Two new American species of Paraxenylla (Collembola: Hypogastruridae) and ecological notes
Author
Palacios-Vargas, José G.
Author
Janssens, Frans
text
Zootaxa
2006
1312
37
47
journal article
10.5281/zenodo.173898
61eaa0c9-4192-455a-bb40-ac6a5bddc5c0
11755326
173898
Paraxenylla peruensis
sp. nov.
(
Figs. 11–20
)
Body length (n = 5) 1,230 µm (range 1,020–1,480 µm). Body with moderate short acuminate setae (13–15 µm). Macrosetae and sensorial setae long (26–28 µm) almost two times the length of ordinary setae. Color dark blue, eye patches black.
Ratio head:antenna = 1:0.7. Antennal segment I with 7 dorsal setae. Antennal segment II with 11 setae. Antennal segment III sensory organ consists of 2 small sensilla, chop shaped, 2 longer guard setae and one external microsensillum. Antennal segment IV with four cylindrical sensilla, one smaller than others, one microsensillum, one subapical organ and a simple apical bulb. There are also several acuminate setae and some thicker curving setae with apex truncate similar to sensilla (
Fig. 11
).
Labrum with /5,5,4 setae. 5 + 5 eyes well pigmented.
Mandible with 4–5 teeth. Maxillae with six hypertrophied fringed lamellae. Labium with a well developed internal process.
Prothorax with 5 + 5 setae (sometimes 4 + 4) (
Fig. 12
). Dorsal chaetotaxy head and thorax in
Fig. 12
. Trochanters with 5 setae, femora I, II, III with 11, 11, 10 setae respectively; tibiotarsi I, II, III with 19, 19, 18 setae respectively (
Fig. 13
).
Tibiotarsi with clavate tenent hairs, one dorsal, one ventraldistal, two ventralproximal. Tibiotarsal setae from 11 to 25 µm, tenent hairs 40 µm. Unguis about 35 µm long, without teeth, no empodial appendix.
Dorsal chaetotaxy of abdomen in
Fig. 14
, with a hyperthrichosis of the dorsal abdominal segments I to III. Ventral tube with 1 + 1 setae (
Fig. 15
). Abdominal segment II with three ventral setae on each side (
Fig. 16
). Tenaculum with 3 teeth on each ramus (
Fig. 17
). Mucrodens (85 µm) with two setae (
Fig. 18
). Female with 3 + 3 pregenital setae, 6 genital and 2 eugenital (
Fig. 19
). Males with 3 + 3 pregenital, 6 circumgenital and 8 eugenital setae (
Fig. 20
). Anal plate with 11 setae.
Derivatio nominis
: from the country where this species was found:
Peru
.
Type
locality:
Peru
: Departamento de Ica: Baha de Paracas, Reserva Nacional de Paracas.
Type
Material:
Holotype
Ψ, two
paratypes
ΨΨ will be send to Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima,
Peru
; two
paratypes
ΨΨ, and one
paratype
♂ will kept at senior author’s collection; 2
paratypes
kept at junior author's collection,
9V2003
. All specimens collected at the beach on green algae
Ulva
sp. A. Catanazzi col.
Discussion: The most distinctive and easy character to separate
Paraxenylla peruensis
sp. nov.
from the others is the presence of one smaller sensillum on Ant. IV. The tenent hairs position on tibiotarsi is a differential character, one being dorsodistal, one ventrodistal and two ventroproximal. Among all the congeneric species this is the only one with this combination. This is the biggest species, almost
1.5 mm
. The European
P. affiniformis
(
Stach, 1930
)
sensu
Gama & Deharveng, 1984
measures between 750–900 µm.