Three new species of Pergalumna (Acari: Oribatida: Galumnidae) from the tropical rainforest of Veracruz, Mexico
Author
Palacios-Vargas, José G.
Author
Villagomez, Fernando
text
Zootaxa
2017
4242
1
77
94
journal article
36317
10.11646/zootaxa.4242.1.4
b8e77d1d-c517-4d04-8670-008d1d314366
1175-5326
376008
31C1F811-5A1A-486E-9993-73FB307B4C90
Pergalumna dactylaris
sp. nov.
(
Figs. 41
–60)
Diagnosis.
Bothridial setae setiform, apically barbed; integument densely striated in most of the body, generally with vertical orientation, some striations can be horizontals joining two vertical lines;
A2
absent; notogaster with ten pairs of alveoli; dorsosejugal suture fully developed; lyrifissure
iad
situated near anal plate; without porose area postanalis and medial pore.
Description.
(N=10) Length of males 867–936 (916), width 709–769 (740); length of females 818–966 (877), width 719–789 (750), height of both sexes 734. Color black to dark brown, with a light lenticular yellow region in prodorsum basis and anterior part of notogaster.
Prodorsum
(
Figs. 41
, 43, 44, 56). Slightly granulated surface in anterior region, near dorsosejugal suture this ornamentation disappears and begins an irregular striation; dorsosejugal suture separates a very large bright yellow lenticular region and continues towards anterior part of notogaster; lines
L
and
S
present, sclerotized;
Ad
apparently absent. Prodorsal setae (
Fig. 45
) present,
in
short, smooth and setiform (32),
le
long and barbed (114),
ro
similar in size to
le
, but a little smaller (98), inserted on the edge of ventral plate, barbed. With a cuticular depression anterior to insertion of
le
, rostrum with blunt apex.
Bothridial setae (
Figs. 45
, 60) setiform, long and thin (126), barbed apically, no “S” form insertion in bothridium. Chelicera (Fig. 46) normal shape (L=290, W=109), ornamented with punctuations from anterior to middle region,
cha
(81) and
chb
(52) barbed.
Notogaster
(
Figs. 41
,
54
). Integument completely striated (Fig. 59), ten pairs of alveoli,
lx
present; porose area
A2
absent, all others similar in size and form; without medial pore.
Porose area
Aa
(L=32, W=20) and
A1
(L=37, W=17) oval to round,
A3
(L=20, W=17) oval. Notogastric lyrifissures and setae in the same position as
Pergalumna hypergranulosa
sp. nov.
except lyrifissures
ih
and
ips
located laterally anterior to
A1
, opisthosomal glands
(gla)
well developed and slightly protuberant.
Pteromorph bilobed (Figs. 49, 57) (L=425, W=205 with convex anterior region,
220 in
middle and
235 in
distal), integument granulated, striated with ornamentation from basis to center, with additional irregular and linear sclerotized ornamentations, with a central notch; lyrifissure
ia
thick below the notch;
c
in habitual position.
Ventral plate
(Figs. 42, 55). Integument densely striated on whole plate. Subcapitulum (Fig. 47) (L=164, W=178) slightly granulated and ornamented,
h
long (25); epimeral setae of two sizes,
1b
(17) short,
3a
,
4a
and
3b
(27) longer; aggenital setae short (20), three pairs of adanal setae short (15) with
ad3
slightly separated; lyrifissure
iad
near anal plate; porose area postanalis absent (Fig. 48); genital plates (L=115, W=121) slightly striated, with four faint longitudinal lines (Fig. 58), with six short genital setae (15) inserted in 2–4; anal plates (L=164, W=175) completely striated, with two pairs of short anal setae (15).
Lateral region
(Figs. 44, 57). Lamellar (
L
) and sublamellar (
S
) lines present and well sclerotized, arched and parallel, sublamellar line S irregular; circumpedal line thick and sclerotized, slightly protuberant; rostrum with blunt apex.
FIGURES 41
‾
44.
Pergalumna dactylaris
sp. nov.
41. Notogaster, dorsal view; 42. Ventral plate; 43. Prodorsum; 44. Lateral region, pteromorph and legs ommited. Scale bars 50 µm.
Legs.
All heterotridactylous. Leg setation and solenidia from leg I–IV (solenidium in parenthesis). Femora 4- 4-2-2; genua 3(1)-3(1)-1(1)-2; tibiae 4(2)-4(1)-3(1)-3(1); tarsi 20(2)-15(2)-15-12.
