Choanoflagellates are single-celled aquatic flagellates with a unique morphology consisting of a cell with a single flagellum surrounded by a ''collar'' of microvilli. They have long interested evolutionary biologists because of their striking resemblance to the collared cells (choanocytes) of sponges. Molecular phylogeny has confirmed a close relationship between choanoflagellates and Metazoa, and the first choanoflagellate genome sequence has recently been published. However, molecular phylogenetic studies within choanoflagellates are still extremely limited. Thus, little is known about choanoflagellate evolution or the exact nature of the relationship between choanoflagellates and Metazoa. We have sequenced four genes from a broad sampling of the morphological diversity of choanoflagellates including most species currently available in culture. Phylogenetic analyses of these sequences, alone and in combination, reject much of the traditional taxonomy of the group. The molecular data also strongly support choanoflagellate monophyly rejecting proposals that Metazoa were derived from a true choanoflagellate ancestor. Mapping of a complementary matrix of morphological and ecological traits onto the phylogeny allows a reinterpretation of choanoflagellate character evolution and predicts the nature of their last common ancestor.evolution ͉ morphology ͉ holozoa ͉ animals ͉ protists

Human activities are threatening Borneo's unique biodiversity, but little is known on the status of freshwater invertebrates. We assessed changes in diversity and distribution of freshwater mussels (Bivalvia: Unionida) in northern Borneo, and identified drivers of present distribution and threats. Past distribution data were collected from literature and museum resources. Present distribution data were collected from 21 river basins, and 47 water quality, climatic, landscape and human variables explored as potential predictors of species presence/ absence. Species delimitations were identified by morphology and COI barcoding, and haplotype networks generated. Our data indicate that over the past 50 years, four of originally five native species have become very rare or possibly locally extirpated. Since these four species are endemic to Borneo, other Bornean river basins should urgently be surveyed to identify any remaining populations. In the same time span, the non-native Sinanodonta woodiana has become the most widespread freshwater mussel in northern Borneo. The fifth native species was identified as Rectidens sumatrensis and found in four Sarawakian river basins, thus contradicting previous assumptions of an endemic Bornean Rectidens species. Although a number of stable R. sumatrensis populations are retained across Sarawak, the species' strong spatial contraction in mainland Sundaland and apparent low tolerance to eutrophication suggest that it is vulnerable to further habitat alteration. Our results indicate that Borneo's (endemic) freshwater invertebrate biodiversity is declining rapidly. Comprehensive surveys targeting an array of invertebrate and vertebrate taxa are needed to identify Borneo's freshwater biodiversity hotspots, where conservation efforts should be concentrated.

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Ex situ conservation of Malaysian Mahseer (Tor tambroides and T. douronensis), the ecologically threatened freshwater fish species in Malaysia via semen cryo-banking was started in 2008 with the mature Tor species from four different locations in Peninsular Malaysia. At current stage, a total of 150 ml semen sample was collected from male fish of 73 T. tambroides and 15 T. douronensis and kept cryo-storage in liquid nitrogen (LN 2 ) in the semen cryo-bank at Freshwater Fisheries Research Centre (FFRC). Sperm motility after cryo-preservation was found to be reduced by an average of 15 and 30% for T. douronensis and T. tambroides respectively; i.e. with prefrozen motility 87.8 ± 7.9% (n = 73) and 88.8 ± 6.7% (n = 15), and post-thaw motility 54.9 ± 14.3% (n = 73) and 74.0 ± 11.2% (n = 15) for T. tambroides and T. douronensis respectively. The mean fertilization and hatching rates by using cryo-preserved semen in T. tambroides were 36.4 ± 10.5% (n = 360) and 34.5 ± 11% (n = 360) respectively; whereas were 89.8 ± 10.2% (n = 360) and 80.2 ± 16.6% (n = 360) respectively for fresh semen. Meanwhile, the survival rate of fry produced from cryo-preserved sperm (97.6 ± 3.1%, n = 360) was equally good (P > 0.05) when compared to the use of fresh sperm (99.7 ± 0.5%, n = 360). Sperm motility (%) during milt collection, before freezing and after thawing of each cryo-preserved semen samples was recorded. These tests were done with sperm from all semen samples and kept up to date into the Fishery Information Network System (INFOFins). The subsequent fertilization capacity and hatching rates of eggs fertilized with sperm from selected cryo-preserved semen sample were also quantified and recorded into INFOFins. Future prospects of the semen cryo-banking of Malaysian Mahseer is also reported and discussed in the present paper.