Acestrorhynchus is the sole genus of the family Acestrorhynchidae which includes 14 species currently recognized as valid. Species of Acestrorhynchus comprise small-to-medium sized piscivorous fishes and have been traditionally grouped on the basis of well-defined color patterns. A recent phylogeny, based on morphological characters, could not resolve the phylogenetic affinities of A. heterolepis and the relationships among the species of the clade formed by A. abbreviatus, A. altus, A. falcatus, A. lacustris, and A. pantaneiro. The simultaneous analysis of two mitochondrial genes (16S and ATP synthase subunits 6 and 8) and one nuclear intron (S7) was able to resolve the latter clade, but the position of A. heterolepis remained unresolved. The combination of the molecular and morphological data sets in a total evidence analysis resulted in a well-resolved hypothesis regarding the phylogenetic relationships of Acestrorhynchus species.
"To resolve these issues it will be necessary to investigate this group with expanded species sampling and combining molecular and morphological datasets, an approach that has been successful in similar cases (e.g. Gatesy et al., 2003; Mattern and McLennan, 2004; Pretti et al., 2009). "
[Show abstract][Hide abstract] ABSTRACT: A phylogenetic analysis is provided for representatives of more than one hundred species of the catfish family Loricariidae, including nearly all genera of the subfamilies Neoplecostominae and Hypoptopomatinae. This analysis is based on fragments of the subunit 1 of the cytochrome c oxidase gene (COI), the recombination activating genes 1 (RAG1) and 2 (RAG2), and the F-Reticulon 4 gene. We obtained an alignment of 4678 contiguous nucleotides for 136 species of 50 loricariid genera from five loricariid subfamilies, and ten outgroup species from five loricarioid families. Our results from Maximum Parsimony, Maximum Likelihood, and Bayesian analyses show the following set of interrelationships ((((Hypoptopomatinae, Neoplecostominae) Hypostominae), Loricariinae) Delturinae). However, neither Hypoptopomatinae nor Neoplecostominae were recovered as monophyletic groups. A previously hypothesized monophyly of Hypoptopomatini and Otothyrini was refuted. Furthermore, the genera Pareiorhaphis, Pareiorhina, Hisonotus and Parotocinclus were recovered as polyphyletic.
"Similarly, more and more taxonomists have used both morphological and molecular characters in their phylogenetic analyses (e.g. Teletchea et al. 2006; Knudsen et al. 2007; Pretti et al. 2009; Turan et al. 2009). Concerning more specifically the perceived inherent limits of the current Linnaean morphology-based system, see notably the specific responses of Lipscomb et al. (2003), Mallet and Willmott (2003), and Seberg et al. (2003) in Table I. "
[Show abstract][Hide abstract] ABSTRACT: In 2003, two different approaches-DNA taxonomy and DNA barcoding-were simultaneously proposed to overcome some of the perceived intrinsic weaknesses of the traditional morphology-based taxonomical system, and to help non-taxonomists to resolve their crucial need for accurate and rapid species identification tools. After 7 years, it seems unlikely that a completely new taxonomical system based on molecular characters only (DNA taxonomy) will develop in the future. It is more likely that both morphological and molecular data will be simultaneously analyzed, developing what has been coined as "integrative taxonomy". Concerning DNA barcoding, it is now clear that it does not focus on building a tree-of-life nor to perform DNA taxonomy, but rather to produce a universal molecular identification key based on strong taxonomic knowledge that is collated in the barcode reference library. The indisputable success of the DNA barcoding project is chiefly due to the fact that DNA barcoding standards considerably enhance current practices in the molecular identification field, and standardization offers virtually endless applications for various users.
Mitochondrial DNA 12/2010; 21(6):206-26. DOI:10.3109/19401736.2010.532212 · 1.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We describe our work on automatic transcription of radio and
television news broadcasts. This problem is very challenging for large
vocabulary speech recognition because of the frequent and unpredictable
changes that occur in speaker, speaking style, topic, channel, and
background conditions. Faced with such a problem, there is a strong
tendency to try to carve the input into separable classes and deal with
each one independently. In our early work on this problem, however, we
are finding that the rewards for condition-specific techniques are
disappointingly small. This is forcing us to look for general, robust,
and adaptive algorithms for dealing with extremely variable data. We
describe the BBN BYB-LOS recognition system configured to handle
off-line transcription and we characterize the speech contained in the
1996 DARPA Hub-4 testbed. On the partitioned development test set, we
achieved a 29.4% overall word error rate
Acoustics, Speech, and Signal Processing, 1997. ICASSP-97., 1997 IEEE International Conference on; 05/1997
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