Glaucalges tytonis sp. n. (Analgoidea, Xolalgidae) from the barn owl Tyto alba (Strigiformes, Tytonidae): compiling morphology with DNA barcode data for taxon descriptions in mites (Acari)
Author
Dabert, Jacek
Author
Ehrnsberger, Rainer
Author
Dabert, Miroslawa
text
Zootaxa
2008
1719
41
52
journal article
10.5281/zenodo.181058
128eccfe-2057-4f50-bd61-02f8eacfd8f0
1175-5326
181058
Glaucalges tytonis
sp. nov.
Material examined.
Type
material:
1 male
holotype
,
3 male
,
3 female
paratypes
from
Tyto alba
(
Strigiformes
,
Tytonidae
), near Osnabrueck (
52.16 N
0 8.03 E
),
Germany
,
12 November 1992
, no other data;
DNA
barcode GenBank Acc.
EU271955
for male
holotype
and
3 male
paratypes
, voucher
AMUFM
636; remaining
paratypes
vouchers
AMUFM
637–639.
Additional material:
17 males
from same host (another bird individual), same data;
DNA
barcode Gen- Bank Acc.
EU271956
for
13 males
, voucher
AMUFM
795; remaining individuals vouchers
AMUFM
791– 794.
Comparative material:
Glaucalges attenuatus
, two samples: (1)
9 males
from
Asio otus
(
type
host species), near Osnabrueck,
Germany
,
26 February 1993
, no other data;
DNA
barcode GenBank Acc.
EU271958
for
8 males
, voucher
AMUFM
780, (2)
3 males
,
2 females
from same host, Poznan (
52.25 N
16.52 E
),
Poland
,
11 May 2005
, coll. A. Badek;
DNA
barcode GenBank Acc.
EU271957
for all individuals, voucher
AMUFM
211.
Description.
Male
(
Figs 1
,
2
,
5
A–B, 6, 7). Gnathosoma with rectangular subcapitulum and finger-like appendages on lateral margins, length of gnathosoma 50 (48–54), width 48 (46–50), length/width 1.0 (1.0– 1.1). Idiosoma relatively stout, strongly narrowing terminally and shaped as inverted triangle, length 368 (320–375), width 243 (174–255), length/width 1.5 (1.5–1.8). Propodosoma and hysterosoma lengths 110 (96– 115) and 258 (224–260) respectively, propodosoma/hysterosoma 0.4. Terminal margin of opisthosoma with elongated trapezoidal opisthosomal lobes fused medially. Remnants of interlobar cleft are connected with posterior part of ovate supranal concavity in a keyhole-like structure. Length of the cleft including supranal concavity 80 (62–87), width at the level of setae
h2
bases 11 (9–14). Terminal margins of lobes with tongue-like rounded membranes separated by roundly triangular incision reaching anteriorly level of insertion of setae
h3
. Lateral opisthosoma with narrow membranes extending from bases of legs IV to level anterior to bases of setae
f2
. Pronotal shield triangular in shape anteriorly to level of setae
si
, posteriorly to this level rectangular; length of the shield 105 (97–112), maximal width 90 (82–90). Shield uniformly dotted, occupying medial part of dorsal propodosoma. Scapular shields well developed, shaped as quadrangles. Setae
se
shaped as macrosetae, set on striated tegument between humeral and pronotal shields. Setae
si
minute, set on lateral margins of pronotal shield. Humeral shields large, rounded with medium-sized setae
c2
at anterior margins. Hysteronotal shield well developed and covers most of dorsal surface of hysterosoma; anterior margin concave. Maximal width of the shield 115 (109–122). The shield uniformly dotted with two longitudinal furrows extending from the level posterior to cupules
im
to bases of setae
e2
. Dorsal setae
c1
,
d1
,
e1, h1
absent. Setae
ps1
longer than distance
d2–d2
. Lateral setae
d2
,
e2
,
f2
long;
d2
and
e2
extending beyond the level of tips of terminal membranes (
Fig. 4
A). Setae
h2
and
h3
shaped as macrosetae longer than idiosoma. All dorsal and lateral setae piliform. Openings of opisthonotal glands
gl
absent. Only cupules
im
visible, set posterior to bases of setae
d2
. Distances between setae:
c2–c2
171 (136–186),
c2–d2
62 (51–68),
d2–d2
107 (100–108),
d2–
e2
90 (89–102),
e2–
e2
78 (71–77),
h3–h3
37 (35–39),
ps1–ps1
20 (18–19).
FIGURE 1.
Glaucalges tytonis
sp. n.
, male. A – ventral view, B – dorsal view. Setal designations after Gaud and Atyeo (1996).
Epimerites I fused as Y with very short sternum (
Fig. 5
B). Coxal fields of ventral propodosoma and coxal fields III without sclerotized shields near epimerites. Coxal fields IV completely covered by well sclerotized shields with medial expansions encompassing bases of setae
3a
; in more weakly sclerotized individuals these expansions may be partly or completely reduced. Genito-anal region without cuticular shields with exception of minute square sclerite between setae
ps3
. Genital arch flat, length 11 (10–12), width 16 (14–15) with very short aedeagus. Genital acetabula set on epimerites IV laterally to genital organ. Setae
3b
shaped as long macrosetae reaching by tips bases of
f2.
