100 years on: a re-evaluation of the first discovery of microfauna from Ross Island, Antarctica

Abstract

Over a century ago microfaunal diversity was first recorded by James Murray in lakes at Cape Royds, Ross Island, Antarctica. The report stands as the seminal study for today’s biodiversity investigations, and as a baseline to evaluate changes in faunal communities and introductions. In the present study, Cape Royds lakes were revisited and the mitochondrial c oxidase subunit I (COI) gene and morphology were used to compare diversity of Rotifera, Tardigrada and Nematoda with the records Murray published in the early 1900s. Cyanobacterial mats and the water column were sampled for microfauna from the five largest lakes using methods described by Murray. Across all five lakes similar patterns were observed for species distribution of all three phyla reported by Murray over 100 years ago. Some changes in species assemblages were identified within and between lakes, but there were no new introductions of named species for the Cape Royds region. Some of the species included by Murray in his monograph have been recently redescribed as Antarctic endemics, but others still retain their original name from the Northern Hemisphere holotypes and are also in need of revision to adequately determine the true endemism for these faunal groups.

From the Heroic Age to today: What diatoms from Shackleton's Nimrod expedition can tell us about the ecological trajectory of Antarctic ponds

“…Consistent with recent studies that have also made use of historical material to assess change in the McMurdo Sound Region (Jungblut and Hawes 2017;Jungblut et al 2018;Velasco-Castrill on et al 2018), our work suggests that the regional diatom metacommunity has remained essentially stable over the last century. Our inability to detect evidence of exotic or extirpated diatom species in one of Continental Antarctica's most accessed areas is a bit of good news among myriad reports on ecological collapse and biological invasions.…”

A hole in the nematosphere: tardigrades and rotifers dominate the cryoconite hole environment, whereas nematodes are missing

“…However, historically, these biogeographical surveys have been limited to macroorganisms. The emergence of new optical and molecular tools now allows the pursuit of similar questions for microorganisms, including single‐cell microbes and multicellular micrometazoans (Nkem et al ., 2006 a , 2006 b ; Guil, Sánchez‐Moreno & Machordom, 2009; Velasco‐Castrillón, Gibson & Stevens, 2014; Darcy et al ., 2018; Velasco‐Castrillón, Hawes & Stevens, 2018; Zawierucha et al ., 2018 b ). Recent studies show that the distributions of micrometazoan taxa can be related to physiological and dispersal constraints (Nkem et al ., 2006 a , 2006 b ; Dial et al ., 2012; Shain et al ., 2016; Zawierucha et al ., 2018 b ; Zawierucha et al ., 2019 b ), competition (Shaw et al ., 2018), geographical barriers (Jørgensen, Møbjerg & Kristensen, 2007; Czechowski et al ., 2016) and to ongoing shifts in environmental conditions (Andriuzzi et al ., 2018).…”

The need for increased protection of Antarctica's inland waters

“…This context is consistent with observations in terrestrial systems of non-native taxa, most frequently in the rapidly changing and heavily visited Antarctic Peninsula region (Greenslade et al 2012, Hughes et al 2015, 2020). In contrast, attempts to identify the presence of exotic taxa in the more extreme continental inland waters by comparing recent and museum-preserved samples from the heroic era of exploration are yet to discover any such taxa (Jungblut & Hawes 2017, Velasco-Castrillón et al 2018, Kohler et al 2021).…”