Notes on
two species of the genus Atemnus Canestrini (Pseudoscorpiones:
Atemnidae) from China
Jun-fang Hu 1 & Feng Zhang2
1,2 College of Life Sciences, Hebei University, Baoding, Hebei 071002
China
Email: 1 jfanghu@gmail.com, 2 dudu06042001@163.com
(corresponding author)
Date of publication
(online): 26 September 2012
Date of publication (print):
26 September 2012
ISSN 0974-7907 (online) |
0974-7893 (print)
Editor: Volker
Mahnert
Manuscript details:
Ms # o3049
Received 26 December 2011
Final received 12 August
2012
Finally accepted 27 August
2012
Citation: Hu, J-f.& F. Zhang (2012). Notes on two
species of the genus Atemnus Canestrini (Pseudoscorpiones: Atemnidae)
from China. Journal of Threatened Taxa 4(11):
3059–3066.
Copyright: ©
Jun-fang Hu & Feng Zhang 2012. Creative Commons
Attribution 3.0 Unported License. JoTT allows unrestricted use of this
article in any medium for non-profit purposes, reproduction and distribution by
providing adequate credit to the authors and the source of publication.
Acknowledgements: We are
grateful to Prof. Mark S. Harvey
(Western Australian Museum, Perth, Australia) and Prof. Volker Mahnert (Museum
of Natural History, Geneva, Switzerland) for their invaluable comments and many
helps on this text. Many thanks are given to Prof. Xin-ping Wang
for his generous helps to improve the grammar in this text. This
work was supported by the National Natural Science Foundation of China(Nos. 30970325, 31071885, 31093430).
Abstract: Two pseudoscorpion species of the
genus Atemnus Canestrini, 1884 are reported from China: A. limuensis sp. nov. fromthe Ormosia tree bark in a humid tropical forest and A. politus Simon, 1878 from leaf litter in a temperate deciduous forest. A key to all
known species of this genus is provided.
Keywords: Atemnus, China, new
species, pseudoscorpions, taxonomy.
Abbreviations: Trichobothria: b = basal;sb = sub-basal; st = sub-terminal; t =
terminal; ib = interior basal; isb =
interior sub-basal; ist = interior sub-terminal; it =
interior terminal; eb = exterior basal; esb =
exterior sub-basal; est = exterior sub-terminal; et =
exterior terminal. Male genitalia: a = lateral apodeme; b = hooked branch; c =
sclerotized bar; d = longitudinal fold of medial diverticulum; e = ejaculatory
canal atrium; f = lateral rods; g = dorsal apodeme; h = ventral diverticulum; l
= lateral lip of lateral apodeme.
For
figures, images, tables -- click here
The
pseudoscorpion family Atemnidae Kishida, 1929 (see Judson 2010) is divided into
two subfamilies and 19 genera, with four species and four genera from China (AtemnusCanestrini, 1884, Anatemnus Beier, 1932 and Paratemnoides Harvey,
1991 of the subfamily Atemninae Kishida, 1929 and DiplotemnusChamberlin, 1933 of the subfamily Miratemninae Beier, 1932). Atemnus Canestrini, 1884 is the type
genus of Atemnidae and includes five species: Atemnus letourneuxi(Simon, 1881) from northern Africa and Yemen, A. neotropicusHoff, 1946 from the Carribean region, A. strinatii Beier, 1977
from the Philippines, A. syriacus (Beier, 1955) from Europe and
the Middle East, and A. politus (Simon, 1878) widely distributed
from Europe and northern Africa to Asia, including China (Harvey 2011).
With support
from the National Natural Science Foundation of China, the authors began to
collect and study Chinese pseudoscorpions in 2007. Two Atemnus species have been
found in our collection, including a new Atemnus species from
Hainan, which differs morphologically from other Atemnus species in
China and A. politus from Shanxi Province. In this paper, we describe the new
species and provide a detailed description of A. politus based on
the material from Shanxi, China.
Materials
and Methods
The material was preserved in 75% alcohol. The description and terminology follow
Chamberlin (1931) and Judson (2007). Terminology of genitalia
follows Klausen (2005). All
measurements are given in millimetres. Drawings were made with the aid of a prism mounted above the eyepiece of
a compound microscope. Photographs
were taken with a Leica M165c stereomicroscope. Detailed
examination was carried out with a Nikon YS100 general optical microscope. Temporary slide mounts were made in
glycerol. The specimens referred
here are deposited in the Museum of Hebei University (MHBU), Baoding City,
China.
