Some soil-inhabiting mites from Zanzibar (Acari: Laelapidae)
Author
Joharchi, Omid
Author
Halliday, Bruce
Author
Khaustov, Alexander A.
Author
Ermilov, Sergey G.
text
Zootaxa
2018
2018-11-06
4514
1
23
40
journal article
28113
10.11646/zootaxa.4514.1.2
94abe156-ba42-47c9-b3f4-584fa793e129
1175-5326
2605788
91884B4A-C16E-4DF2-8A1F-07383558180C
Gaeolaelaps praesternalis
(Willmann)
Hypoaspis praesternalis
Willmann, 1949
: 115
.
Hypoaspis praesternalis
.—
Evans, 1953
: 272
;
Ryke, 1963
: 2
;
Ma & Yin, 2011
: 119
;
Saito & Takaku, 2011
: 88
.
Hypoaspis
(
Hypoaspis
)
praesternalis
.—
Van Aswegen & Loots, 1970
: 190
.
Hypoaspis
(
Gaeolaelaps
)
praesternalis
.—
Evans & Till, 1966
: 173
.
Specimens examined
: Nine females,
Tanzania
,
Zanzibar
, forest litter,
06°16' S
,
039°25' E
,
8 m
.
a.s.l.,
2 February 2018
, coll. S.G. Ermilov, A.A. Khaustov (in TUMZ). One female,
Poland
, Roztoczanski National Park, Jarugi Reserve, beech forest,
27 September 1986
, D. Sell coll.; one female,
Poland
, Roztocze Region, Hrebenne, beech forest,
6 August 1986
, Błoszyk & Hałka coll.; one female,
Poland
, Roztocze Region, Kąty, xerophyllous grasses,
5 August 1986
, Błoszyk & Hałka coll. (in ANIC). One male,
Germany
, Zorbig, Anhalt-Bitterfeld, 1960, det Willmann (in Zoologische Staatssammlungen, München).
Notes.
Gaeolaelaps praesternalis
was described from meadow soil in
Poland
(
Willmann, 1949
). It has also been reported from
Tanzania
(
Evans, 1953
;
Van Aswegen & Loots, 1970
),
Germany
(
Karg, 1962
),
South Africa
(
Ryke, 1963
),
Great Britain
(
Evans & Till, 1966
),
Japan
(
Saito & Takaku, 2011
) and
China
(
Ma & Yin, 2011
). Our specimens agree very well with the description given by
Evans & Till (1966)
. The species is recognised by the presence of 39 pairs of simple setae on the dorsal shield, including two pairs of
Zx
setae; some setae in the opisthonotal region long enough to reach the base of the next posterior setae; peritreme short, extending to the midlevel of coxa II; a pair of granular pre-sternal plates; and tarsus IV with two very elongate setae
pd2
,
pd3
(88–98).
The literature reveals some confusion about the identity of this species. The original description of
Hypoaspis praesternalis
by
Willmann (1949)
is brief, and both the description and illustrations lack some important details. The description of
Hypoaspis nolli
Karg, 1962
is more detailed, but does not include a direct comparison with
H. praesternalis
.
Evans & Till (1966)
synonymised these two species, but did not provide any explanation for that decision, and did not give details of the specimens they examined.
Costa (1968)
examined specimens of both species from
Germany
provided by Karg, and distinguished them by the length of the peritreme and the ornamentation of the dorsal shield.
Karg (1971 and later papers)
separated
H. nolli
from
H. praesternalis
on the basis of the length of the peritreme, the length of the setae on the dorsal shield, total body size, and the shape of the spermatodactyl of the male.
Kavianpour
et al.
(2013)
and
Kavianpour & Nemati (2014)
also recognised these two species, but reported that
H. praesternalis
sensu Evans & Till
was actually a misidentification of
H. nolli
.
Ma (2006)
considered that
Gaeolaelaps postreticulatus
(
Xu & Liang, 1996
)
is a synonym of
G. praesternalis
, without providing any supporting evidence.
Ma & Yin (2011)
then reported that
G. praesternalis
is very abundant in grassland soil in
China
. However,
Xu & Liang (1996)
distinguished between
G. postreticulatus
and
G. praesternalis
by the length of some dorsal shield setae, the number of dorsal shield setae, the length of the peritreme, and the shape of the spermatodactyl. Some of these interpretations are questionable, because the statements by Xu & Liang are not always consistent with their own illustrations. If their illustration of the male chelicera is accurate, the spermatodactyl is straight, pointed at the tip, and its free section is 50% longer than the movable digit. In the chelicera of
G. praesternalis
illustrated by
Evans & Till (1966)
, the spermatodactyl is curved upward, has a large distal knob, and its free section is shorter than the movable digit.
Saito & Takaku (2011)
showed the spermatodactyl of
G. praesternalis
from
Japan
as extremely long, curved downward, and with a blunt tip.
Ma & Yin (2004)
also illustrated a very long spermatodactyl for this species, with a blunt tip that curves upward. We have examined a male of
G. praesternalis
identified by Willmann (from Zörbig,
Germany
, 1960, therefore not a
type
specimen). Its spermatodactyl is sharply bent upward, distally pointed, and its free section is much shorter than the movable digit.
Willmann (1949)
described the metasternal setae of the female of
G. praesternalis
as inserted on small triangular plates.
Ryke (1963)
and
Evans & Till (1966)
specifically stated that the metasternal plates are absent, and the metasternal setae are inserted in the soft integument. This evidence from both the males and females strongly suggests that different authors have used the name
G. praesternalis
to refer to several different species.
We have been unable to locate the
holotype
of
H. praesternalis
.
It is not present in the Willmann collection in the Zoologische Staatssammlungen, München (Stefan Friedrich, pers. comm.). Our identification of specimens from
Zanzibar
is supported by comparison with three females from
Poland
in ANIC (identified by Halliday).