New and interesting species of the generaGalumna andPergalumna (Acari, Oribatida, Galumnidae) from the Montagne d’Ambre National Park, Madagascar
Author
Ermilov, Sergey G.
Institute of Environmental and Agricultural Biology (X-BIO), Tyumen State University, Tyumen, Russia.
Author
Starý, Josef
Biology Centre v. v. i., Czech Academy of Sciences, Institute of Soil Biology, České Budejovice, Czech
text
Acarologia
2020
2020-01-17
60
1
64
74
journal article
21703
10.24349/acarologia/20204357
621e183b-789b-4d5e-bc43-64000219e1a8
2107-7207
3890497
Galumna
(
Galumna
)
sandormahunkai
n. sp.
Zoobank:
98E9F2F2-5384-4E4D-BADE-C6A461B64755
(
Figures 1–3
)
Diagnosis
— Body size 780–996 × 564–780. Rostrum protruding, narrowly rounded. Lamellar and sublamellar lines divergent distally,
L
directed to lateral sides of prodorsum,
S
curving backwards. Rostral and lamellar setae of medium size, setiform, slightly barbed. Interlamellar setae minute. Bothridial setae long, narrowly lanceolate, barbed. Dorsosejugal porose areas present. Dorsosejugal suture complete. Four pairs of small porose areas,
Aa
oval, others rounded. Median pore absent. Epimeral setal formula 1-0-1-2. Epimeral and anogenital setae short, setiform, roughened. Circumpedal carinae short. Postanal porose area narrowly elongate oval. Solenidion on tibiae IV inserted in anterior part of the segment.
Description
— Measurements – Large species. Body length 996 (
holotype
, female), 780– 996 (
13 paratypes
,
10 females
and three males); notogaster width 763 (
holotype
), 564–780 (
13 paratypes
). Females larger than males: 946–996 × 747–780 versus 780–846 × 564–614.
Integument – Body color light brown to brown. Body surface densely microgranulate, granules (less than 1) poorly developed (visible only at high magnification
x1000
). Antiaxial sides of all leg femora and trochanters III, IV with rounded and elongated tubercles.
Prodorsum (
Figs 1a
,
2a, 2c
) – Rostrum strongly protruding (visible in frontal view), narrowly rounded. Lamellar and sublamellar lines slightly divergent distally,
L
thickened, directed to lateral sides of prodorsum,
S
thin, curving backwards. Lateral structures
N
and ridges
E
and
T
well developed. Rostral (49–53) and lamellar (49–53) setae setiform, slightly barbed. Interlamellar setae very short (4–6), setiform, thin, smooth. Bothridial setae (159–168) with long stalk and short, narrowly lanceolate, barbed head. Exobothridial setae represented by alveoli. Dorsosejugal porose areas (24–32 × 4–6) elongate oval, transversely oriented, located posterior or posterolateral to
in
. Dorsophragmata slightly elongated longitudinally.
Notogaster (
Figs 1a
,
2a, 2b
) – Dorsosejugal suture complete. With 10 pairs of setal alveoli or vestigial setae (up to 1) and four pairs of small porose areas having distinct borders,
Aa
(22–26 × 10–12) oval,
A1
,
A2
and
A3
(10–20) rounded. Porose areas
Aa
located close to pteromorphal hinges, anteriorly to
la
. Median pore absent in females and males. Opisthonotal gland openings and all lyrifissures distinct,
gla
located anterolateral to
A1
and removed from them,
im
anterior to
A1
and slightly removed from them,
ip
lateral to
p
1
,
ih
anterior to
p
3
,
ips
lateral to
p
3
.
Gnathosoma (
Figs 2
d-f) – Subcapitulum size 196–205 × 180–192. Subcapitular setae (
a
, 32;
m
, 32;
h
, 24) setiform, slightly barbed;
a
thickest,
h
thinnest. Adoral setae (24) setiform, barbed. Length of palps 139–143. Postpalpal setae (8) spiniform, smooth. Length of chelicerae 237–241. Cheliceral setae (
cha
, 82–86;
chb
, 45–49) setiform, barbed. Trägårdh’s organ of chelicerae long, elongate triangular.
