A Second, Cryptic Species of the Soft Coral Genus Incrustatus (Anthozoa: Octocorallia: Clavulariidae) From Tierra del Fuego, Argentina, Revealed by DNA Barcoding

The encrusting soft coral Incrustatus comauensis is a common denizen of hard substrates in the shallow sub-tidal zone from the central Chilean fjords to the Cape Horn region of southern South America. DNA barcoding of specimens collected from the Beagle Channel, Tierra del Fuego, Argentina, revealed the presence of a second, cryptic species of Incrustatus that is syntopic with I. comauensis. We describe Incrustatus niarchosi, a new species that can be distinguished morphologically from I. comauensis by differences in the microscopic ornamentation of the coenenchymal sclerites. To date, I. niarchosi n. sp. is known only from the Beagle Channel. A population of I. comauensis discovered in the intertidal zone in eastern Tierra del Fuego represents a new record of the species for that habitat and geographic region. Although the intertidal population is also distinct genetically, it is morphologically indistinguishable from sub-tidal Chilean populations of I. comauensis, and at present, there is insufficient evidence to support its status as a separate species

Unforeseen importance of historical collections as baselines to determine biotic change of coral reefs: the Saba Bank case

Botanical and zoological collections may serve as archives for historical ecological research on the effects of global change and human impact on coral reef biota. Museum collections may harbour old specimens of reef-dwelling species that have become locally extinct. Such collections also help to determine whether early records of invasive species can be obtained from times when they were not yet recognized as such. A case study (2006) involving Saba Bank, Caribbean Netherlands (former Netherlands Antilles), suggests that the coral reef fauna here may have become impoverished when compared with data obtained during an earlier expedition in 1972. However, the 1972 sampling may have been incomplete, as it was performed by professional divers who were not trained taxonomists, whereas the collecting in 2006 was done by experienced marine biologists who knew the taxa they were sampling. As Saba Bank has been under stress due to the anchoring of large vessels, and invasive species have been a potential threat as well, future studies are needed to obtain more insights into the changing reef biota of Saba Bank. Using this Saba Bank example, we want to address the importance of natural history collections as reservoirs of valuable data relevant to coral reef biodiversity studies in a time of global change. As such, these collections are still underexplored and underexploited

The magnitude of global marine species diversity

Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered. Results: There are similar to 226,000 eukaryotic marine species described. More species were described in the past decade (similar to 20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are similar to 170,000 synonyms, that 58,000-72,000 species are collected but not yet described, and that 482,000-741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7-1.0 million marine species. Past rates of description of new species indicate there may be 0.5 +/- 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science. Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century