Two new species of Eustigmaeus Berlese (Acari: Trombidiformes: Stigmaeidae) from Brazil, with a key to the American species
Author
Paktinat-Saeij, Saeid
Author
Bagheri, Mohammad
Author
De Castro, Tatiane M. M. G.
Author
De Moraes, Gilberto J.
text
Zootaxa
2016
4066
5
571
580
journal article
51165
10.11646/zootaxa.4066.5.5
eddb988d-489f-4cfa-b3fc-14004f0e474b
1175-5326
263977
E778225E-7276-4553-A932-80EC0C46C5F6
Eustigmaeus piracicabensis
Paktinat-Saeij & Bagheri
sp. nov.
(
Figs. 1–10
,
19, 21–22
)
Female
(n = 3): Length of idiosoma 292 (321–330); gnathosoma 102 (103–110); width of idiosoma 231 (253–268). Length of legs I–IV: 237 (241–245); 195 (196–197); 187 (183–192); 225 (225–238).
Dorsum of idiosoma
(
Figs. 1
,
19
). Covered by two shields, leaving exposed margin of unsclerotized cuticle around edges; shields ornamented with polygonal depressions, without vacuoles but with fine punctations (
Figs. 2
,
19
); without callosities between idiosomal shield and humeral shield. Prodorsal shield triangular and bearing four pairs of setae (
vi
,
ve
,
sci
and
sce
) and one pair of eyes between setae
ve
and
sci
. Humeral shields subtriangular, ornamented with depressions and bearing
c2
; hysterosomal shield with six pairs of setae (
c1
,
d1
,
d2
,
e1
,
e2
and
f1
); dorsal body setae (
Figs. 3
,
22
) inserted on protuberances, subequal, smooth and clavate with hyaline sheaths, except
h1
and
h2
setiform and distinctly shorter. Lengths of dorsal setae:
vi
63
(53–58);
ve
70 (70–73);
sci
60 (53– 58);
sce
62 (58–63);
c1
62 (54–58);
c2
33 (30–34);
d1
67 (65–66);
d2
69 (60–64);
e1
72
(68–70);
e2
62
(53–62);
f1
54 (47–52);
h1
22 (20–22);
h2
15 (11–14). Distances between dorsal setae:
vi–
vi
18 (17–18);
ve–ve
65 (65–67);
vi– ve
50 (53–55);
ve–sci
30 (26–28);
sci–sci
110 (106–109);
sce–sce
145 (142–150);
sci–sce
26 (22–25);
c1–c1
78 (72–75);
c1–d1
50 (51–55);
c1–c2
76 (85–96);
c1–d2
33 (30–36);
c2–c2
218 (244–247);
d1–d1
74 (72–77);
d1–d2
48 (52–53);
d1–
e1
58 (63–65);
d1–
e2
34 (32–33);
d2–d2
140 (136–141);
d2–
e2
60 (62–63);
e1–
e1
68 (65–70);
e1–
e2
40 (40–47);
e2–e2
115 (114–118);
e1–f1
43 (45–50);
f1–f1
67 (58–60);
h1–h1
33 (40–42);
h2–h2
42 (47–50);
h1–h2
8 (8).
Venter of idiosoma
(
Fig. 4
). Endopodal plates separated medially, reticulate and punctate, bearing three pairs of setae (
1a
,
3a
and
4a
). Anogenital area reticulate, but anal valves smooth; with three pairs of aggenital (
ag1–3
) and three pairs of pseudanal (
ps1–3
) setae. Suranal shield situated ventrally, pressed against anogenital shield, with depressions and punctate, bearing
h1
and
h2
, adjacent to posterior horseshoe-shaped shield ornamented by tiny depressions (
Fig. 5
). Measurements of setae:
1a
20 (17–18);
3a
22 (19–20);
4a
23 (20–21);
ag1
11 (11–12);
ag2
17 (14–17);
ag3
12 (13–14);
ps1
12 (11–12);
ps2
11 (9–10);
ps3
9 (7–9).
Gnathosoma
. Subcapitulum (
Fig. 6
) reticulate with fine punctations, bearing subcapitular setae
m
16 (15–16) and
n
17 (15–16) and adoral setae
or1
10 (11) and
or2
12 (11–12). Distance
m–m
20 (18–19) and
n–n
28 (28–30). Palpus 62 (64–68) long (
Fig. 6
), five segmented; palptrochanter without setae; palpfemur with three setae; palpgenu with two setae; palptibia with two tactile setae + one well-developed claw + one spine-like accessory claw; palptarsus with four tactile setae + one solenidion (ω), one subapical eupathidium and one distal trifid eupathidium.
Legs
(
Figs. 7–10
). Setation: coxae (excluding
1a
,
3a
and
4a
) 2-2-2-2, trochanters 1-1-1-1, femora 6-5-3-2, genua 3(+1κ)-3(+1κ)-1-1, tibiae 5(+1φ+1φρ)-5(+1φ)-5(+1φ)-5(+1φ),tarsi 13(+1ω)-9(+1ω)-7(+1ω)-7. Length of solenidia: ωI 19 (18–19); ωII 22 (20–23); ωIII 8 (8–9); φI 9 (11–12); φρI 24 (19–22); φII 18 (18–20); φIII 17 (16– 19). φIV 23 (21–22).
Immature stages and male:
Unknown.
Remarks
. The new species is distinguished from all other
Eustigmaeus
species by having the extra horseshoeshaped shield adjacent to the suranal shield. It resembles
Eustigmaeus collarti
(
Cooreman, 1955
)
and
E. distinctus
(
Wood, 1966
)
in having dorsal ornamentations, endopodal shields separated, and the same femora and genua chaetotaxy; however, it can be distinguished by 1) lacking the solenidion on tarsus IV (7+1ω in other species), 2) one seta on trochanter III (two in other species), 3) three pairs of aggenital setae (two pairs in other species), 4) endopodal shield reticulate (smooth in other species). Furthermore, the new species differs in the shape of dorsal setae from
E. collarti
.
FIGURES 1–6.
Eustigmaeus piracicabensis
Paktinat-Saeij & Bagheri
sp. nov.
(Female): 1. Dorsal view of idiosoma, 2. Dorsal dimples, 3. Dorsal setae, 4, 5. Ventral view of idiosoma, 6. Gnathosoma: Subcapitulum (Ventral view), Palp (Dorsal view).
FIGURES 7–10.
Eustigmaeus piracicabensis
Paktinat-Saeij & Bagheri
sp. nov.
(Female): 7. Leg I, 8. Leg II, 9. Leg III, 10. Leg IV.
Also,
E.
piracicabensis
sp. nov.
resembles
E. reticulatellus
(Habbeb,
1961
)
in having three pairs of aggenital setae, separate and reticulate endopodal shields, and the chaetotaxy of the femora, genua and tarsi; but it differs from the latter by having one seta on trochanter III instead of two, anogenital area reticulate instead of smooth, and setae
h
1
and
h
2
simple instead of clavate with hyaline tips.
Etymology.
The epithet
piracicabensis
refers to “from Piracicaba”, the
type
locality of the new species.
Type
material.
Holotype
female and two
paratype
females from soil and humus under rubber trees (
Hevea brasiliensis
Müell. Arg.
), collected on
March 28, 1999
at Piracicaba, state of São Paulo,
Brazil
by J.L. Mineiro. All
types
deposited at the mite reference collection of Departamento de Entomologia e Acarologia, ESALQ-USP, Piracicaba, São Paulo State,
Brazil
.