Redescriptions of North American Epidamaeus (Acari, Oribatida, Damaeidae) species proposed by N. Banks, H. E. Ewing, A. P. Jacot, and J. W. Wilson
Author
Norton, Roy A.
0000-0001-9051-1450
ranorton@esf.edu
Author
Ermilov, Sergey G.
0000-0001-9051-1450
ranorton@esf.edu
text
Zootaxa
2021
2021-08-16
5021
1
1
65
http://dx.doi.org/10.11646/zootaxa.5021.1.1
journal article
10.11646/zootaxa.5021.1.1
1175-5326
5225195
4B68BA80-1CB6-4766-9BDC-EE780CA15337
Epidamaeus olitor
(Jacot, 1937)
(
Figs 22–24
)
Belba olitor
Jacot, 1937a
(p. 355)
Epidamaeus olitor
(Jacot, 1937)
;
Marshall
et al
. (1987
, p. 142
)
Damaeus
(
Epidamaeus
)
olitor
(Jacot, 1937)
;
Subías (2004
, p. 79
)
Diagnosis
Epidamaeus
species
with total length of adult 398–448. Cerotegument mostly with thick layer of filamentous excrescences; exuvial scalps usually present on notogaster. Prodorsum without propodolateral apophysis; Tubercle
Ba
present,
Bp
absent. Bothridial seta smooth, long, flagellate, with thin, highly flexible distal third; seta
in
similar in form but about 2/3 as long. Notogaster with spina adnata usually of medium size, relatively straight, variously tapered; setae of
c
-,
l
- and
h
-series acicular, slightly arched, radially directed, usually smooth. Parastigmatic enantiophysis dimorphic, with
Sa
relatively large, horn-like,
Sp
much shorter, conical; ventrosejugal enantiophysis with only tubercle
Va
; enantiophyses
E2
,
M
absent; discidium absent. Seta
ad
3
well lateral to anal plate. Leg IV 1.1–1.2 times body length; femur IV shorter than trochanter IV (~1: 1.2).
Adult
Dimensions.
Total length and maximum width, including seven cotypes (n =
4 females
,
6 males
) 385–441 × 249– 265; males usually smaller (398–415) than females (415–441).
Integument
(
Fig. 23
). Body color yellowish to medium brown. Cerotegument with mostly filamentous excrescences, forming thick, loose mat on legs (except distal part of tarsi) and in sejugal region; with long, loose filaments on exposed parts of notogaster and sejugal region; shorter, loose filaments on venter. Filaments or shorter excrescences usually covering most leg setae and solenidia, as well as prodorsal setae and notogastral setae
p
1
–
p
3
; most other body setae usually with little or no cerotegument. Procuticle with general porosity but surface mostly smooth; microtubercles present locally: distinct on stalks of basal leg segments, moderately to weakly developed on anal plates, enantiophyses and other body tubercles. Usually with full stack of juvenile exuvial scalps, lacking adherent fecal pellets, eggshells, or other large debris (
Fig. 23A
).
Prodorsum
(
Figs 22A, B
,
23B, C
). Body wall anterior to acetabula I, II oblique, nearly flat in dorsal view; propodolateral apophysis absent; without strong contour anterior to bothridium. Postbothridial enantiophysis represented by well-developed, triangular tubercle
Ba
, usually with low ridge or strong contour in usual position of
Bp
;
Da
and laterosejugal enantiophysis absent. Sigillar patches of cheliceral and subcapitular muscles conspicuous in transmitted light (not illustrated). Setae
le
and
ro
similar in length (69–77) and thickness; finely attenuate, weakly barbed, curved anteromedially but with flexible tips. Seta
in
(118–156) long, subflagellate (
Fig. 23C
), fine, flexible tip often broken (
Fig. 23B
); with small barbs in proximal half; angled posterolaterad. Seta
ex
(49–53) thin, attenuate, weakly barbed, usually curved dorsad; vestige
exv
absent. Bothridium with external part funnel-shaped, with welldefined thickened vertical bands; mutual distance of pair twice that of tubercles
Ba
. Bothridial seta (159–228) usually smooth, flagellate, directed dorsolaterad, usually almost straight (
Fig. 23B
) except for fine, flexible tip; tip usually hidden in thick cerotegument but often broken.
Notogaster
(
Figs 22A–C
;
23A, D–H
). Nearly circular in outline, about 1.1 times longer than broad; uniformly curved, hemispherical with maximum height in middle. Spina adnata of medium length (usually 25–30 but up to 40), usually barely reaching level of prodorsal tubercle
Ba;
usually narrowly triangular, rarely thicker, curved (
Fig. 23E
); pair relatively widespread, mutual distance ~ 0.4 times maximum notogastral width. Setae of
c
-,
l
- and
h
-series directed radially, inserted in shallow curve, with mutual distance of lyrifissure
im
~ 1.7 times that of
lm
in dorsal view; pigmented (light grey to brown), acicular, slightly bowed (
Fig. 23H
), usually smooth or with inconspicuous, fine surface roughening (rarely with barbs proximally); usual length range (outliers in parentheses):
c
1
61–69 (83),
c
2
63–76 (83),
la
5 4–67 (78),
lm
51–66 (74),
lp
49–66 (74),
h
3
56–74,
h
2
(54–74),
h
1
47–56 (61). Setae of
p
-row slightly dimorphic:
p
1
projecting posterolaterad, subflagellate (82–90), barbed proximally;
p
2
,
p
3
curved laterad, attenuate, shorter (53–61) and slightly thinner, almost smooth. Seta
c
3
rarely, aberrantly developed at base of spina adnata (
Fig. 23G
; see R21).
