Cylindropygus ferox, Deharveng & Potapov & Bedos, 2005

Deharveng, L., Potapov, M. & Bedos, A., 2005, Cylindropygus ferox gen. n., sp. n.: A new member of the Cryptopygus complex (Collembola, Isotomidae) from central France, Journal of Natural History 39 (23), pp. 2179-2185 : 2181-2184

Cylindropygus ferox sp. n.

( Figures 1–13 )

Type material

Holotype male and four paratypes on slide, 35 paratypes in alcohol. France, Cantal , Le Peyrot, commune Cros-de-Montvert, oak litter and soil, 3 November 1996, M. C. Souqual leg. (sample 15–007), 2.1551 ° E, 45.0563 ° N.

Other material

France, Corrèze , commune Hautefage, La Maronne valley, oak litter and soil, 1 April 1981, Deharveng leg. (sample 19–002), two specimens, 2.0001 ° E, 45.0892 ° N .

France, Creuse, commune Boussac, litter and soil in mixed broadleaf forest, Rougerie leg. (sample 23–001), one specimen, 2.2229 ° E, 46.3492 ° N .

France, Creuse, commune Saint-Martin-Château, soil in mixed broadleaf forest, Rougerie leg. (sample 23–002), one specimen, 1.8107 ° E, 45.8478 ° N .

France, Haute-Vienne, commune Saint-Sylvestre, Monts d’Ambazac, chestnut litter, Bedos and Deharveng leg. (sample 87–03), two specimens, 1.3704 ° E, 45.9965 ° N .

Type deposit

Holotype and three paratypes mounted in Marc-André II and 30 paratypes in alcohol deposited in the Muséum national d’Histoire naturelle de Paris. One paratype mounted in Marc-André II and five paratypes in alcohol deposited in the collection of Moscow State Pedagogical University.

Description

Body length 0.65–0.80 mm. Habitus perfectly cylindrical, elongate ( Figure 1 ). Abd.V–VI fused, rounded, V+VI slightly shorter than III. Antennae shorter than head. Entirely white. Integument covered with small elementary hexagonal grains, larger on head.

Dorsal mesochaetae slightly curved, acuminate, smooth; longer on Abd.IV–V where they are weakly but distinctly serrated on one side; not shortened in axial part of tergites. Macrochaetae straight, thin, long and acuminate. S-chaetae thin and rather long, but shorter than nearby mesochaetae.

Mandible slightly asymmetrical, with four teeth, the distal much smaller than the antedistal. Outer maxillary lobe with four sublobal hairs, palp bifurcate ( Figure 2 ). Labral formula 4/5,5,4, with chaetae of the two anterior rows thickened ( Figure 3 ). Labium with three proximal and four baso-median chaetae, full set of guards and papillae. Labial palp papillae A, B, D armed with strong teeth; C with a weaker one, and E with a normal hair ( Figure 4 ).

Eyes absent. PAO long, curved and sclerotized ( Figure 6 ).

Antennae: Ant.I with two rather short ventro-external S-chaetae of equal length, one thicker; 11 ordinary chaetae; and two basal microchaetae. Ant.II with one thin ventroexternal S-chaeta, 17 ordinary chaetae and three basal microchaetae. Ant.III organ like usual, with five S-chaetae. Ant.IV with a rather large organite with its guard chaeta short. Several clearly recognizable S-chaetae on Ant.IV, four or five rather strongly thickened, three or four lesser thickened and several thin ( Figure 7 ).

Five or six chaetae between axis and pc3-chaeta on head. Frontal chaeta ap present.

Chaetae on body tergites not very abundant ( Figures 5 , 10 ). Axial chaetotaxy 12,8/ 6,6,6,8,4. Macrochaetae rather short on head, but well differentiated on tergites. Macrochaetotaxy: 1,1/3,3,3,4, numerous on Abd.VI ( Figure 10 ). S-chaetotaxy: 4,3/ 2,2,2,3,4 (s), 1,0/0,0,0 (ms) ( Figures 8–10 ). S-microchaeta on Th.II (ms) nearly as long as closest S-chaeta ( Figure 9 ). S-chaetae of Abd.V: two medial (accp1 and accp2) rather long and thin, one lateral (accp3) globular, one ventro-lateral (accp4) thin and of medium size ( Figure 5 ). Sternite of Th.II without chaetae, of Th.III with 2+2 chaetae.

Ventral tube with 4+4 latero-distal and 1+1 postero-basal chaetae. Coxa I with one external chaeta. Tita with 21, 21, 26–27 chaetae, without elongate or clavate tenent hairs. No modified chaetae on male Tita. Claw stout, without inner, lateral or external teeth. Empodial appendage about half as long as inner edge of claw.

Retinaculum with 4+4 teeth and one chaeta. Anterior furcal subcoxa with six chaetae, posterior one with five chaetae (two specimens observed). Manubrium with 1+1 anterodistal chaetae and 9+9 posterior chaetae. Dens of normal shape, rather short (dens: claw III52.8; manubrium: dens51), slightly crenulated on posterior side. Each dens with 9–10 anterior and five posterior chaetae, including a distal microchaeta ( Figures 11, 12 ). Mucro tridentate ( Figure 13 ).

Etymology

The species name refers to the strong teeth of the labium.

Comments

Due to habitus, C. ferox sp. n. is readily recognizable among European Isotomidae .

Ecology

The species is widespread, though not abundant, in forest soils of the mid-part of the Massif Central, France.

Figures

Figures 1–5. (1) Habitus in lateral view showing macrochaetae; because of obliquity, lateral macrochaetae appear shorter than true length (see Figure 10 for real relative size). (2) External lobe of maxilla. (3) Labrum. (4) Labium, with papillae A–E. (5) Abdominal tergite (V+VI).

Figures 6–13. (6) Postantennal organ; vertical arrow, anterior, horizontal arrow, axis. (7) Dorsal S-chaetae of Ant.IV; other chaetae represented by their sockets; dotted line around Ant.IV organ. (8) Third thoracic tergite, lateral part. (9) Second thoracic tergite, lateral part; ms, S-microchaeta. (10) Dorsal S-chaetotaxy and macrochaetaxy; ordinary mesochaetae represented by sockets. (11) Distal part of manubrium and mucrodens, anterior view. (12) Mucrodens, posterior view. (13) Mucro, lateral view.