Figure 1
Galumna sandormahunkai
n. sp.
, adult: a – dorsal view; b – ventral view (gnathosoma and legs omitted). Scale bar 100 μm.
Figure 2
Galumna sandormahunkai
n. sp.
, adult: a – anterior part of body, lateral view (gnathosoma and legs omitted); b – posterior part of body, lateral view; c – anterior part of prodorsum, frontal view; d – subcapitulum, ventral view; e – palp, right, antiaxial view; f – chelicera, left, paraxial view. Scale bar 100 μm (a, b), scale bar 50 μm (c, d, f), scale bar 20 μm (e).
Epimeral and lateral podosomal regions (
Figs 1b
,
2a
) – Anterior margin of epimere I smooth. Epimeral setal formula 1-0-1-2. Epimeral setae setiform, thin, roughened,
3b
(30–32) longer than
1b
,
4a
and
4b
(18–20). Pedotecta I broadly rounded, pedotecta II quadringular in ventral view. Discidia triangular. Circumpedal carinae short, thin, directed to acetabula IV.
Anogenital region (
Figs 1b
,
2b
) – Six pairs of genital setae
g
1
, (
g
2
, 26–28;
g
3
–
g
6
, 18–20), one pair of aggenital (18–20), two pairs of anal (18–20) and three pairs of adanal (18–20) setae setiform, thin, roughened. Anterior edge of genital plates with two setae. Aggenital setae located between genital and anal apertures, nearer to genital aperture. Adanal lyrifissures located close and parallel to anal plates. Adanal setae
ad
1
and
ad
2
posterior,
ad
3
lateral to anal aperture. Distance
ad
1
–
ad
2
slightly shorter than
ad
2
–
ad
3
. Unpaired postanal porose area narrowly elongate oval (41–49 × 4–6).
Legs (
Figs 3a, 3b
) – Median claw distinctly thicker than lateral claws, all slightly barbed on dorsal side. Porose area on all femora and on trochanters III, IV well visible. Formulae of leg setation and solenidia I (
1-4-3-4-20
) [1-2-2], II (
1-4-3-4-15
) [1-1-2], III (
1-2-1-3-15
) [1-1-0], IV (
1-2-2-3-12
) [0-1-0]; homology of setae and solenidia indicated in
Table 1
. Famulus on tarsi I inserted between solenidia ω
1
and ω
2
. Solenidion on tibiae IV inserted in anterior part of the segment.
Material examined
—
Holotype
(
female
) and 13
paratypes
(
10 females
and three
males
): North
Madagascar
,
Montagne
d’Ambre
National Park
, circuit
Ampijoroana
, evergreen rain forest,
12°31’28”S
,
49°09’52”E
,
950 m
a.s.l.,
sifting of leaf litter sample under big unidentified tree
,
Winkler apparatus extraction
,
13.I.2014
(R. Ravebolun and L. Rabotenoson)
.
Type
deposition
— The
holotype
and two
paratypes
are deposited in the collection of the Senckenberg Institute, Görlitz,
Germany
.
Eleven
paratypes
are deposited in the collection of the
Tyumen State
University Museum of Zoology,
Tyumen
,
Russia
. All specimens are preserved in ethanol with drop of glycerol.
Etymology
— The new species is named after late Prof. Dr. S. Mahunka, the Hungarian acarologist, for his extensive contributions to our knowledge of oribatid mites.
Remarks
— In the presence of long rostral and lamellar setae, short interlamellar setae, long bothridial setae with developed head, complete dorsosejugal suture, and four pairs of rounded notogastral porose areas,
Galumna sandormahunkai
n. sp.
is morphologically most similar to
Galumna sphagni
Ermilov, Hugo-Coetzee and Theron, 2018
from South Africa, but differs from the letter by the larger body size (780–996 × 564–780 versus 415–431 × 315–332), the presence of strongly protruding rostrum (versus not protruding), lanceolate, pointed apically bothridial setae (versus unilaterally dilated, rounded apically), the direction of lamellar lines to lateral sides of the prodorsum (versus anterior part of the ventral plate), and the absence of median pore (versus present).