systematics of chiggers of the minuta
group, genus Neotrombicula
250-266 (1995) (In Russian, English summary).
S U M M A R Y
Taxonomical analysis of minuta-group
in the genus Neotrombicula has been carried out.
Descriptions of 6 species has been corrected. The main corrections are
as follows. 1). In
fD=2H-(6—11)-(6—9)-(6—8)-4-... The common fD=2H-8-6-6-4-6-2. 2).
N. lubrica differs from
N. minuta first of all in the number of setae in the 4th
dorsal row and in the first rows of V, and also in more dense
punctation of scutum. 3).
N. irata has fD=2H-6-6-6-2-6-2
but not 2H-6-6-6-4-4-4 as in description. 4). Both
N. irata and N. lubrica
has SB anterior to PL, and in N. lubrica it is
more anterior than in
One new species, N. dimidiata
sp.n. is described from rodents collected in Western Kopetdagh
(Turkmenistan) and Northern Tadjikistan. The new species is similar to
N. minuta but differs in presence
of 2 setae in the 4th dorsal row vs. 4 in
N. minuta, lesser number of setae
in the anterior rows of V (8 vs. about 12 in
N. minuta), greater values of D
and V mean lengths (35—43 vs. 33—35, and 32—39 vs. 27—30 in
N. minuta, respectively), and by
greater Ip (847—982 vs. 786—877 in N.
minuta). The new species clearly differs from N.
lubrica in the shape of the scutum and in more sparse
punctation of it.
For N. scrupulosa an
analysis of geographical variability has been carried out. The methods
used had been previously devised for ticks (Filippova e.a., 1995).
Nonmetric multidimensional scaling on 8 characters (AW, SB, PSB, SD,
AP, AM, D[mean] and NDV) has been used to obtain the picture of
relative distances between samples. Almost all measurable characters,
fD and NDV in the species show a significant variability, but
intervals of their values for different populations are overlapped.
Comparing the diagram showing relative distances between samples from
different localities (Fig. 4) and the picture of their disposition on
the map (Fig. 5), one can conclude that it is a case of a cline,
stretching approximately in the latitudinal direction.
For N. corvi,
N. lucida, N. scrupulosa and
N. lubrica new hosts and/or new localities are pointed out.
The distribution of
N. minuta is probably restricted
in the Southern Ukraine. Steppes and similar biotopes in Caucasus,
Bashkiria, Northern, Eastern and Southern Kazakhstan, Altai Territory,
Tuva and Mongolia are inhabited by another species,
N. scrupulosa. In the mountains
of the Middle Asia minuta-group is represented by
several species appeared to be local.