Coxisternum and lateral podosoma
(
Figs 22B, D
,
23I
). Tectum of podocephalic fossa normally developed, without lateral tooth-like projection. Without medial coxisternal pit on epimere I. Enantiophyses
E2
,
M
absent; tubercle
Va
large, triangular;
Vp
absent, often a strong, ridge-like contour in its place. Tubercles of parastigmatic enantiophysis dimorphic:
Sa
horn-like, slightly bowed;
Sp
short, conical, directed toward
Sa
. Epimeral setae attenuate, weakly barbed, setation: 3–1–3–4; approximate lengths
1a
,
1c
,
2a
,
3a
(20);
1b
,
3b
,
4a
,
4b
(28–32);
3c
,
4c
,
4d
(41–45). Seta
3c
slightly removed from
Sp
and acetabulum III. Discidium absent.
Anogenital region
(
Fig. 22C, D
). Anal plate lacking longitudinal line or carina parallel to medial margin, such that usual narrow band not demarcated. Genital (anterior pair 24–28; others 20), aggenital (20–24), anal (36–45) and adanal (36–45) setae attenuate, weakly barbed. Adanal seta
ad
3
well removed from anal aperture, with
ad
1
–
ad
3
forming oblique row directed toward acetabulum IV. Lyrifissure
iad
oriented diagonally, slightly removed from anal aperture;
ian
present, but minute, anterior to seta
an
2
.
Gnathosoma
. Subcapitulum longer than wide (100–105 × 69–77). Subcapitular setae (
a
, 20;
m
,
h
, 28–32) attenuate, weakly barbed. Adoral setae (10) attenuate, thin, weakly barbed. Palps (82–86) with normal setation: 0– 2–1–3–9(+ω). Solenidion bacilliform, appressed to tarsal surface. Postpalpal seta (6) spiniform, smooth. Chelicera (92–102) typical of family; attenuate seta
cha
(28) barbed throughout,
chb
(20) barbed unilaterally in middle part.
Legs
(
Fig. 23A
,
24
). Relative lengths (I to IV) 1.0: 0.8: 1.0: 1.2; leg IV 1.1–1.2 times body length. Femur IV shorter than trochanter IV (~1:1.2); approximate length of leg segments shown in
Table 1
. Proximal stalk of femur IV shorter than distal bulb (~1:1.2–1.6). Claw of each leg smooth, basal tooth absent. Formulas of leg setation and solenidia: I (1–7–4–4–20) [1–2–2], II (1–6–4–4–17) [1–1–2], III (2–4–3–3–17) [1–1–0], IV (1–4–3–3–14) [0–1–0]. Notably: all tarsi with proximal accessory pair (
v
) present,
v
2
ʹ
and
v
2
ʺ
absent;
v
2
ʺ
present on femur I, absent from II; seta
vʺ
absent from femur III. Setae
d
and
l
similar to other setae (thin, attenuate); seta
d
of genua I–III ~1.5–2.5 times longer than respective coupled solenidia. Solenidion φ
1
on tibia I and φ on tibia IV both flagellate (‘tactile’); other solenidia thin, blunt, isodiametric or slightly tapered (‘ceratiform’), curved to various degrees. Famulus of tarsus I acicular to acuminate, erect. Shapes and relative sizes of other setae shown in
Fig. 20
.
FIGURE 22.
Epidamaeus olitor
(Jacot 1937)
, adult: A—dorsal view (legs not shown except trochanters I; strong curvature of seta
bs
is artifact of mounting, cf. Fig. 23 B); B—anterior half of body, right lateral view (gnathosoma and legs not shown); C—posterior part of body, right lateral view; D—ventral view (legs represented only by trochanters). Scale bar 100 μm.
FIGURE 23.
Epidamaeus olitor
(Jacot 1937)
, light photographs of adult: A—lateral habitus of specimen from New York;
B—posterior prodorsum and anterior notogaster of cotype, dorsolateral view (seta
in
broken; left insert = enlarged tip of seta
bs
;
upper right insert = same of different cotype); C—partial prodorsum of crushed slide-mounted specimen from
New Hampshire
(anterior to left) showing dislodged but intact seta
in
(arrow on tip; * = dislodged notogastral seta); D—right tubercle
Ba
and spina adnata from cotype; E—unusual left spina adnata from
New York
specimen; F—typical left spina adnata from
New York
specimen; G—right spina adnata from
New York
specimen with seta
c
3
aberrantly expressed; H—notogastral seta
c
2
of cotype; I—left ventrosejugal region of cotype, ventral view. Scale bars 10 μm (D–I), 20 μm (B, C), 100 μm (A).
FIGURE 24.
Epidamaeus olitor
(Jacot 1937)
, adult: A—right leg I, except trochanter, abaxial view; B—femur, genu and tibia of right leg II, dorsoabaxial view; C—femur, genu and tibia of left leg III, abaxial view; D—left leg IV, except trochanter, abaxial view. Scale bar 50 μm.
Juveniles
Unknown, except for exuvial scalps on adult notogaster (
Fig. 23A
). Scalps always appear compressed and damaged. Attachment cornicle
k
observable in only
one specimen
(instar not determinable): in form of spiral, similar to that of
Metabelba papillipes
(Nicolet, 1855)
or
Porobelba spinosa
(Sellnick 1920)
(
Ermilov 2012
; his
Figs 2.9
,
3.8
).