Review of the genus Onychiurus Gervais, 1841 (Collembola: Onychiuridae) with description of a new cave species from Southern Spain
Author
Arbea, Javier
text
Zootaxa
2012
3564
33
46
journal article
10.5281/zenodo.209507
8349ed10-9886-46f0-a15e-226496c8bc26
1175-5326
209507
Onychiurus gevi
sp. nov.
Figs. 1–12
Type
locality.
Spain
, Sima Gesm, Coordinates
36º41’32’’N
,
5º00’22’’W
,
1752 m
a.s.l. in the Sierra de las
Nieves
karst of Tólox (Province of Málaga).
Type
material.
Holotype
: female (mounted on slide labelled EML0017):
Spain
, Málaga, Tólox, Sierra de las
Nieves
karst, Sima Gesm,
27.VIII.2006
, G.E.V. (Speleological Club of Villacarrillo) leg.
Paratypes
: one reproductive male, seven females (mounted on slides labelled EML0017).
Holotype
and
paratypes
deposited in The Museum of Zoology at Pamplona, University of Navarra.
Other material.
One female (mounted on slide labelled EML0016):
Spain
, Málaga, Tólox, Sierra de las
Nieves
karst, Sima Gesm,
15.VII.2006
, G.E.V. leg. Two males and three females (mounted on slides labelled EML0034):
Spain
, Málaga, Tólox, Sierra de las
Nieves
karst, Sima de Raja
Helada
(TO-8), Coordinates
36º41’35’’N
,
5º00’27’’W
,
1747 m
a.s.l.,
12.X.2009
, Patricia Carrasco leg. All specimens deposited in the private collection of the author.
Etymology.
The species is dedicated to the members of the Speleological group of Villacarrillo (G.E.V.), who collected specimens of this species from Málaga caves.
Description.
Colour white in alcohol. Body length (excluding antennae) of adults:
holotype
2.8 mm, reproductive males 1.77–2.29 mm, reproductive females 2.27–3.02 mm. Cuticle granulation more or less uniform and fine, somewhat coarser on terga, head capsule, and around anal spines.
Antennal bases well marked. Antennae slightly shorter than head; ratio antennae/head diagonal = 0.86. Ant. IV with subapical organite; microsensillum in latero-external position, approximately two-fifths length from the base; sensilla not well distinguishable from ordinary chaetae; invaginated apical bulb small. Ant. I, II and III with 8, 14 and 17 chaetae respectively. AIIIO as in
Fig. 5
, with five papillae, two small sensory rods, two bent and smooth sensory clubs, four guard chaetae, and lateral microsensillum.
PAO consists of 16–17 finely granulated vesicles (
Fig. 6
). Labrum as in
Fig. 7
with 5,4,2 chaetae. Labial palp of
type
A with five proximal chaetae; labial papillae A, B, C, D and E with 1, 4, 0, 3 and 3 guard chaetae respectively (
Fig. 8
); chaetotaxy of the basomedian field (submentum) with 4+4 chaetae (
Fig. 8
), basolateral field (mentum) with 5 chaetae (
Fig. 8
); outer maxillary lobe with one basal chaeta and without sublobal hairs (
Fig. 8
). Mandible with strong molar plate and four (rarely five) apical teeth as in
Fig. 9
; maxilla bearing three teeth and six lamellae as in
Fig. 10
.
Dorsal pseudocellar formula 32/033/44433, ventral 11/000/0101; all subcoxa I with one pseudocellus. Parapseudocelli not visible on the body.
Dorsal chaetotaxy as in
Fig. 1
and
Tables 2–4
; nearly symmetrical, poorly differentiated into meso-, and microchaetae, sometimes extra chaetae and asymmetries have been observed; macrochaetae only differentiated on the two last Abd. tergites. Th. II and III with microsensilla located laterally. Body sensilla cylindrical, poorly differentiated. Head with unpaired dorsal chaeta d0. Th. I with 10–11+10–11 chaetae. Th. II to Abd. III with 4,4,3,3,3 chaetae respectively on both sides of axial line and without unpaired axial chaetae. Abd. IV and V without unpaired axial chaetae; rarely chaeta a0 present on Abd. IV. Ratio chaetae M/s = 1.4–1.5 on Abd. V. Abd. VI with 2–3 unpaired axial chaetae: (a0), m0 and p0 (
Fig.11
). Subcoxa I of I, II, III pairs of legs with 2,3,3 chaetae respectively. Anal spines rather short, about 0,6 of inner edge of the claw III length.
TABLE 2.
Onychiurus gevi
sp. nov.
Head chaetotaxy. Abbreviations: m—mesochaeta; s—sensilla; z— chaeta z; “-“––denotes absence of chaeta.
| Chaeta number/serie d sd sd’ |
0 m - - |
1 2 m m m m m m |
3 m m - |
4 m m m |
5 - - m |
6 - - - |
7 - - - |
| v |
- |
m - |
m |
m |
- |
- |
- |
| cm cb |
- - |
- - m - |
m m |
m m |
- m |
- - |
- - |
| cp |
- - |
- |
m |
- |
m |
- |
| p |
- |
m+m m |
m |
z |
m |
m |
m |
g 9 chaetae; g4 absent
FIGURES 1–4.
