Taxonomy of the Proisotoma complex. V. Sexually dimorphic Ephemerotoma gen. nov. (Collembola: Isotomidae)
Author
Potapov, Mikhail
Author
Kahrarian, Morteza
Author
Deharveng, Louis
Author
Shayanmehr, Masoumeh
text
Zootaxa
2015
4052
3
345
358
journal article
10.11646/zootaxa.4052.3.4
d4091bed-62c2-44b2-92fa-128702fb8c9e
1175-5326
243233
E746140C-2239-4425-9007-31AC036D852C
Ephemerotoma multituberculata
(
Martynova, 1971
)
comb. nov.
Figs 22–24
,
29–31
,
40
Syn.:
Proctostephanus multituberculatus:
Martynova (1967)
(nomen nudum) Syn.:
Proisotoma multituberculata
Martynova, 1971
Material.
Holotype
and five
paratypes
(
Tajikistan
, Gissar Range, Kondara Canyon, under stones,
26.iv.1965
) deposited in Museum of Zoological Institute St.-Petersburg; two topotypes from the original sample of the
holotype
. One juvenile male, others adult females.
Redescription.
Cuticle finely reticulated. Size of body 1.7 mm. Colour of
paratypes
unknown but stated in original description as yellowish-grey with darker dorsum. Abd.V strongly modified, with large and rather compact group of granules (
Fig. 30
). Chaetae on granulated field slightly thicker. Abd.VI small, partly hidden from dorsal view (cryptopygy), with slightly modified tegument. Ocelli 8+8, G and H smaller. PAO narrowly elliptical, not constricted; as long as 1.4–1.8 ocellus diameter. Maxillary outer lobe with simple maxillary palp and 4 sublobal hairs one of them slightly thicker. Maxillary head compact, with unmodified lamellae. Labral formula as 2/554 (
Fig. 31
). Labium with all papillae (A–E), papillae A–D with normal number of guards (1,4,0,4), E with 4 guards (
3 in
one individual on one side). With 3 proximal and 4 basomedian chaetae. Ventral side of head with 4–5+4–5 postlabial chaetae. Ant.1 with 14
–
15 chaetae, 2 basal microsens (
bms
), one each dorsally (larger) and ventrally, and 2 ventral sens (
s
) of different length. Ant.2 with 3
bms
and 1 laterodistal
s
. Ant.3 without
bms
and with 5 distal
s
(including one lateral spine-like), guard sens of
AO
twice length of inner ones. Sens on Ant.4 weakly differentiated, subapical organite small.
FIGURES 29–33.
Ephemerotoma multituberculata
(29–31) and
Proctostephanus anopolitanus
(32–33): 29, 30, Abd.V, chaetotaxy (29) (granulation not shown) and granulation (30); 31, labrum; 32, Abd.V; 33, dens, posterior view.
Body with numerous and rather short chaetae on body. Dorsal axial chaetom of Th.II–Abd.III as about 10– 11,8/8,8,8,11–13,11–13. Common chaetae of normal shape, smooth. Th.III with 2–4 chaetae on each side of ventral line, Th.I and II without ventral chaetae. Macrochaetae not differentiated, largest chaetae on Abd.V about 0.2 of tergal midline. Sens on tergites clearly differentiated, short. S-formula as 3,3/2,2,2,2,4 (s) and 1,1/1,1,1 (
ms
). Sens on Abd.I–III in front of
p
-row of chaetae. Microsens on Abd. I–III in front of lateral sens. Sens of Abd.V arranged as in
Figs 29, 30
, one pair of long sens and one pair of short (
Figs 29, 30
). Unguis simple without inner and lateral teeth. Ti.1–3 with few additional chaetae: 23–24 on Ti.1–2 and ca. 32 on Ti.3. Tibiotarsal tenent chaetae (1,2,2) as long as U3, very slightly clavate. Femur 1 with 6
a
-chaetae, 1
ae
-chaeta, 3–4
e
-chaetae, and 10–12 chaetae of
pe-ppi-i
-group. Ventral tube usually with 4+4 laterodistal chaetae. Tenaculum with 3+3 teeth and one chaeta. Anterior furcal subcoxae with 10–13, posterior ones with 7–8 chaetae. Anterior side of manubrium with 1+1 chaetae, more rarely with 1+2 or 2+2 distal chaetae, posterior side with 16–20+16–20 chaetae on main part and 6+6 chaetae laterobasally, without chaetae on lateral sides. Dens stout, with 3 (2
–
4) chaetae (
Figs 22–24
), posterior side of dens without clear humps and with 6–8 chaetae. Mucro with 2 teeth. Ratio of manubrium: dens: mucro = 4.3–5.7: 2.9– 3.6: 1.0.
Affinity
. The species is well defined due to the combination of a triangular "2 + 2 " s-pattern on Abd.V (shared with
E. huadongensis
) with the presence of ventral chaetae on Th.III (shared with other species). The modification of the tegument at the end of abdomen is unique. We have seen only one juvenile male and thus reliable conclusions on sexual dimorphism cannot be made.
Distribution.
Known only from the
type
locality.