Seven new species of the spider genus Matta Crosby from caves in the State of Minas Gerais, Brazil (Araneae, Tetrablemmidae)
Author
Brescovit, Antonio D.
Author
Cizauskas, Igor
text
Zootaxa
2019
2019-02-21
4559
3
401
444
journal article
27445
10.11646/zootaxa.4559.3.1
2dac93f3-40be-45f8-ba84-10026f56a001
1175-5326
2627047
10CDA291-A32F-4954-9B80-E33579AF46E3
Matta humhum
sp. n.
Figures 10
̄14, 30C.
Types.
Male
holotype
and female
paratype
from Cave AP_066 (
43°40'17''W
20°0'32''S
), Caeté,
Minas Gerais
,
Brazil
,
12-21/XI/2009
, R. Bessi
et al
. col., deposited in IBSP 179486 and IBSP 179487, respectively.
Other material examined.
Brazil
.
Minas Gerais
:
Caeté
,
Cave
AP_049 (
43°41'29''W
20°2'8''S
),
12-21/XI/ 2009
,
R. Bessi
et al
. col.,
1♀
(
IBSP 179488
)
;
Cave
AP_038 (-43.67925100 -20.03098600), epygean,
07-13/VIII/ 2012
,
R. Andrade
&
G. P. Perroni
et al
. col.,
1♂
(
IBSP 186423
)
;
Cave
AP_049 (
43°41'29''W
20°2'8''S
),
31/V-05/
VI
/2012
,
R. Bessi
et al
. col.,
1♂
1 ♀
(
IBSP 186427
; photo)
;
Cave
AP_066 (
43°40'17''W
20°0'32''S
),
31/V-05/
VI
/ 2012
,
R. Bessi
et al
. col.,
1♂
(
IBSP 186429
)
;
Barão de Cocais
,
Cave
RF
_009 (
43°29'13''W
19°55'6''S
),
926 m
, 10-
21/III/2
0 0 9,
2♀
(
IBSP 186411
)
;
Cave
RF
_058 (
43°41'8''W
20°1'34''S
),
1342 m
,
10-21/III/2009
,
1♂
(
IBSP 186414
)
;
Cave
RF
_005 (
43°29'10''W
19°55'3''S
),
948 m
,
10-21/III/2009
,
1♂
(
IBSP 186415
)
, all collected by R. Andrade
et al
.; Cave
RF
_057 (
43°41'8''W
20°1'34''S
),
1331 m
,
22/VI-03/VII/2009
, R.
Bessi
et al
. col.,
1♀
(
IBSP 186412
)
;
Cave
RF
_069 (
43°40'9''W
20°0'35''S
),
1502 m
,
09-13/XII/2009
, R.
Bessi
et al
. col.,
1♂
(
IBSP 186413
)
;
Itabirito
,
Mina do Pico
, 2013,
1♂
1♀
(
IBSP 186394
,
IBSP 186395
,
IBSP 186397
)
;
Mariana
,
Cave
GER_0052 (
20°17'25''S
;
43°22'26''W
),
15/IX-01/X/2015
,
1♀
(
IBSP 186517
)
;
Cave
SM
_63 (
20°13'51''S
;
43°23'44''W
),
11-23/ VIII/2014
,
1♂
(
IBSP 186518
)
;
Cave
SM
_82A (
20°13'38''S
;
43°27'43''W
),
30/IX-04/X/2013
,
2♀
(
IBSP 186519
–
SEM
1
♀)
,
all collected by
Eq. Carste
col.;
Cave
SM
,
13/XII/2012
,
1♀
(
IBSP 189177
)
;
Cave
FN-012 (
43°26'19''W
20°12'29''S
),
18/XII/2012
,
1♂
(
IBSP 189178
)
;
Cave
FN-010 (
43°26'19''W
20°12'27''S
),
09/XII/2012
,
1♂
(
IBSP 189179
)
,
Cave
FN-012 (
43°26'19''W
20°12'29''S
),
09/XII/2012
,
1♂
3♀
(
IBSP 189180
)
,
all collected by
BioEspeleo Consultoria Ambiental
;
Cave
FN_12 (
20°12'29''S
;
43°26'19''W
),
16-21/I/2009
,
1♂
(
IBSP 146209
)
;
Cave
FN_15 (
20°12'20''S
;
43°26'9''W
),
5-9/V/2009
,
1♂
(
IBSP 146258
)
;
Cave
FN_07 (
20°12'37''S
;
43°26'21''W
),
5-9/V/2009
,
1♂
(
IBSP 146179
—
SEM
♂
)
;
Cave
FN_20,
3-7/II/2011
,
1♂
(
IBSP
)
,
all collected by
R. Andrade
;
Santa Bárbara
,
Cave
APOL
_28 (
43°40'8''W
20°0'56''S
),
30/VI-08/VII/2011
,
R. Bessi
et al
. col.,
1♀
(
IBSP 186424
)
;
Cave
APOL
_28 (
43°40'8''W
20°0'56''S
),
05-09/XII/2011
,
R. Bessi
et al
. col.,
1♂
(
IBSP 186426
)
.
Etymology.
The specific name is a noun in apposition that refers to an expression used by people in the Brazilian State of
Minas Gerais
meaning “no”, and in this case indicates that the species is not blind but has vestigial eyes.
Diagnosis.
Matta humhum
is distinguished from other
Matta
species by having a combination of males with a leg I with retrolateral projection on a raised base, with four conspicuous setae in elevated sockets in the male (
Fig 12A
̄D) and mushroom shape dorsal fold of the uterus externus in females (
Fig. 10F
).
