Search

Information on the ecology of invertebrate communities populating Macrocystis pyrifera forests in the Falkland Islands is scarce. Indeed, the factors influencing diversity, distribution and community structure have never been studied here. Benthic photoquadrats were collected along three permanent 20 m transects at three depth strata (shallow 5–10 m; middle 10–15 m; deep 15–20 m) off the coast of Kidney Island, Falkland Islands from Austral summer 2009 to Austral spring 2010. 146 taxa comprising 10 phyla and 21 classes were recorded during the surveys, with the most abundant sessile and vagile taxa being Spirorbinid worms and the hermit crab Pagurus comptus, respectively. Community structure was influenced by depth, with highest species richness in the middle depth stratum, and strong contrasts between the communities in the shallow and deep depth strata. Influence of season on community structure was evident, though not as strong a factor as depth. Spring and summer months were most species rich, demonstrating a difference between the shallow subtidal regions of Patagonia where species richness was reported to be highest in Austral autumn and winter. The effect of substrate and depth was also investigated for the abundance of individual taxa. This study provides the first description of the fauna and flora of shallow rocky reefs in the Falkland Islands, describing how these communities change over small spatial and temporal scales. The outcomes of this investigation contribute to better understanding ecological patterns of the Falklands shallow benthic environments and adds knowledge to the biogeography of the South Atlantic. [ABSTRACT FROM AUTHOR]

The Subantarctic brown alga Cladochroa chnoosporiformis had been collected only on one occasion by Carl Skottsberg in 1907 from Port Philomel, West Falkland, Falkland Islands, resulting in its formal taxonomic description. Due to the lack of reports since then, doubts remained about its existence and identity. Within the framework of this study, Cladochroa was rediscovered 106 years after its original description at its type locality, confirming its existence and the morphological features described by Skottsberg. The re-collection enabled molecular studies on field material and isolated cultures. Sequences of nrDNA, rbcL, and 5′-COI suggest that C. chnoosporiformis is conspecific with Utriculidium durvillei, which has nomenclatural priority. However, the morphologies of C. chnoosporiformis and U. durvillei are significantly different. Utriculidium may be the gametophyte generation of Cladochroa, or hitherto unknown factors cause highly different morphologies without alternating generations. [ABSTRACT FROM AUTHOR]