Results
Genus Atemnus Canestrini, 1884
For synonymies see Harvey (2011).
Type
species: Atemnus
politus (Simon, 1878).
Diagnosis:See (Beier 1932a,b;
Murthy & Ananthakrishnan 1977).
Remarks: Atemnus, the type genus of
Atemnidae, is similar to Anatemnus in having a similar pedipalpal
patella, but can be distinguished by the trichobothrial pattern on the fixed
finger: the distance between est and esb is the same as that
between ist and isb in Atemnus, but longer in Anatemnus. The definition of atemnid genera has
long been based on external characters only. Klausen (2005) studied the male
genitalia of 44 Atemninae and Miratemninae species and concluded that the
present generic delimitation was not reliable. As a result, the male genital structures
are also explored, in addition to the external characters. The major
differences between the two genera Atemnus and Anatemnus can also
be found in the male genital organ (Klausen 2005, p.658, figs 9, 23–25).
Atemnus politus (Simon, 1878)
(Image 1, Fig. 1)
For synonymies see Harvey (2011).
Material
examined: 02.viii.2010,
five males (Ps.-MHBU-SX10080201–10080205) and five females
(Ps.-MHBU-SX10080206–10080210) from China, Shanxi Province, Licheng City,
Huangyadong Forest Park (36.800N & 113.450E), 757m,
coll. Sheng-tao Guo leg.
Diagnosis:Atemnus politus is characterized by the
granulatemedial face of the
pedipalpal femur and patella,the presence of a round dorsal tubercle on the trochanter, and the relatively
small size of chela with pedicel (male 1.15–1.33 mm, female
1.30–1.35 mm).
Description:Pedipalps and the
anterior half of carapace deep brown, tergites yellow (Image 1). Setae on body and legs apically dentate.
Carapace
smooth (Fig. 1A), without furrow and longer than broad (1.12 × in male
and 1.04–1.07 × in female); with distinct eyespots; 38–42
setae in total, of which 6 on anterior margin and 6–8 on posterior
margin; the anterior half darker than the posterior half.
Abdomen
tergites IV–X incompletely divided, half-tergites with 4–6 marginal
setae. Tergal chaetotaxy: 6–8 : 6–8 : 8 :
10–12 : 10–11 : 10–11 : 11–12 : 12 : 12 : 10–12
(4T) : 8 (2T) : 2; sternites IV–VIII divided, half-sternites with
5–8 setae, sternal chaetotaxy (IV–XI) : 9–11 : 11–14 :
12–13 : 12–14 : 12–14 : 12–15 : 10–12 (4T) :
8–10 (4T) : 2. Anterior
genital operculum of male (Fig. 1J) with 9–10 setae on each side and 10
on posterior margin; that of female (Fig. 1H) with 10–12 setae on
anterior genital operculum and 2–3 lyrifissures, and with 9–10
setae on posterior margin. Male
genital structure (Fig. 1K): the distal part (l) of lateral apodemes is
relatively smaller, and the hooked branch (b) is bowed distally and terminates
in a plate-like tip, the proximal part has a distinct dark sclerotized bar (c);
the longitudinal fold of medial diverticula (d) has a projection midway along its
length; the ejaculatory canal atrium (e) not well-developed; the lateral rods
(f) long and diverging proximally; the tip of dorsal apodeme (g) completely
joined; the ventral diverticulum (h) bilobed. Female genital structure (Fig. 1D)
simple, spermathecae provided with separated median cribriform plates.
Cheliceral
hand with four setae, bs and es short and finely dentate, and isand ls long and acute, fixed finger with four retrorse teeth and three
small apical teeth, movable finger with a long, tooth-like subapical lobe, male
galea (Fig. 1B) relatively short and with six branchelets and female galea (Fig.
1C) long and with 5–6 distinct branchelets, of which the basal one
rebranched, serrula exterior 21–25 lamellae, rallum of four setae, only
the distal one dentate anteriorly.
