On Venezuelan pholcid spiders (Araneae, Pholcidae)
Author
Huber, Bernhard A.
33607F65-19BF-4DC9-94FD-4BB88CED455F
Zoological Research Museum Alexander Koenig, Bonn, Germany.
b.huber@leibniz-zfmk.de
Author
Villarreal, Osvaldo
679C385E-B068-4351-9D2F-97753E534C26
Museo del Instituto de Zoología Agrícola, Universidad Central de Venezuela, Maracay, Venezuela. & Museu Nacional / UFRJ, Rio de Janeiro, Brazil.
osvaldovillarreal@gmail.com
text
European Journal of Taxonomy
2020
2020-10-01
718
1
317
journal article
10.5852/ejt.2020.718.1101
4069574
F9E9A91E-488C-4DB1-9361-E788E9AC5BC1
Mecolaesthus alegria
Huber
sp. nov.
urn:lsid:zoobank.org:act:
DB90E250-72DE-47EB-ACB1-4A4D1C11E22D
Figs 476–478
,
488–493
, 1044
Diagnosis
Easily distinguished from most known congeners (except
M. pusillus
Huber
sp. nov.
) by armature of male chelicerae (
Figs 491–492
; pair of large frontal apophyses set with large modified hairs and pair of simple distal apophyses), by shape of procursus (identical to
M. pusillus
Huber
sp. nov.
, cf.
Figs 479– 481
; without retrolateral process; tip with pair of dark sclerites connected by transparent membrane), and by epigynum with pair of dark internal structures distinct in uncleared specimens (
Fig. 476
). From very similar
M. pusillus
Huber
sp. nov.
by details of male cheliceral armature (large frontal apophyses directed forward rather than downward; simple distal apophyses with accompanying globular hairs), by shape of bifid distal bulbal sclerite (
Figs 488–490
; dorsal sclerite much wider in dorsal view), by shape of epigynum (
Fig. 476
; wider than long), and by internal female genitalia (
Figs 477–478
,
493
; shape of large lateral ear-shaped structures). From most known congeners (except
M. pusillus
Huber
sp. nov.
,
M. arepa
Huber
sp. nov.
, and
M. guasacaca
Huber
sp. nov.
) also distinguished by distinct median process posteriorly on male carapace.
Etymology
The species name refers to the
type
locality; noun in apposition.
Type
material
VENEZUELA
–
Falcón
•
♂
holotype
,
ZFMK
(Ar 21938),
forest near Santa Cruz de La Alegría
(
10.8795° N
,
68.4949° W
),
100 m
a.s.l.
,
15 Feb. 2020
(
B.A. Huber
,
O. Villarreal
M.,
Q. Arias
C.)
.
Other material examined
VENEZUELA
–
Falcón
•
1 ♀
in pure ethanol (abdomen transferred to male holotype),
ZFMK
(Ven20- 147), same collection data as for holotype
.
Description
Male
(
holotype
)
MEASUREMENTS. Total body length 2.8, carapace width 0.95. Distance PME–PME
90 µm
; diameter PME
90 µm
; distance PME–ALE
50 µm
; diameter AME
20 µm
; distance AME–AME
20 µm
. Leg 1: 31.1 (7.4 +0.4 +7.6+13.8 + 1.9), tibia 2: 4.9, tibia 3: 3.9, tibia 4: 4.5; tibia 1 L/d: 95.
COLOR (in ethanol). Carapace pale ochre with darker median band and lateral marginal bands
not
connected posteriorly, ocular area and clypeus dark ochre; sternum ochre-yellow; legs ochre-yellow to light brown, without dark rings; abdomen pale greenish gray, dorsally and laterally densely covered with dark bluish marks, ventrally with small brown mark in gonopore area and bluish median band behind gonopore; book lung covers light brown; with small light brown plate above pedicel.
BODY. Habitus as in
M. pusillus
Huber
sp. nov.
(cf.
Fig. 471
). Ocular area slightly raised. Carapace anteriorly with shallow but distinct thoracic groove, posteriorly
not
inflated but with distinct median process. Clypeus unmodified. Sternum wider than long (0.62/0.40), unmodified. Abdomen slightly elongated, pointed at spinnerets.
CHELICERAE. As in
Figs 491–492
, similar to
M. pusillus
Huber
sp. nov.
but larger, with pair of large frontal apophyses, each provided with three large modified hairs near tip and two large modified hairs proximally, and pair of simple distal apophyses, each accompanied by globular hair.
Figs 488–493.
Mecolaesthus alegria
Huber
sp. nov.
; from Falcón, Santa Cruz de La Alegría (type locality; ZFMK Ar 21938).
488–490
. Left genital bulb, prolateral, dorsal, and retrolateral views.
491– 492
. Male chelicerae, frontal and lateral views.
493
. Cleared female genitalia, dorsal view. Scale lines: 0.2 mm.
PALPS. In general as in
M. pusillus
Huber
sp. nov.
; coxa with retrolateral apophysis, trochanter barely modified, femur proximally with large retrolateral-ventral process, dorsally with low hump, distally with ventral conical process; retrolateral trichobothrium on tibia very distal; procursus apparently indistinguishable from
M. pusillus
Huber
sp. nov.
(cf.
Figs 479–481
), at basis with dorsal process with obtuse tip, without retrolateral process, with pair of distal sclerites connected by transparent membrane; genital bulb (
Figs 488–490
) with large process partly membranous/whitish, with distinctive distal sclerite divided into two lobes.
LEGS. Without spines and curved hairs; few vertical hairs; coxa 4 unmodified; retrolateral trichobothrium of tibia 1 at 3%; prolateral trichobothrium present on all leg tibiae; tarsus 1 with ~35 pseudosegments, fairly distinct.
Female
In general similar to male but carapace posteriorly without median process, abdomen shorter. Tibia 1: 5.1. Epigynum (
Fig. 476
) simple rectangular plate, anteriorly straight, posteriorly weakly curved, pair of dark internal structures distinct in uncleared specimens; no posterior plate. Internal genitalia (
Figs 477– 478
,
493
) with large lateral ear-shaped structures, pore plates in lateral position.
Distribution
Known from
type
locality only, in
Venezuela
,
Falcón
(Fig. 1044).