Setae
ps2
at least as long as distance between them. Adanal discs slightly elliptical, diameter
13x12
(
12x11–15
x12); each disc with small antero-medial sclerite. Corollae of discs radially striated. Distances between setae:
3b–3b
120 (64–111),
3b–3a
41 (30–44),
3a–g
68 (50–66),
g–ps3
38 (35–42),
ps3–ps2
70 (68–74).
FIGURE 2.
Distal podomeres of
Glaucalges tytonis
sp. n.
, dorsal view, male. Designations of setae after Gaud and Atyeo (1996). A – tarsus I, B – tibia and tarsus II, C – tarsus III, D – tarsus IV.
Legs I–II of similar size, legs III longer than I–II, legs IV thicker than others. Tibiae I and II with ventral triangular apophyses. Femoragenua I and II with rounded dorsal retrograde apophyses. Tarsi II and III elongated with narrow ventral lamella. Tarsus IV short with two apical spines, tarsus III with single apical spine. Ambulacra I well developed, II–IV vestigial. Tips of leg IV tibiae reaching level of posterior margins of terminal membranes. Setae
ba
absent on tarsi I–II,
r, s
on tarsi III, and
r, e
on tarsi IV; setae
d
on tarsi IV sticklike, very short (
Fig. 2
A–D).
Female
(
Figs 3
,
4
,
5
C). Gnathosoma shaped as in males, length 48–50, width 47–50, length/width 1.0– 1.1. Idiosoma moderately elongated, parallel-sided, length 310–315, width 149–160, length/width 2.0–2.1.
Propodosoma and hysterosoma lengths 92–105 and 210–218 respectively, propodosoma/hysterosoma 0.4– 0.5. Rounded or concave terminal margin with small terminal protuberance with copulatory opening on its tip; in some individuals copulatory opening situated more dorsally in which case protuberance is absent. Pronotum shaped and sclerotized as in male, pronotal shield length 92–96, width 85–92. Humeral shields absent. Hysteronotal shield shaped as strongly elongated trapezium, anterior margin longer than posterior one, both margins concave. Shield extends posteriorly slightly beyond the level of setae
e2
; length of the shield 149– 153, width at anterior margin 78–83. Two elongated lacunae lying medially to bases of setae
d2
. All dorsal shields uniformly dotted. Setae of pronotum as in males. Setae of dorsal hysterosoma short and with exception of
d2
inserted on striated tegument outside the hysteronotal shield; setae
d
2
set on lateral margins of the shield. Setae
e1
nearly twice as long as
d2
(
Fig. 5
C). Distances between setae:
c2–c2
125–135,
c2–d2
64–68,
d2–d2
70–74,
d2–
e2
91–92,
e2–
e2
67–76,
h3–h3
44–57.
FIGURE 3.
Glaucalges tytonis
sp. n.
, female. A – ventral view, B – dorsal view. CO – copulatory opening.
Ventral propodosoma shaped and sclerotized as in male. Epigynum well developed, arched, width 42–43, height 18–22 (max.
30 in
additional material) (
Figs 3
A, 4). Branches of epigynum encompassing bases of setae
3a
. Latigenital sclerites extending posteriorly beyond the level of genital setae
g.
Setae
g
inserted posterior to the level of genital acetabula and posterior to the level of setae
3b
. Setae
3b
anterior to genital acetabula. Setae
ps2
inserted latero-terminal to
ps3
,
ps3
subequal to
ps
2
in length.
Ambulacra of legs IV reaching terminal end of the body, legs III do not reach body terminus. Both posterior tarsi attenuate with narrow ventral lamella.
FIGURE 4.
Epigynum and oviporus in female
Glaucalges tytonis
sp. n.
GA—genital acetabula.
Differential diagnosis.
Morphology.
The new species is extremely similar to
Glaucalges attenuatus
(
Buchholz, 1869
)
described from the long-eared owl
Asio otus
(
Strigiformes
,
Strigidae
). Males of both species differ by length of dorsal setae
d2
and
e2
: in
G. tytonis
sp. n.
these setae are much longer than in
G. attenuatus
(
Figs 5
A, 6). Females are almost indistinguishable. The only difference is in the relative lengths of setae
d2
and
e2
: in females of
G. t y t o n i s
sp. n.
setae
e2
are clearly almost twice as long as setae
d2
; in
G. attenuatus
both setae are subequal (
Fig. 5
C). Both sexes of
G. tytonis
sp. n.
have Y-shaped epimerites I with short sternum, while G.
attenuatus
has these sclerites V-shaped (
Fig. 5
B). Males of
G. tytonis
sp. n.
are larger on average than
G. attenuatus
: 360x220 versus 330x200 (
Fig. 7
). However the shape of epimerites and the body size may sometimes fail as distinguishing characters.
DNA barcode.