Pedipalp:
trochanter 1.72–1.74, femur 2.50–2.67, patella 2.19–2.23,
chela with pedicel 3.03–3.09, chela without pedicel 2.82–2.91, hand
without pedicel 1.68–1.70 × longer than broad, and movable finger
0.59–0.71 × longer than hand (female trochanter 1.43–1.50,
femur 2.67–2.86, patella 1.97–2.09, chela with pedicel
2.70–2.77, chela without pedicel 2.46–2.55, hand without pedicel
1.50–1.55 × longer than broad, and movable finger 0.75–0.77
× longer than hand). The
prolateral face of pedipalpal femur and patella strongly granulate
(Figs. 1E–F); trochanter with distinct round dorsal protuberance,
fixed finger (Fig. 1G) with 29–30 cusped marginal teeth, movable finger with
35 marginal teeth, venom duct short, ramosus nodus between trichobothria etand it, but near et. Trichobothrial pattern: st on movable finger nearly between tthan sb; on fixed finger distance of est removed from esbsame as ist and isb, it from finger tip nearly equals to
distance between ist and isb.
Legs fairly
stout, without granular, claws simple and longer than arolia, subterminal seta
acute and curved. Tactile seta on
tarsus IV (Fig. 2I) situated near the base (TS = 0.12).
Dimensions
(length/breadth or depth, in mm): Male. Body length:
2.55–2.61. Carapace 0.75–0.84 / 0.67–0.75 (1.12); pedipalp:
trochanter 0.40–0.43 / 0.23–0.25 (1.72–1.74), femur
0.70–0.80 / 0.28–0.30 (2.50–2.67), patella 0.70–0.78 /
0.32–0.35 (2.19–2.23), chela with pedicel 1.15–1.33 /
0.38–0.43 (3.03–3.09), chela without pedicel 1.07–1.25
(2.82–2.91), hand without pedicel 0.64–0.73 (1.68–1.70),
movable finger length 0.43–0.52 (0.59–0.71 × hand); leg I:
femur 0.23–0.25 / 0.15–0.18 (1.39–1.53), patella
0.38–0.40 / 0.14 – 0.18 (2.22–2.71), tibia 0.40 /
0.10–0.11 (3.64–4.00), tarsus 0.38 – 0.40 / 0.08–0.10
(4.00–4.75); leg IV: femur + patella 0.70–0.80 / 0.23–0.25
(3.04–3.20), tibia 0.53–0.60 / 0.15–0.18 (3.33–3.53),
tarsus 0.40–0.43 / 0.10–0.12 (3.58–4.00).
Female. Body
length: 3.38–3.47. Carapace 0.80 / 0.75–0.77 (1.04–1.07);
pedipalp: trochanter 0.42– 0.43 / 0.28–0.30 (1.43–1.50),
femur 0.80 / 0.28–0.30 (2.67–2.86), patella 0.73–0.75 /
0.35–0.38 (1.97–2.09), chela with pedicel 1.30–1.35 /
0.47–0.50 (2.70–2.77), chela without pedicel 1.20–1.23
(2.46–2.55), hand without pedicel 0.73–0.75 (1.50–1.55),
movable finger length 0.55–0.58 (0.75–0.77 × hand); leg I:
femur 0.28–0.35 / 0.15–0.18 (1.87–1.94), patella
0.38–0.40 / 0.15–0.18 (2.22–2.53), tibia 0.38–0.43 /
0.10–0.13 (3.31–3.80), tarsus 0.33–0.40 / 0.08–0.10
(4.00–4.13); leg IV: femur + patella 0.73–0.80 / 0.23–0.25
(3.17–3.20), tibia 0.55–0.60 / 0.15–0.18 (3.33–3.67),
tarsus 0.43–0.45 / 0.10–0.12 (3.75–4.30).
Distribution:China (Shanxi).
Habitat: The specimens of A. politus were
collected from leaf litter in a temperate deciduous forest.
Remarks: Atemnus politus was first reported from China by Beier
(1967). The male genital structures
of the specimens from Shanxi Province fit A. politus illustrated by
Klausen (2005). In addition, the
dimensions and proportions are rather consistent with those of A. politusgiven by Beier (1932a, b; 1963) and Dashdamirov & Schawaller (1992). Based on the external morphological
characters and male genital characters, we believe the material from Shanxi,
China belonging to A. politus.
Atemnus limuensis sp. nov.
(Image 2, Fig. 2)
Type
material: 07.v.2011,
holotype male (Ps.-MHBU-HN11050701) from China, Hainan Province, Mt. Limu
(19.170N & 109.740E), together with five males
(Ps.-MHBU-HN11050702– 11050706), nine females (Ps.-MHBU-HN11050707–
11050716) paratypes, coll. Junfang Hu leg.
Etymology:The specific name is
derived from the type locality.