Leg I (
Fig. 50
). Femora L=77, W=30; genua L=38, W=13; tibiae L=87, W=52; tarsi L=159, W=37. Solenidium σ (155) anterior, dorsal; solenidium
φ1
(242) very long,
φ2
(81) posterior, both dorsally inserted,
ω1
(77) shorter than
ω2
(112); famulus
å
very short (5), with blunt apex,
ft´´
setae is situated posteriorly. Leg II (Fig. 51). Femora L=193, W=84; genua L=74, W=32; tibiae L=81, W=44; tarsi L=114, W=37. Solenidium σ (163) dorsal and distal,
φ
(176) dorsal.
ω1
and
ω2
identical (54), blunt apex,
ft´
anterior to
ω1
. Leg III (
Fig. 52
). Femora L=133, W=91; genua L=37, W=27, tibiae L=121, W=42; tarsi L=136, W=35. Solenidium σ (57) rigid,
φ
(151) dorsal, at the height of
l´
. Leg IV (Fig. 53). Femora L=172, W=84; genua L=74, W=25, tibiae L=131, W=37; tarsi L=160, W=30. Solenidium
φ
(131) in middle region of the tibia, without cuticular fold.
FIGURES 45
‾
49.
Pergalumna dactylaris
sp. nov.
45. Prodorsal setae; 46. Right chelicera, paraxial view; 47. Subcapitulum, ventral view; 48. Posterior region; 49. Right pteromorph. Scale bars 50 µm.
Type
material.
Holotype
(male) mounted on slide.
08/IV/2014
,
Mexico
,
Veracruz
,
Estación de Biología Tropical
,
Los Tuxtlas
, sample of soil and litter,
L. Villagomez
,
L. A. Martínez
y
A. D. Ruiz
cols.
18°35’02.04’’ N
,
95°04’39.54’’ W
.
242 m
a.s.l.
Four
paratypes
on slide with same data except
18/IV/2014
(
1♀
and
3♂
), four
paratypes
on slide with date
09/VI/2014
.
F. Villagomez
col. (
1♀
and
3♂
)
.
Fifteen more
paratypes
from the same locality and same data deposited in 96% ethanol.
This
material is deposited in the collection of Collembola de
México
y Ácaros Edáficos of
Laboratorio de Ecología
y
Sistemática de Microartrópodos
(
LESM
),
Facultad de Ciencias
, UNAM.
Etymology.
The specific name “
dactylaris
” describes the similarity of the integumentary ornamentation with human fingerprints.
Remarks.
The ornamentation on the prodorsum and notogaster of
P. dactylaris
sp. nov.
resembles
Pergalumna striata
(
Pérez-Íñigo & Baggio, 1980
)
, from
Brazil
, but can be distinguished by the presence of only three notogastric porosea areas instead of four, and being almost twice as long as in
P. striata
(400–440). The shape of bothridial setae
bs
is similar to
Pergalumna decorata
Balogh & Mahunka, 1977
(
Bolivia
)
, which has
Aa
closer to
lm
than
la
, whereas in
P. dactylaris
sp. nov.
Aa
is located exactly in the middle between them; besides interlamellar setae
in
are short, but not minute, and the Bolivian species is much smaller (L=637–653, W=469– 494) than the Mexican (L=838–986, W=720–789). New species is also similar to
Pergalumna decoratissima
Pérez-Íñigo & Baggio, 1986
(
Ecuador
)
which has a granulated prodorsum and the rest of the body ornamented with longitudinal striae or grooves, however, lamellar setae (
le
) in this species is more than twice as long as rostral setae (
ro
), and the anal and genital plates are ornamented in the same manner, while in
P. dactylaris
sp. nov.
prodorsal setae
le
and
ro
are subequal in size, also genital and anal plates are ornamented with different patterns, with less ornamentations on genital plate. Finally
Pergalumna paradecoratissima
Ermilov & Kalúz, 2012
(
Ecuador
)
differs by having a tooth-shaped projection on each side of prodorsum, anal plate smooth and the presence of one small and oval porose area postanalis. In addition,
P. dactylaris
sp. nov.
seems to be the only species with a clear and well delimitated lenticular region between prodorsum and the base of notogaster.
Sympatric speciation.
The three species come from Los Tuxtlas,
Veracruz
, and as they live in the same locality and biotope, it seems that a sympatric speciation has occurred. We have analyzed the chelicerae, but we have not found any important difference, but we think that each of them is using a new niche, which had reduced gene flow with individuals exploiting another niche. Unpublished data support this, Villagomez (2015) performed techniques of extraction and amplification of ribosomal 18S rRNA and mitochondrial Cytochrome Oxidase c 1 (Cox 1) for molecular characterization of these species and to delimit the relationship between genetic distance and morphological characters. The results show that genetic distance between species with molecular marker Cox 1 observed in the three species varies from 0.3, 2.46 or 6.02%.