Material and methods
Measurements were taken as straight lines (to the nearest
0.1 mm) between two points (see Schindler & Schmidt
2006) with an electronic digital calliper. Proportions
are expressed as percentages of standard length (SL).
Terminology for measurements and colour pattern is
based on Witte & Schmidt (1992) with modifications as
specified in Schindler & Schmidt (2006). Counts were
made as described by Witte & Schmidt (1992) except
for the number of predorsal scales, which were counted
continuously. Numbers in brackets indicate the number
of specimens examined for the datum in question.
To ensure the optimally objective comparison of colours,
all photographs of live specimens were taken under
the same conditions. The photographs were taken using
a camera flash with a colour temperature of about
5600 Kelvin, without any influence from any other light
source.
Water parameters were measured in the field with the
following instruments: wtw-Weilheim, type pH 320 with
pH electrode SenTix 21 for the hydrogen-ion concentration
and water temperature, and Sera Handmessgerät
(tolerance of 0.2%) for the electrical conductivity.
The material examined is listed under the species description
below. Types are deposited in the Senckenberg
Naturhistorische Sammlungen Dresden, Museum für
Tierkunde, Dresden (MTD). Specimens not indicated as
the holotype or paratypes are non-type material. The description
follows the general format used by Tan & Ng
(2005). In addition to the data obtained from material
examined, data from Tan & Ng (2005; 2006), Witte &
Schmidt (1992), and previously published descriptions of
species (see introduction) were also used.
In accordance with previous taxonomic publications
on the genus Betta (see Tan & Ng, 2005; 2006), the new
species is diagnosed and described on eidonomical features.
The definition of species groups and the classification
of species follows Tan & Ng (2005). The species
concept used is the diagnostic variant of the ‘phylogenetic
species concept’ (Nixon & Wheeler, 1990).