A new species of Loxosceles of the laeta group from Brazil (Araneae: Sicariidae)
Author
Martins, Rosana
Author
Knysak, Irene
Author
Bertani, Rogério
text
Zootaxa
2002
2002-11-05
94
1
6
journal article
http://doi.org/10.5281/zenodo.4620264
6d958c1b-d741-4a23-b0f6-cab6acc723ea
11755326
4620264
62575399-8CDD-4108-8722-71536ABE24D6
Loxosceles puortoi
sp. nov.
Figs.
1–7
.
Holotype
male (
IBSP
34728
) and
paratype
female (
IBSP
34729
) from Tatu Cave, Palmas, Tocantins,
Brazil
(
09°
59
'
10
''S
,
48
°
19
'
20
''W
),
16
.vi.
2001
, R. Martins, I. Knysak & G. Puorto coll.
Etymology.
The specific name is a patronym for the Brazilian herpetologist Giuseppe Puorto for his efforts in helping to collect the
type
specimens.
Diagnosis.
Males can be readily recognized from other species by the very narrow palpal femur and tibia: the palpal femur is about
11
times longer than wide and the palpal tibia about
5
times longer than wide (
Figs. 3, 4
). Females can be distinguished from all other species except
L
.
coquimbo
Gertsch,
1967
,
L
.
virgo
Gertsch & Ennik,
1983
,
L
.
lawrencei
Caporiacco,
1955
and
L
.
rufipes
(Lucas,
1834
)
by the presence of four spermathecae (
Fig.
5
). It is distinguished from
L
.
coquimbo
by not having the tibia and tarsus of the palp incrassate and by leg II being longer than leg IV; from
L
.
lawrencei
and
L
.
rufipes
by not having the two spermathecae of each side largely fused in the basal portion; and, from
L
.
virgo
by having the two spermathecae of each side with similar width.
FIGURES 1–5.
Loxosceles
puortoi
. (1–2) Carapace. 1, paratype female; 2, holotype male. (3–4) right male palp (holotype). 3, retrolateral view; 4, prolateral view. 5, female paratype, spermathecae. Scale bars = 1 mm.
Description.
Male
(
Holotype
). Total length
5.2
. Carapace
2.4
long,
2.3
wide. Eye sizes: ALE:
0.13
, PME:
0.15
, PLE:
0.13
. Clypeus equal in width to two and onehalf diameters of PME. Distance between PME and PLE equal to
0.33
diameters of PME. PME separated from ALE by
1.3
diameters of former. Leg formula II, IV, I, III. Leg I: femur
4.3
/ patella
0.7
/ tibia
4.9
/ metatarsus
4.8
/ tarsus
1.2
/ total
15.9
/ II:
4.9
/
0.9
/
6.2
/
6.3
/
1.2
/
19.5
/ III: 4.0 /
0.8
/
3.8
/
4.7
/
0.9
/
14.2
/ IV:
4.3
/
0.8
/
4.4
/
5.7
/
1.1
/
16.3
. Leg I
6.6
times as long as carapace; femur I
1.8
times as long as carapace. Metatarsus I without a sinuous curve in the middle portion. Palpal femur
11.6
times longer than wide, palpal tibia
5.7
times longer than wide; cymbium slightly elongated. Bulb suboval in side view, shorter than cymbium. Embolus curved, twice as long as bulb width, without carina. Carapace covered by many short, curved setae.
Carapace with pars cephalica and border dark brown, contrasting with olive brown pars thoracica. Legs olive brown.
Female
(
Paratype
). Total length 8.0. Carapace 3.0 long,
2.6
wide. Eye sizes: ALE:
0.15
, PME:
0.15
, PLE:
0.13
. Clypeus equal in width to two and onehalf diameters of PME. Distance between PME and PLE equal to
0.37
diameters of PME. PME separated from ALE by
1.4
diameters of former. Leg formula: II, IV, I, III. Leg I: femur
3.9
/ patella
0.9
/ tibia
3.8
/ metatarsus
3.7
/ tarsus
1.1
/ total
13.4
/ II:
4.2
/
0.9
/
4.2
/
4.3
/
1.1
/
14.7
/ III:
3.6
/
0.9
/
3.1
/
3.6
/
0.9
/
12.1
/ IV:
3.9
/
0.9
/
3.7
/
4.4
/ 1.0 /
13.9
. Leg I
4.5
times as long as carapace. Femur I
1.3
times as long as carapace. Palpal tarsus not incrassate. Four tubular spermathecae, the internal ones having a curvature in the distal portion (
Fig.
5
). Colour pattern as in male, except the palpal tibia and tarsus, which are reddish brown.
Additional material examined:
Brazil
,
Tocantins
: Palmas, Tatu Cave (
09°
59
'
10
''S
,
48
°
19
'
20
''W
),
16
.vi.
2001
, R. Martins, I. Knysak & G. Puorto coll.,
10
females
(
IBSP
34730
); same locality and collectors,
11–19
.viii.2001
,
1 male
(
IBSP
34731
); Miracema do Tocantins (
09°
45
'
23
''S
,
48
°
22
'
58
''W
), same collectors,
17–25
.iv.2002
,
1 female
(
IBSP
34732
). Besides the preserved material,
22
living specimens are being kept at the Laboratório de Artrópodes of the Instituto Butantan.
Distribution.
Brazil
: Palmas and Miracema do Tocantins, State of Tocantins.
Discussion.
The new species can be included in the
laeta
group of
Gertsch (
1967
)
based on details of genitalia. These are: bulb of palpus suboval, embolus longer than diameter of bulb, absence of wing or carina in the embolus, and tibia of palpus at least twice as long as cymbium in male. Female has four tubular spermathecae closely positioned, free, and without a cluster of small globular lobes at apex (
Fig.
5
).
Of the four groups of species of the South American
Loxosceles
fauna proposed by
Gertsch (
1967
)
, only the
laeta
group did not have native species in
Brazil
. The only species occurring in the country was
L
.
laeta
, which seems to have been introduced either from
Peru
or
Chile
(
Gertsch & Ennik
1983
). The group is particularly speciose in the Andean region of South
America
, mainly
Peru
, from where
17
of the
24
species were described (
Gertsch
1967
).
FIGURE.
6.
Loxosceles puortoi
. Holotype male. Photo: R. Bertani.
FIGURE.
7.
Loxosceles puortoi
. Female. Photo: R. Bertani.
Natural History.
Specimens of
Loxosceles puortoi
were collected in the mountain range of Lajeado at an altitude of
240 m
.
The predominant vegetation is the savannah-like ‘cerrado’. This is intermixed with gallery forest with trees
20–30 m
in height. The soil is a
sandy clay with a dense litter layer. This area is underlain by a sedimentary rock formation, in which there is a small cave (
5
x
1.7
x
2.5 m
). Adults and immatures of
L
.
puortoi
were found under rocks and inside rock crevices, both inside and outside the cave. The females build a loose web roughly
100 mm
in diameter. Immatures, probably in the
4
th or
5
th instars, were found both in the litter and under small rocks. Remains of ants (
Hymenoptera
:
Formicidae
) were found in great quantities attached to the webs.