frenatus from two native tropical populations in Thailand, and two introduced subtropical populations in southeastern Australia. We also explored seasonal variation in the thermal tolerance of the introduced populations. We found that heat tolerance (CTmax) of geckos did not differ among four populations in Thailand and Australia (range = 43.4–43.7 °C). By contrast, geckos from southeastern Australia had lower cold tolerance (CTmin) (mean = 10.43 °C) than geckos from Thailand (mean = 11.57 °C). We also documented seasonal shifts in cold tolerance of H. frenatus from southeastern Australia. Geckos captured in winter had cold tolerances 1–2 °C lower than those captured in summer. Unexpectedly, this shift in cold tolerance was accompanied by a 1–2 °C upward shift in heat tolerance. Our results support a growing body of evidence showing that tropical invaders can adjust cold tolerance downwards via plasticity or acclimation. Such changes may allow tropical invaders to expand their geographic range into colder regions of non-native ranges

Data for: Shifts in thermal preference of introduced Asian House Geckos (Hemidactylus frenatus) in temperate regions of southeastern Australia

This is a dataset of thermal preference of H. frenatus from Thailand and Australia. The data consist of hourly body temperatures of the geckos in cost-free thermal gradients

Shifts in thermal preference of introduced Asian house geckos (Hemidactylus frenatus) in temperate regions of southeastern Australia.

Despite its tropical origin, the Asian house gecko (Hemidactylus frenatus) is currently invading higher latitudes around the world. In this study, we investigated whether the introduced geckos in the subtropical/temperate region of southeastern Australia have shifted their thermal biology to cope with colder temperatures. In the lab, we measured the body temperatures of geckos from Thailand and Australia in a cost-free thermal gradient. Native H. frenatus from Thailand displayed a diel pattern of thermoregulation. Geckos maintained higher body temperatures during mid-afternoon and at dusk but selected cooler temperatures during the night. Introduced geckos showed a similar pattern of thermoregulation, but selected lower body temperatures in summer (mean = 28.9 °C) and winter (mean = 25.5 °C) than native geckos (mean = 31.5 °C). While the Asian house geckos from Thailand did not alter their body temperatures after feeding, their conspecifics from southeastern Australia selected body temperatures that were 1.6-3.1 °C higher after feeding. In conclusion, our study shows that invasive house geckos in Australia have shifted their preferred body temperatures downwards relative to their native conspecifics in Thailand, presumably as a result of plasticity or natural selection. Our findings suggest that these tropical geckos have adapted to colder regions, and thus, they may spread much further than expected for a tropical ectotherm

New method for arbuscular mycorrhizal fungus spore separation using a microfluidic device based on manual temporary flow diversion.

Arbuscular mycorrhizal fungi are beneficial components often included in biofertilizers. Studies of the biology and utilization of these fungi are key to their successful use in the biofertilizer industry. The acquisition of isolated spores is a required step in these studies; however, spore quality control and spore separation are bottlenecks. Filtered and centrifuged spores have to be hand-picked under a microscope. The conventional procedure is skill-demanding, labor-intensive, and time-consuming. Here, we developed a microfluidic device to aid manual separation of spores from a filtered and centrifuged suspension. The device is a single spore streamer equipped with a manual temporary flow diversion (MTFD) mechanism to select single spores. Users can press a switch to generate MTFD when the spore arrives at the selection site. The targeted spore flows in a stream to the collection chamber via temporary cross flow. Using the device, spore purity, the percentage of spore numbers against the total number of particles counted in the collecting chamber reached 96.62% (median, n = 10) which is greater than the spore purity obtained from the conventional method (88.89% (median, n = 10))

Effects of the Australian 2019–2020 megafires on a population of endangered broad‐headed snakes Hoplocephalus bungaroides

The 2019–2020 Australian megafires were unprecedented in their intensity and extent. These wildfires may have caused high mortality of adult broad-headed snakes Hoplocephalus bungaroides which shelter inside tree hollows during summer. We evaluated the impacts of two high-intensity wildfires (2002 Touga Fire and 2020 Morton Fire) on a broad-headed snake population in Morton National Park, south-eastern Australia. We analysed a 29-year mark–recapture data set to estimate survival rates of adults in years with and without wildfires, and with and without human disturbance to rock outcrops. To examine the short-term effects of fire on occupancy, we analysed presence–absence data collected from 25 sites during 2019 and 2020. Estimates of occupancy were higher for 2020 (0.93 ± 0.09) than for 2019 (0.66 ± 0.14), while detection rates were constant (0.40 ± 0.06). Over the period 1992–2020, the best supported Cormack–Jolly–Seber model was one in which adult survival rates were high and stable (0.81 ± 0.04), but were 23% lower in years when humans disturbed rocks (0.63 ± 0.08). A model in which adult mortality was 20% higher in years with human disturbance and 14% higher in years with wildfires was also supported. Estimates of abundance revealed that the population declined by 34% after the Touga Fire, and 26% after the Morton Fire. Over the 29-year study, the population has declined by 60%. Our results highlight how mortality events from wildfires need to be evaluated in the context of other threatening processes. For this population, the removal of snakes and associated habitat disturbance poses a more serious threat to population viability than infrequent wildfires