Two new species of Pogonognathellus (Collembola: Tomoceridae) from China, with a discussion of East Asian species
Author
Wang, Tianle
Author
Yu, Daoyuan
Author
Zhang, Feng
text
Journal of Natural History
2013
J. Nat. Hist.
2013-03-18
47
17 - 18
1243
1255
http://dx.doi.org/10.1080/00222933.2012.752541
journal article
6415
10.1080/00222933.2012.752541
b5131b8c-8bc5-4806-9555-ba440502605b
1464-5262
4631135
Pogonognathellus heterochros
sp. nov.
(
Figures 1A
,
2–4
)
Description
Body length.
Up to
6.9 mm
.
Body colour.
Scales brown. Ground colour white. Ant. III, head, Th. II, base of front and mid legs dark purple. Pigment on Ant. III darker at the base and gradually lighter towards tip. Eye patches black. Unpigmented spots on Th. II forming an irregular but relatively stable pattern. Anterior part of Th. III and femora of hind legs with diffuse purple pigment (
Figure 1A
).
Head.
Antennae about 0.75 times body length, antennal length ratio as I: II: III + IV = 1.0: 1.4: 7.1–10.0, Ant. I, II and base of Ant. III scaled. Ommatidia 6 + 6. Labral setae four
/
five, five, four, all smooth, four setae of the third row thicker than others, labral margin with four spiny papillae, medial two curved and thinner, lateral two straight and stronger (
Figure 2A
). Left and right mandible respectively with four and five apical teeth, a strong tapered tooth present distally on left molar plate and a hollow present in place on opposite side (
Figure 2B
). Maxillary lamella 5 with long basal teeth, no distinct beard-like appendix observed (
Figure 2C
). Papilla of maxillary outer lobe with four setae, one basal, one apical and two median, the apical one much stronger; sublobal plate with four guard setae (
Figure 2D
). Labial palp A–E (
Fjellberg 1998
) with zero, five, zero, four, seven guard setae, hypostomal setae H rod-like, h
1
thicker and longer than h
2
(
Figure 2E
). Proximal, basomedian and basolateral area of labium each with about 40 setae.
Figure 1. Body size and colour pattern of specimens in alcohol. (A)
Pogonognathellus heterochros
sp. nov.
; (B)
Pogonognathellus mai
sp. nov.
Dorsal chaetotaxy.
Macrochaetotaxy as in
Figures 2F
and
3A
. Dorsal head with two, four anterior and two posterior macrochaetae; 4 + 4 posterior marginal setae arranged in a loose row (
Figure 2F
). Macrochaetae on each tergum with one to six guard microchaetae and bothriotricha without those accessory setae around it. Abd. IV without anterior macrochaeta (
Figure 3A
).
Legs.
Trochanteral organ reduced to one, one slender spiny seta; some shorter smooth spiny setae present over a distance around trochanteral organ, sockets of them rounded and big as those of setae on trochanteral organ (
Figure 3B
). Tibiotarsus with zero, zero, two blunt spiny inner setae (
Figure 3C
). Tenent hair apically spatulate, much shorter than inner side of unguis. Unguis relatively straight, curved only at tips, with four, four, four inner teeth and a pair of pseudonychia. Unguiculus about two-thirds the length of unguis and with one inner tooth (
Figure 4A
).
Abdominal appendages.
Ventral tube covered by scales and setae both anteriorly and posteriorly; each side of anterior face with about 40 setae in different sizes, three of which larger than others. Tenaculum with 4 + 4 teeth, corpus unscaled and with one seta shorter than rami (
Figure 4B
). Furcula ratio as 4.3–5.0: 5.3–6.6: 1.0 from manubrium to mucro. Manubrium with lateral row of 11–13 large blunt setae, both dorsal and ventral face scaled and no distinct “principal setae” appearing on dorsal face. Inner bases of dentes bearing a pair of large pointed scales with a few striate sculptures on surface. Dental spine formula as II
/
7–10, II. Spines all simple, with irregular longitudinal streaks, basal pair on medial dental parts distinctly smaller than others (
Figure 4C
). Mucro elongate, basal two teeth close to each other, distance from base of mucro to inner basal tooth about 1
/
12 length of mucro, apical and subapical teeth subequal, dorsal lamella with 6–11 intermittent teeth. Apical mucronal setae much larger than others (
Figure 4D
).
Types
Female
holotype
and
two female
paratypes
on slides and
five
in alcohol in
NJU
. Location:
Erdaobaihe Town
,
Antu County
,
Yanbian Korean Autonomous Prefecture
,
Jilin Province
,
China
. In forest litter. Collected by
CHEN Jianxiu
,
MA Yitong
and
YU Daoyuan
.
Figure 2.
Pogonognathellus heterochros
sp. nov.
(A) Labrum; (B) mandible; (C) maxillary head (1–6: lamella 1–6); (D) maxillary outer lobe; (E) hypostomal setae in labial pulp; (F) dorsal cephalic macrochaetotaxy.
Figure 3.
Pogonognathellus heterochros
sp. nov.
(A) Dorsal tergal macrochaetotaxy; (B) trochanteral organ; (C) spiny inner setae on hind tibiotarsus.
Figure 4.
Pogonognathellus heterochros
sp. nov.
(A) Claw; (B) tenaculum; (C) dental spines; (D) mucro.
Etymology
Named for its unique cuticular colour. Greek word
hetero
for different,
chros
for pigmentation.
Remarks
Pogonognathellus heterochros
sp. nov.
is similar to
P. flavescens
in details, such as unguis, dental spines and mucro, but it lacks the long beard-like appendix at the base of maxillary lamella 5, which is a significant character in
P. flavescens
(
Yosii 1967
; Fjellberg; 2007;
Felderhoff et al. 2010
). This new species can be easily recognized by the unique body colour in alcohol.