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A New Species of Homalopteroides (Teleostei: Balitoridae) from Sarawak, Malaysian Borneo

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Homalopteroides avii, new species, is described from the Rajang River basin, Sarawak, Malaysian Borneo. It is distinguished from all other species of Homalopteroides by a wider gape of 28.5-33.3% HL vs. 22.3-24.2% for H. wassinkii, 20.0-28.4% for H. modestus, 19.1% for H. rupicola, 19.1-27.3% for H. smithi, 20.0-23.2% for H. stephensoni, 20.226.9% for H. weberi, 18.4-26.0% for H. tweediei, 17.3% for H. indochinensis, 17.4-21.2% for H. nebulosus, and 18.0-19.0% for H. yuwonoi It is further distinguished from species of Homalopteroides by the presence of a lateral cephalic stripe vs. absence in H. modestus, H. rupicala, H. smithi, H. tweediei, H. nebulosus, and H. yuwonoi; deeper caudal peduncle, 10.1-10.9% SL, vs. 8.4-9.0% for H. wassinkii, 8.7% for H. rupicola, 7.7-9.1% for H. smithi, 6.1-6.6% for H. stephensoni, 6.7-8.0% for H. weberi, 8.0-9.4% for H. tweediei, 9.3-9.8% for H. nebulosus, 8.7% for H. indochinensis, and 7.3% for H. yuwonoi; circumpeduncular scale count of 20-22 vs. 16 for H. rupicola, H. stephensoni, H. nebulosus, H. indochinensis, and H. yuwonoi, 14-16 for H. tweedei, and 16-18 for H. smithi and H. weberi; total pelvic-fin ray count of 9 vs. 10 for H. stephensoni, H. weberi, and H. yuwono. The species is relatively large for the genus, reaching 52.9 mm SL.
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... Measurements follow Hubbs and Lagler (2004) or Kottelat (1984); see Randall and Page (2012) for measurements from each source. Counts follow Randall and Page (2014), and terminology follows Randall and Page (2015). All measurements are given in millimetres (mm). ...
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... Data on fisheries diversity in the Sarawak area ( Figure 1), Malaysia, were extracted from published literatures (Regan, 1906;Watson, 1981;Mohsin & Ambak, 1996;Blaber et al., 1998;Doi et al., 2001;Rajali & Arshad, 2001;Motomura et al., 2002;Parenti & Lim, 2005;Yano et al., 2005;Atack, 2006;Rahim et al., 2009;Ambak, 2010;Chong et al., 2010;Hassan et al., 2010;White et al., 2010;Giam et al., 2012;Nyanti et al., 2012a;Nyanti et al., 2012b;Tan & Lim, 2013;Nyanti et al., 2014;Randall & Page, 2014;Froese & Pauly, 2017). In addition, the name of the species and location of detection was recorded and supplemented with other information extracted from Fishbase (Froese & Pauly, 2017) and Sealifebase (Palomares & Pauly, 2017). ...
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... Morphological. Measurements follow Hubbs & Lagler (2004) or Kottelat (1984) (see Randall & Page 2012 for measurements from each source), and counts follow Randall & Page (2014). The definition of a rostral cap follows Roberts (1982). ...
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