New species and a new record of Isotomidae (Collembola) from the coast of Brazil
Author
Abrantes, Eduardo Assis
Author
Mendonça, Maria Cleide De
text
Zootaxa
2007
2007-06-07
1500
1
55
60
journal article
10.11646/zootaxa.1500.1.2
11755334
5088000
8ED9B600-B548-4192-8B65-A44F3DAE5DB2
Archisotoma catiae
sp. nov.
Figs
1
–10
Description.
Habitus typical of the genus. Body length
0,49–0,55mm
. Color grayish interspersed with pale spots. Tegumentary granulation very fine. Body setae short and simple.
Dorsal chaetotaxy of the head and the body with thin, short and simple setae as show in
Figs 1 and 2
.
Antennae (
Fig. 3
) slightly shorter than head; ratio antenna: head =
117µm
:
118µm
. Ant. IV with 12 dorsal sensilla (
11 µm
), one lateral microsensillum and sub apical organ present (
Fig.4
). Ant. III with about 39 setae and 1 ventral microsensillum. Ant II with about 22 setae and 2 basal microsetae, 1 ventral and 1 dorsal. Ant. I with about 15 setae and 1 basal microseta. Antennal segments ratio I:II:III:IV = 1:1,4:1,9:2,3.
FIGURES 1–10.
Archisotoma catiae
sp. nov.
: 1, dorsal cephalic chaetotaxy; 2, dorsal chaetotaxy of tergites, dorsolateral view; 3, antennal segments; 4, apical organ of the antennal segment IV; 5, maxillae; 6, mandibulae; 7, abdominal segments V–VI; 8, leg III; 9, ventral tube; 10, subcoxa and furca.
Eyes 6+6 and long darkly eye patch area. Postantennal organ oval, about 3 times as long as diameter eye and surrounded by 5 setae (
Fig. 1
). Labrum with 5,5,4 setae and 2 prelabral setae; clypeal setae not studied. Maxillary capitulum complex, long and slender, unidentate equal size of the internal lamellae; three maxillary lamellae the ventral external and ventral internal with fringes (
Fig. 5
); molar plate as in figure 6.
Axial dorsal chaetotaxy from thorax II to abdominal III as 7,5/3,3,3. The sensilla in thoracic segments are indistinct from the common setae. Abdominal segment IV with 3 axial anterior unpaired setae and 2+2 axial posterior paired setae. Abdominal segment V with 3+3 axial setae and abdominal segment VI with 5 unpaired setae (
Fig. 7
). Abdominal VI with 2+2 trichobothria thin and smooth, the first pair longer (
35 µm
) than the second pair (
15 µm
), separated by 3 setae from the first pair.
Tibitarsi I, II and III contains 22,25,26 setae respectively (In
Holotype
). Tibiotarsus III with thick apical spur (
6µm
). Unguis untoothed (
12µm
); empodial appendage short and lanceolated about half the unguis length (
Fig. 8
). Ventral tube with 4+4 laterodistal setae (
Fig. 9
). Tenaculum with 4+4 teeth and one seta on corpus. Subcoxa furcalis: anterior with about 16 setae and posterior with about 13 setae. Manubrium with 23 setae on anterior surface and no posterior setae. Dens with 9 setae on anterior side setae and 9 setae on posterior side. Mucro with three asymmetrical teeth, the apical tooth bigger than the others, with basal setae. Ratio of manubrium:dens:mucro = 4,9:4,2:1 (
Fig. 10
).
Type
locality.
Restinga de Maricá
,
Maricá
city,
Rio de Janeiro State
,
Brazil
.
Found
in sand dunes
.
Type material.
Brazil
:
Rio de Janeiro State
:
Maricá
city,
Restinga de Maricá
, male
holotype
on slide Nº 1320
CM
/
MNRJ
,
25.vi.2003
, L.H. Fernandes & E.A. Abrantes, coll.;
three paratypes
on slide Nº 1314
CM
/
MNRJ
,
25.vi.2003
;
two paratypes
on slide Nº1320
CM
/
MNRJ
,
25.vi.2003
;
two paratypes
on slide Nº1320
CM
/
MNRJ
,
25.vi.2003
;
three paratypes
on slide Nº 1259
CM
/
MNRJ
,
31.vii.2003
;
one paratype
on slide Nº 1260
CM
/
MNRJ
,
31.vii.2003
.
Discussion.
Archisotoma catiae
sp. nov.
belongs to the
besselsi
group, which is represented by 11 species and characterized in according to
Potapov (2001)
by small size, tibiotarsi III with stiff outer spur, maxillary head with thin simple capitulum, 3–2 pairs of trichobothria on abdominal segment VI.
Archisotoma catiae
sp.nov.
shows a variable number of setae in tibiotarsi I, II and III with the variation includes species with 22, 23, 22 to 23, 29, 27 setae respectively. The new species is closest to
A. vaoensis
Thibaud & Weiner, 1997
described from
New Caledonia
by the number of prelabral setae, the dens chaetotaxy and the number of setae between the anterior trichobothria.
Archisotoma catiae
sp.nov.
can be distinguished by the number of setae in tibiotarsus I, II and III, the body chaetotaxy and the size of maxillary capitulum. In
A. vaoensis
the number of setae in tibiotarsus I, II and III: 23, 28, 28; the axial chaetotaxy from thorax II to abdominal I: 8,5/4 (
Thibaud & Weiner 1997
); the maxillary capitulum is reduced, as half size of the internal lamellae (Thibaud & Palacios- Vargas 2001), but in the new species the number of setae in the tibiotarsus I, II and III is variable, the axial chaetotaxy from thorax II to abdominal III is 7,5/3,3,3 and the size of the maxillary capitulum is equal of the internal lamellae.
Derivatio nominis.
This species is dedicated to our great friend Dr. Cátia Antunes Mello-Patiu.