New species of Andiorrhinus Cognetti, 1908 (Oligochaeta: Rhinodrilidae) from Venezuela and Brazil
Author
Feijoo, Alexander
Author
Brown, George G.
Author
James, Samuel W.
text
Zootaxa
2017
2017-12-08
4363
1
55
78
journal article
31213
10.11646/zootaxa.4363.1.2
ab917453-d6be-4c48-89a0-d3876eab96d0
1175-5326
1096127
1A43116B-C2A7-4B75-A96D-792773417A93
Andiorrhinus
(
Meridrilus
)
timotocuica
sp. nov.
(
Figure 5A–C
,
Table 2
)
Material examined.
Holotype
: Clitellate specimen (MZUSP 01479).
Paratype
1
:
1 adult
(
MZUSP 01480
).
Locality
:
Venezuela
, state of
Mérida
,
Mount Zerpa
(
08°37'N
,
71°09'W
).
Altitude
:
2200 m
a.s.l.
Collection
date:
20 July 1996
.
Collectors
:
Pedro Durant
and
E.J. Arellano
.
Paratype
2
. 1 fragmented adult (
MZUSP 01481
).
Locality
:
Venezuela
, state of
Mérida
, forest of
Psidium
caudatum
(
Myrtaceae
), beside the
Núcleo Universitario
"
La Hechicera
”,
Universidad de Los Andes
(
08º38'00"N
;
71º09'30"W
).
Altitude
:
1950 m
a.s.l.
Collection
date:
18 April 1994
.
Collector
:
Pedro Durant.
Etymology.
The new species was named in honor of the indigenous community Timoto-cuica that inhabits the states of
Mérida
,
Táchira
, and
Trujillo
in
Venezuela
.
Description.
Epiendogeic species, with brown-colored dorsum and light brown clitellum and ventral region, corresponding to the respective color code numbers 703 and 705 (
Seguy 1936
), and cylindrical body.
Holotype
:
The length of the preserved
holotype
is
149 mm
, with a diameter of
3.6 mm
in the preclitellar region,
5.3 mm
in the clitellum, and
2.3 mm
in the postclitellar region. Number of segments: 202.
Paratype
:
136 mm
long and widths of 3.0 mm (segment 9),
3.7 mm
(segment 19), and
1.9 mm
in segment 30. Number of segments: 186. The first and second segments are visible and the long, tentacular-shaped prostomium measures
3.2 mm
. Four pairs of closely paired setae are visible as of segment 5. The hook-shaped common setae measure
0.46 mm
, with no ornamentations (
Fig. 5A
). The distance between the setae in segment 40 is aa:ab:bc:cd:dd = 5.0:1.0:4.3:0.8:13.5 and, in the posterior region in segment 84, is similar to that of segment 40, varying only in cd (0.8) and dd (13.7). The setae of segments 7, 8, 9, and 19–23 are transformed as genital setae which are contained in long follicles that extend to mid-dorsal and are located adjacent to five pairs of glandular masses in segments 19–23,. Genital setae measure
2.36 mm
, are rectilinear and, in the apical ½, present 16 U-shaped ornamentations that end in a spearshaped tip (
Fig. 5B
).
The saddle-shaped clitellum measures
9 mm
and lies in segments 16–25 (=10), with the tubercula pubertatis located between segments ½19 and 19–23 (=4, 4.5). The male pores are located in intersegment 19/20 and female pores in segment 17, close to rows of setae b. The nephropores are aligned with setae c and d. Three pairs of spermathecal pores were observed in intersegments 6/7, 7/8, and 8/9, aligned with setae c and d.
Internal anatomy.
The septa of segments
6/7–10/11
are fine, transparent membranes, septa slightly thicker between segments
11/12–13/14
. The round muscular gizzard and thick, disc-shaped musculature are present in segment 6. Three pairs of large, digitiform calciferous glands with internal lamellar structure are present in segments 7–9, with no appendage in the ectal region; each gland with 24–26 parallel lamellae. The transversal cut of the gland shows that two branches exit the ental region, dividing lamellae into three clusters: one proximal to the border, another central, and another in 2/3. The esophagus-intestine transition begins in intersegment 22/23 and the S-shaped typhlosole begins in segment 23, occupying 1/3 of the intestinal lumen. There are no intestinal caeca. Intestinal content consists mostly of very fine organic matter and trace amounts of minerals. Three pairs of lateral hearts are located in segments 7–9, covering the calciferous glands, and two voluminous intestinal hearts are present in segments 12 and 13. Both supraesophageal and subesophageal vessels are present. There is one pair of holonephridia per segment.
FIGURE 5.
Andiorrhinus
(
Meridrilus
)
timotocuica
sp. nov
.
, holotype.
A.
Common seta, segment 8.
B.
Genital seta b, segment 35.
C.
Spermathecae of 7, 8, 9.
Two pairs of testis sacs enclose the testes in segments 10 and 11, and two pairs of seminal vesicles are present in segments 11 and 12. The two pairs of deferent ducts open towards the male pore in intersegment 19/20. One pair of ovaries is present in the cavity of segment 13; the female pore is located in segment 17. Three pairs of small, equal-sized spermathecae, measuring
1 mm
, are present in segments 7, 8, and 9 (
Fig. 5C
). The sperm duct is invisible and presents a constriction near 1/3 of the length up from the body wall, that separates the seminal chambers from the ampulla, which is slightly oblong with irregular borders. A group of larger-sized bifurcated genital seta glands are located near the base of each spermatheca.
Remarks
.
Andiorrhinus
(
Meridrilus
)
timotocuica
sp. nov.
is closely related to
A.
(
Meridrilus
)
boconius
Righi, 1989
due to the location of male pores in 19/20, and the presence of three pairs of spermathecae in 6/7–8/9. The new species differs from
A. boconius
by the extent of the clitellum (
Table 2
), the shape of the calciferous glands, the number of lamellae in the calciferous glands, as well as the shape of the spermathecae, shape and size of the normal setae, and ornamentation of the genital setae.