New species and sympatric relations of the
chigger mite species group talmiensis
(Trombiculidae, Neotrombicula)
A.A.
Stekolnikov
Parazitologiya, 35(6):
496-518 (2001) (In Russian, English summary).
S U M M A R Y
A revision of chigger mite species being
closely related to Neotrombicula talmiensis
(Schluger, 1955) has been performed. Two new species are described:
N. pontica sp. n. from Krasnodar
Territory (Western Caucasus) and N. sympatrica sp.
n. from Krasnodar Krai, Daghestan, Tuva, Armenia, Kyrgyzstan, and
Turkey (Rize Province).
N. pontica sp. n. is closely
related to N. carpathica Schluger et Vysotzkaya,
1970 and differs from this species by the larger number of idiosomal
setae (NDV = 75—99 vs. 63—77), shorter legs (lp = 782—847 vs. 844—920,
TaIII = 67—74 vs. 70—80), lesser m-t (0.180 vs. 0.192), slightly lesser
scutum and slightly longer setae.
N. sympatrica sp. n. is closely
related to N. carpathica and differs from this
species by the longer scutal and idiosomal setae (PL = 67—78 vs. 57—69,
H = 65—75 vs. 57—68, Dmin = 43—52 vs. 39—48, Dmax = 61—70 vs. 54—64),
longer legs (lp = 892—973 vs. 844—920, TaIII = 77—86 vs. 70—80) and
lesser m-t (0.168 vs. 0.192).
N. carpathica is reported for the
first time from Northern Caucasus (Karachai-Cherkess Republic,
Kabardino-Balkaria, North Ossetia);
N. taimiensis is reported for the
first time from Khakasia.
Data on joint occurrence of 3 species are
reported. The 3 types of sympatric pairs of the species have been found
in the Western Caucasus: 1)
N. pontica sp. n. and
N. sympatrica sp. n., 2) N. sympatrica
sp. n., and
N. carpathica, 3) N.
pontica sp. n., and N. carpathica.
Differences between species in those localities, where the joint
occurrence was recorded, have been analysed. Sympatric relations
between
N. sympatrica sp. n. and
N. carpathica are characterized by increased value of some
general diagnostic characters of these species, such as the length of
idiosomal setae and length of legs. In different sympatric localities,
different characters play main
distinguishing role. Besides that,
some local features appear in certain species of sympatric pairs
(narrow scutum in 3 samples of
N. carpathica, numerous idiosomal
setae in 1 sample of N. sympatrica), which differ
the populations of the sympatric pair, and also discriminate such
aberrant group from other material of the same species.
Functions produced by the method of
discriminant analysis are proposed for the purpose of diagnostics in
talmiensis group. Tests for
assumptions of discriminant analysis, such as normality and homogeneity
of variances, have been performed beforehand. Verifications of the
functions on test samples demonstrated the good quality of its working.
Key to species using discriminant functions has been constructed.
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