Onychiurus gevi
sp. nov.
: 1, habitus and dorsal chaetotaxy; 2, habitus and ventral chaetotaxy; 3, chaetotaxy of the antenna; 4, tibiotarsal chaetotaxy and claw of leg III.
FIGURES 5–12.
Onychiurus gevi
sp. nov.
: 5, antennal III sense organ; 6, postantennal organ; 7, chaetotaxy of the labrum; 8, chaetotaxy of the labial complex; 9, mandible; 10, maxillary head with 6 lamellae; 11, dorsal chaetotaxy of abdominal VI; 12, remnant of furca.
TABLE 3.
Onychiurus gevi
sp. nov.
Dorsal thoracic chaetotaxy. Abbreviations: m—mesochaeta; ms—microsensilla; “- “—denotes absence of chaeta; “()”—denotes chaeta present or absent.
Chaeta number/serie 1 2 3 4 5 6
7 Th I
m - - m - m - m Ventral body chaetotaxy as in
Fig. 2
, with 0+0, 1+1 and 1+1 ventral chaetae on pro-, meso- and metathorax respectively. VT with 7–8+7–8 apical chaetae and 1+1 basal chaetae. Furca reduced to a finely granulated area, with 2+2 posterior setulae arranged in one row (
Fig. 12
). Male ventral organ absent.
| p Th II a m ca cp |
m - m m m |
m m m - m |
m m (m) - m |
m m m+(m) m m |
m m m m - |
m+m m m m - |
m m m+ms m - |
| p Th III a |
- - |
m m |
m m |
m m |
m m |
m+m m |
m m |
| m ca cp p |
m m m m |
m - m m |
- - (m) m |
m m m - |
m m - m |
m m m m |
m+ms m+m - m+(m) |
TABLE 4.
Onychiurus gevi
sp. nov.
Dorsal abdominal chaetotaxy. Abbreviations: m—mesochaeta; M—macrochaeta; s—sensilla; AS—anal spines; “-“—denotes: absence of chaeta.
| Chaeta number/serie Abd I-II a m ca p Abd III |
0 |
1 - m m m |
2 m m - m |
3 - - - s |
4 m m m m |
5 - (m) m m |
6 m (m) - m |
7 m m - m |
| a m ca |
- m m |
m m - |
m - - |
m m m |
m - m |
m - - |
m m m |
| p Abd IV a m ca p Abd V a m |
(m) |
m - m - m m m |
m (m) m - m m m |
s m m - s m m |
m+m m m - m m s |
m m m m m m - |
m m m - m m - |
m - m m m M M |
| p Abd VI a |
m |
M m |
- m |
s |
m |
m |
m |
M |
| m p |
m m |
m AS |
M M |
Tibiotarsi I, II, and III with 15–16(7,7–8,1), 15–16(7,7–8,1) and 15(7,7,1) chaetae respectively; distal whorl with seven chaetae (
Fig. 4
). Claws without teeth. Empodial appendage slender, as long as inner edge of a claw, without basal lamella (
Fig. 4
) (appendage length 1.0–1.1 inner edge of claw).
Ecology.
O. gevi
sp. nov.
is bisexual species. It has been collected in cold and wet cave habitats. It has been found together with
Deuteraphorura cebennaria
(
Gisin, 1956
) (
Arbea
et al.
2011
)
.
Discussion.
O. gevi
sp. nov.
resembles the
Onychiurus obsiones
species group
sensu
Kaprus’ (2008). It clearly differs from all members of the group in size (1.7–3.0 in
O. gevi
sp. nov.
versus 0.6–1.0 mm), number of pseudocelli on Abd. tergites I–III (4,4,4 in
O. gevi
sp. nov.
versus 3,3,3), ventral pseudocellar formula (2/000/0101 in
O. gevi
sp. nov.
versus 2/000/0001), and habitat preferences (caves in Málaga, S
Spain
in
O. gevi
sp. nov.
versus soil in mountains beech forest in
Poland
, and sandy habitats in arid and semiarid regions of N Africa, SE Europe, Minor and Middle Asia) (see Kaprus’ 2008 and
Smolis & Skarżyński 2009
).
Some
Onychiurus
species:
O. boldorii
,
O. nathanieli
,
O. paoletti
,
O. stillicidii
also share the same dorsal pseudocellar formula on head and Th. as the new species, but differ in dorsal pseudocellar formula on Abd. (4,4,4,3,3 in
O. gevi
sp. nov.
versus 3,3,3,4,
3 in
O. boldorii
and
O. stillicidii
, 3,3,3,5,3–
4 in
O. nathanieli
, and 3,3,3,5,
3 in
O. paoletti
) and ventral pseudocellar formula (see Table 5).
The new species is distinguished from all other species of the genus by the number of pseudocelli on Abd. I–III (see Table 5).