We amplified and sequenced a 644 bp fragment of the cytochrome oxidase subunit I (COI) gene (DNA barcode region chosen by the Consortium for the Barcode of Life, http://barcoding.si.edu) for one male
holotype
and
3 male
paratypes
(Acc.
EU271955
), remaining
paratypes
(Acc.
EU271956
) as well as for specimens of
G. attenuatus
(Acc.
EU271957
,
EU271958
). Intraspecific K2P divergence in
G. attenuatus
was 0.47%. No intraspecific variability in
G. tytonis
sp. n.
was detected. Comparison of the sequences from
Glaucalges tytonis
sp. n.
and
G. attenuatus
showed that proportion of different nucleotides ranged from 14.65% to 14.85% (mean 14.75%). Because most of the nucleotide substitutions were synonymous, they resulted only in one amino acid change (substitution of valine with isoleucine). This observed genetic distance in the nucleotide sequence of the DNA barcode is substantial, with the differentiation between species comparable to the majority of currently recognized species (
Hebert
et al.
2003
).
FIGURE 5.
Morphological differences between
Glaucalges tytonis
sp. n.
(left) and G.
attenuatus
(right). A – male hysteronotum, B – epimerites I of male, C – female hysteronotal shield with associated setae.
Etymology.
The specific epithet is derived from the generic name of the host
Tyto alba
.
Remarks.
Although DNA extraction from a single individual of feather mite is technically possible we suggest in case of small-sized mites such as these
Glaucalges
species (less than
0.5 mm
) to publish DNA barcode sequence isolated from a sample of several individuals (
holotype
and
paratypes
= “
type
sample”) along with information about possible genetic variability.
Results of the present study seem to confirm our previous observations that multihost feather mite species are often in fact a group of cryptic species. Each of these species is associated with limited host range of closely related bird species or even with a single host species (
Badek & Dabert 2006
,
Dabert
et al.
2005
). If this evolutionary scenario holds true, it is likely that the
Glaucalges
species recorded on other strigid owls may also represent different species of mites. In our opinion, only thorough morphological analysis accompanied by DNA barcoding will significantly accelerate studies that could resolve this and many similar taxonomic problems.
FIGURE 6.
Length of setae
d2
and
e2
in males of
Glaucalges tytonis
sp. n.
and
G. attenuatus
.
FIGURE 7.
Idiosoma dimensions in
Glaucalges tytonis
sp. n.
(white circles, N=12) and
G. attenuatus
(black circles, N=12).
TABLE 1.
Host range of known
Glaucalges
species.
Mite species Hosts Locality References
G. attenuatus
Strigiformes
(Buchholz)
Strigidae
Aegolius funereus
(L.)
Germany
Eichler (1938)
Asio flammeus (
Pontoppidan)
Germany
Buchholz (1869)
Asio otus
(L.)
Morocco
Gaud (1980)
Germany
Buchholz (1869)
Athene noctua
(Scopoli)
Rhodesia
,
Zaire
, Zululand
Gaud (1980)
Morocco
Gaud (1958)
Bubo africanus
(Temminck)
Rwanda
,
Zaire
, Zululand
Gaud (1980)
Bubo bubo
(L.)
Zaire
Gaud (1980)
Finland
Lönnfors (1937)
Switzerland
Mumcuoglu and Müller (1974)
Bubo lacteus
(Temminck)
Rwanda
,
Zaire
Gaud (1980)
Bubo leucostictus
Hartlaub
Zaire
Gaud (1980)
Bubo poensis
Fraser
Morocco
Gaud (1958)
Zaire
Gaud (1980)
Cameroon
Gaud and Mouchet (1959)
,
Gaud and Till (1961)
,
Gaud (1980)
Bubo shelleyi
(Sharpe et
Zaire
Gaud (1980)
Ussher)
Bubo virginianus
(Gmelin)
USA
Atyeo and Philips (1984)
Cameroon
Gaud (1980)
Scotopelia peli
(Bonaparte)
Cameroon
Gaud and Till (1961)
,
Gaud (1980)
Strix aluco
(L.) no data
Philips (2007)
Strix woodfordii
(Smith A.)
Cameroon
Gaud (1980)
G. ty t on is
sp. n.
2
Tytonidae
Tyto alba
(Scopoli)
Poland
,
Germany
present study
Morocco
Gaud and Petitot (1948)
,
Gaud (1958)
Senegal
Gaud and Mouchet (1959)
,
Gaud and Till (1961)
,
Gaud (1980)
Cameroon
, Transvaal
Gaud (1980)
United Kingdom
Rothschild and Clay (1952)
Cuba
Č erný (1967)
Japan
McClure and Ratanaworabhan (1973)
1
India
Philips (2007)
G. pteropus
Musophagiformes
(Gaud et Mouchet)
Musophagidae
Corythaeola cristata
(Vieillot))
S
Cameroon
Gaud and Mouchet (1959)
,
Gaud and Atyeo (1981)
1 Designed as
Protalges
sp. only.
2 Provisional designations without checking the material described under name
Glaucalges attenuatus
(except present study).