Diagnosis: This new species can be recognized by the following
combination of characters: carapace with two distinct eyespots; body in large
size (male 4.38–4.88, female 5.40–6.25); retrolateral face of
pedipalpal trochanter, prolateral face of pedipalpal femur and patella, and
basal fingers distinctly granulate;dorsal and retrolateral face of trochanter with coniform tubercles; carapace
covered with numerous setae.
Description:Pedipalps and the
anterior half of carapace reddish-brown (Image 2), tergites brown. Setae on body and legs apically dentate.
Carapace
smooth, without furrow, longer than broad (1.16–1.20 × in male and
1.20–1.32 × in female); with distinct eyespots (Fig. 2A);
68–72 setae, with four on anterior margin and 8–10 on posterior
margin; the anterior half darker than the posterior half.
Abdomen all
tergites incompletely divided, half-tergites with 4–9 marginal setae.
Tergal chaetotaxy: 8–11 : 8–11 :
9–11 : 12–16 : 14–18 : 16–17 : 16–17 :
16–17 : 16–17 : 14–17 (4T) : 11–13 (4T) : 2; sternites
divided, half-sternites with 6–10 setae, sternal chaetotaxy (IV –
XI) : 16–17 : 18–19 : 17–18 : 17–18 : 18–20 :
16–19 : 12–18 (4T) : 13 (4T) : 2. Anterior genital operculum of
male (Fig. 2G) with 8–9 setae on each side and 10–11 on posterior
margin; that of female (Fig. 2J) with 8–10 setae on anterior genital
operculum and 8–10 setae on posterior margin. Male genital structure (Fig. 2K): the
hooked branch (b) bowed distally, terminated in a relatively small plate-like
tip, with a distinct dark sclerotized bar proximally (c); the longitudinal
folder of medial diverticula (d) with a projection medially and a prominent
extension along the sagittal plane, forming M-shape bulge (k); the ejaculatory
canal atrium (e) crescent-shaped on both sides and the distal end of the atrium
procurved; the lateral rods (f) long and diverging proximally; the tip of
dorsal apodeme (g) completely joined; the ventral diverticulum (h)
bilobed. Female genital structure
(Fig. 2I) simple, spermathecae with separated median cribriform plate.
Cheliceral
hand with four setae (Fig. 2B), bs and es short and finely
dentated, is and ls long and acute, fixed finger with four retrorse
teeth and 2–3 small apical teeth, movable finger with a long, tooth-like
subapical lobe, male galea (Fig. 2C) relatively short, with 6–7 branchelets,
female galea (Fig. 2D) long, with 5–6 distinct branchelets, of which the
basal one rebranched, serrula exterior 27–28 lamellae, rallum (Fig. 2E)
of 4 setae, only the distal one dentated anteriorly.
Pedipalp:
trochanter 1.10–1.30, femur 2.22–2.55, patella 2.12–2.18,
chela with pedicel 2.97–3.10, chela without pedicel 2.73–2.84, hand
without pedicel 1.71–1.72 longer than broad, and movable finger
0.59–0.63 × longer than hand (female trochanter 1.43–1.50, femur
2.27–2.38, patella 1.92–2.02, chela with pedicel 2.77–2.92,
chela without pedicel 2.49–2.58, hand without pedicel 1.58–1.67
longer than broad, and movable finger 0.63 × longer than hand). The
retrolateral face of pedipalpal trochanter (Fig. 2L), prolateral face of pedipalpal
femur and patella, and the basal fingers strongly granulated; trochanter with distinct coniform and
granulated protuberances, fixed finger (Fig. 2H) with 29–30 cusped marginal
teeth, movable finger with 35–36 marginal teeth, venom duct short, ramosus
nodus medially between trichobothria et and it. Trichobothrial
pattern: st on movable finger between t than sb; on fixed
finger est at the level of ist, distance
of est and esb same as ist and isb, it from
finger tip nearly equals to distance between ist and isb.
Legs fairly
stout and smooth, claws simple, longer than arolia, subterminal seta acute and
curved. Tactile seta on tarsus IV (Fig. 2F) situated proximally (TS = 0.20).