Description.
Male
(
Holotype
, IBSP 179486). Cephalothorax and abdomen orange. Legs and pedipalps yellow (
Fig. 10A
). Total length 1.07. Carapace projected, 0.47 long, 0.4 wide, with rugose surface (
Fig. 11A, C
). Sternal surface tenuously reticulate. Clypeus long, oblique, four times the diameter of the vestigial eyes (
Fig. 11A
). Eye almost vestigial, diameters and interdistances: AME 0.04, AME-AME 0.08 (
Figs. 10A
,
11A
). Cheliceral apophysis short, conical, in the middle area, with long hairs and translucent median lamina (
Fig. 11B
̄C). Leg measurements: I—femur 0.36/ patella 0.13/ tibia 0.28/ metatarsus 0.17/ tarsus 0.23/ total 1.17; II—0.32/ 0.13/ 0.24/ 0.16/ 0.18/ 1.03; III—0.26/ 0.12/ 0.2/ 0.16/ 0.2/ 0.94; IV—0.42/ 0.12/ 0.31/ 0.22/ 0.23/ 1.3. Leg formula 4123. Leg I, spination absent; metatarsus narrowed at base (
Fig. 12A
̄D). Trichobothria as in
M. zuiuda
(
Fig. 12E
).
Abdomen
ovoid, large sclerotized plate covering dorsal surface (
Fig. 11D
); ventrally covered by four sclerotized plates (
Fig. 11E
).
Abdominal plates:
large pulmonary plate with rounded anterior margin, surrounding pedicel and bearing oval book-lung plates, followed posteriorly by very narrow postgenital plate, suboval preanal plate, and conical anal plate surrounding spinnerets; laterally with four pairs of narrow plates, with same length (
Fig. 11D
), and a line of the four epiandrous spigots (
Fig. 11F
).
Male palp
with femur with three long setae, median short and projected salient plates (
Fig. 12F
); tibia strongly swollen, rounded posteriorly; cymbium small; bulbus pear-shaped, with conductor with short border, involving the base of the embolus long, curved in the posterior third area and enlarged at apex, with acute and short basal laminar projection (
Fig. 13A
̄F).
FIGURE 10
.
Matta humhum
sp. n.
, male IBSP 186427 (
A–C
), female IBSP 186427 (
D‒F
)
A
habitus, dorsal view
B
palp, retrolateral view
C
same, prolateral view
D
habitus, dorsal view
E
abdomen, ventral view
F
vulva, cleared, dorsal view.
FIGURE 11
.
Matta humhum
sp. n.
, male IBSP 196173 (
A–C
)
A
carapace, frontal view
B
chelicerae, frontal view
C
same, lateral view
D
abdomen, lateral view
E
same, ventral view
F
same, epiandrous area, ventral view.
FIGURE 12
.
Matta humhum
sp. n.
, male IBSP 196173 (
A–C
)
A‒B
leg I, tibiae+metatarsus, retrolateral view
C
tibiae I, dorsal view
D
leg I, tibiae+metatarsus, ventral view
E
tibiae I, tricobothrium, dorsal view
F
male palp, tibiae, prolateral view.
FIGURE 13
.
Matta humhum
sp. n.
, male palp, IBSP 196173 (
A–F
),
A
prolateral view
B
detail of apex, prolateral view
C
retrolateral view
D
detail of apex, retrolateral view
E
ventral view
F
detail, ventral.
FIGURE 14
.
Matta humhum
sp. n.
, female IBSP 186519 (
A–F
),
A
carapace, frontal view
B
same, lateral view
C
carapace, setae dorsal, lateral view
D
thoracic groove, detail, dorsal view
E
carapace, lateral view
F
pedipalp, distal area
G
abdomen ventral area
H
same, vulva plate.
Female
(
Paratype
, IBSP 179487). Coloration pattern as in male (
Fig. 10D
). Total length 1.15. Carapace slightly most projected that in male, with long median dorsal setae and fovea with 4-5 small rounded projections (
Fig. 14A
̄E); 0.47 long, 0.38 wide. Clypeus and sternum as in male. Eye diameters and interdistances as in male. Chelicerae without apophysis, with ventral translucent hyaline keel as in male (
Fig. 14A
). Leg measurements: Ifemur 0.36/ patella 0.12/ tibia 0.26/ metatarsus 0.16/ tarsus 0.23/ total 1.13; II—0.32/ 0.11/ 0.23/ 0.15/ 0.22/ 1.03; III—0.23/ 0.11/ 0.19/ 0.16/ 0.2/ 0.89; IV—0.38/ 0.12/ 0.32/ 0.2/ 0.21/ 1.23. Leg formula 4123. Leg spination absent. Pedipalpal tarsus ending in acuminate, smooth pit (
Fig. 14F
).
Abdomen
with plates as in male (
Fig. 14G
). Vulvae externally with ᴗ-shaped receptacle, visible by transparency (
Fig. 10E
); narrow post genital plate and thin copulatory opening (
Fig. 14H
). Internally with enlarged receptaculum and narrow at base copulatory ducts; central process narrow, with length of the receptaculum (
Fig. 10F
).
Natural history
.
Matta humhum
sp. n.
is a species known only from caves in the ferruginous formations of the Quadrilátero Ferrífero Iron Region. Specimens were collected in both aphotic and twilight zones and always on the cave floor. Based on reduced eyes and long hairs of trichobothria we hypothesize that this species is a troglobite.
Distribution.
Known from caves in Quadrilátero Ferrífero Iron Region in the State of
Minas Gerais
,
Brazil
(
Fig. 30C
).