Dimensions
(length/breadth or depth, in mm): Male: Body length:
4.38–4.88. Carapace 1.10–1.20 / 0.95–1.00 (1.16–1.20);
pedipalp: trochanter 0.50–0.65 / 0.45–0.50 (1.10–1.30), femur
1.00–1.20 / 0.45–0.47 (2.22–2.55), patella 1.10–1.20 /
0.52–0.55 (2.12–2.18), chela with pedicel 1.80–1.90 /
0.58–0.64 (2.97–3.10), chela without pedicel 1.65–1.75
(2.73–2.84), hand without pedicel 1.00–1.10 (1.71–1.72),
movable finger length 0.63–0.65 (0.59–0.63 × hand); leg I:
femur 0.33–0.35 / 0.25–0.27 (1.30–1.32), patella
0.58–0.60 / 0.23–0.25 (2.40–2.52), tibia 0.50–0.55 /
0.15–0.17 (3.24–3.33), tarsus 0.38 – 0.45 / 0.12–0.14
(3.17–3.21); leg IV: femur + patella 1.05–1.15 / 0.38–0.40
(2.76–2.88), tibia 0.75–0.80 / 0.22–0.25 (3.20–3.41),
tarsus 0.50 – 0.55 / 0.14–0.15 (3.57–3.67).
Female: Body
length: 5.40–6.20. Carapace
1.20–1.25 / 0.95–1.00 (1.25–1.26); pedipalp: trochanter
0.50–0.60 / 0.35–0.40 (1.43–1.50), femur 0.95–1.00 /
0.40–0.44 (2.27–2.38), patella 0.95–1.00 / 0.47–0.52
(1.92–2.02), chela with pedicel 1.75–1.80 / 0.60–0.65
(2.77–2.92), chela without pedicel 1.55–1.62 (2.49–2.58),
hand without pedicel 1.00–1.03 (1.58–1.67), movable finger length
0.63–0.65 (0.63 × hand); leg I: femur 0.30–0.32 /
0.25–0.26 (1.20–1.23), patella 0.55–0.57 / 0.23–0.25
(2.28–2.39), tibia 0.50–0.55 / 0.15–0.18 (3.06–3.33),
tarsus 0.42–0.45 / 0.10–0.12 (3.75–4.20); leg IV: femur +
patella 1.05–1.10 / 0.40–0.45 (2.44–2.63), tibia
0.65–0.70 / 0.21–0.25 (2.80–3.10), tarsus 0.50–0.55 /
0.13–0.15 (3.67–3.85).
Distribution:China (Hainan Island).
Habitat: Atemnus limuensis sp. nov. was collected from under an Ormosia tree bark in a
humid tropical forest.
Remarks: Atemnus limuensis sp. nov. differs from A. letourneuxi in its large size and the
presence of strong granules on the prolateral face of the chelal patella. Atemnus neotropicus from Puerto
Rico is known only from a female, which differs from females of A.
limuensis sp. nov. inhaving a small size (body length 4.10mm), light in color, the presence of weak
eyespots and rounded dorsal protuberances on the chelal trochanter. Atemnus strinatii can be
distinguished from A. limuensis sp. nov. in having round dorsal tubercles on the chelal trochanter,
without eyespots and with weakly granulate chelal femur and patella. Atemnus
limuensis sp. nov. differsfrom A. syriacus by the slender pedipalp (male femur 2.22–2.55
×, patella 2.12–2.18 ×, chela with pedicel 2.97–3.10
×, chela without pedicel 2.73–2.84 ×, hand without pedicel
1.71–1.72 × versus femur 2.1 ×, patella 1.7 ×, chela
with pedicel 2.6 ×, chela without pedicel 2.3 × as long as broad inA. syriacus) and the absence of a brown band on carapace.
Atemnus
politus can be easily be separated from A. limuensis sp. nov. by the slimmer male genital organ (Figs. 1K, 2K): the
ejaculatory canal atrium (e) is not well-developed and may be aberrant in A.
politus; but in A. limuensis sp. nov., the atrium is normal,
crescent-shaped on either side, and the distal end of the atrium is typically
procurved. Moreover, the distal
part (l) of lateral apodemes (a) in A. limuensis sp. nov.is larger than that in A. politus. However, they have many congeneric
characters in the male genitalia (the letters refer to those of Figs. 1K and
2K): (1) the sclerotized distal part of lateral apodemes; (2) the presence of a
hooked branch on proximal part of the lateral apodemes; (3) the presence of a
rugose darker area on proximal part of the lateral apodemes; (4) the presence
of a round projection on medial diverticulum and a prominent extension along
the sagittal plane in M-shaped bulge (k) on two medial diverticula; (5) the
long and proximally diverging lateral rods; (6) the distally joined long dorsal
apodeme; and (7) the presence of bilobed anterior wall on the ventral
diverticulum.
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