- - - - - - - - - - - - - - - - - - - - - - -
7.2 Sagitta gazellae von Ritter-Zahony,
1909
Sagitta gazellae von Ritter-Zahony, 1909: pp.
787, 788 - von Ritter- Zahony 1911 b: p. 1 O, figs. 47- David, 1955: p. 246, figs. 1, 5a,b, 6b,c, 9, 10,
11a, b, 12a-d- Dinofrio, 1973: p. 26, pl. 1 fig. 3,
pl. 2 fig. 3a,b - Alvarifio, 1962: p. 27, fig. 5a,b -
Alvarifio, 1969: p. 158, figs. 48a-c, 49a-g- Boltovskoy, 1981: p. 788, fig. 256.
Sagitta hexaptera Fowler, 1907: p. 1.
Sagitta lyra Thomson, 1947: p. 11.
Pseudosagitta gazellae Bieri, 1991a: p. 128- Lutschinger, 1993: p. 24, figs. 10a,b.
Body length -
21-65 mm
Description. Body elongated, flaccid and transparent. Anterior fins much longer than posterior
(almost double), commencing behind ventral
ganglion. These are connected to the posterior
fins by a narrow hand. Rays are visible along externa! margin, especially in posterior half. Posterior fins subtriangular with rays along externa!
border. Posterior extremity of fins almost reaching seminal vesicles. Corona ciliata pear-shaped
and commencing anterior to eyes. Number of
hooks varies from 5-10; number of anterior and
posterior teeth varies from 5-1 O and 3-10, respectively. Hooks and teeth more numerous in
larger specimens.
Remarks
The species has been reported to reach 105 mm
in length in sub-Antarctic waters (David 1955) as
compared to the maximum length of 65 mm re~orded for Magellan specimens. This latter specImen had an ovary that was only 6 mm in length
with eggs arranged along 8 rows. The longest
ovary (23 mm) was still somewhat unripe and
was observed in a specimen of 60 mm. The only
specimen sampled in the eastern sector of the
Straits, at the mouth of Baia Inutil, was 57 mm in
length with an ovary of 22 mm, the eggs of which
were stiU immature.
Distribution
S. gazellae is an oceanic species widely distributed throughout the circumpolar Antarctic. It was
originally considered only Antarctic in its distribution but, according to David (1955), maximum densities occur in sub-Antarctic regions,
where it has been found tobe 3 times as abundant as in the Antarctic. The northern limits of
its distribution in the austral ocean correspond
to the subtropical convergence, the position of
which changes according to the Aghulas and SE
Australian currents. It is probable that such
changes also influence the northern limits of the
distribution of S. gazellae. David (1955) records
the presence of the species at the 35° parallel off
the Argentine coast, whereas Kapp (1980) reports it somewhat more south at the 40° parallel.
The species was also sampled in the Pacific
Ocean, at the 50° parallel north of the Convergence, by Guglielmo et al. (1992). New records of
S. gazellae are reported near New Zealand
(North and South Islands) by Lutschinger
(1993).
7.2 Sagitta gazellae von Ritter-Zahony,
1909
Sagitta gazellae von Ritter-Zahony, 1909: pp.
787, 788 - von Ritter- Zahony 1911 b: p. 1 O, figs. 47- David, 1955: p. 246, figs. 1, 5a,b, 6b,c, 9, 10,
11a, b, 12a-d- Dinofrio, 1973: p. 26, pl. 1 fig. 3,
pl. 2 fig. 3a,b - Alvarifio, 1962: p. 27, fig. 5a,b -
Alvarifio, 1969: p. 158, figs. 48a-c, 49a-g- Boltovskoy, 1981: p. 788, fig. 256.
Sagitta hexaptera Fowler, 1907: p. 1.
Sagitta lyra Thomson, 1947: p. 11.
Pseudosagitta gazellae Bieri, 1991a: p. 128- Lutschinger, 1993: p. 24, figs. 10a,b.
Body length -
21-65 mm
Description. Body elongated, flaccid and transparent. Anterior fins much longer than posterior
(almost double), commencing behind ventral
ganglion. These are connected to the posterior
fins by a narrow hand. Rays are visible along externa! margin, especially in posterior half. Posterior fins subtriangular with rays along externa!
border. Posterior extremity of fins almost reaching seminal vesicles. Corona ciliata pear-shaped
and commencing anterior to eyes. Number of
hooks varies from 5-10; number of anterior and
posterior teeth varies from 5-1 O and 3-10, respectively. Hooks and teeth more numerous in
larger specimens.
Remarks
The species has been reported to reach 105 mm
in length in sub-Antarctic waters (David 1955) as
compared to the maximum length of 65 mm re~orded for Magellan specimens. This latter specImen had an ovary that was only 6 mm in length
with eggs arranged along 8 rows. The longest
ovary (23 mm) was still somewhat unripe and
was observed in a specimen of 60 mm. The only
specimen sampled in the eastern sector of the
Straits, at the mouth of Baia Inutil, was 57 mm in
length with an ovary of 22 mm, the eggs of which
were stiU immature.
Distribution
S. gazellae is an oceanic species widely distributed throughout the circumpolar Antarctic. It was
originally considered only Antarctic in its distribution but, according to David (1955), maximum densities occur in sub-Antarctic regions,
where it has been found tobe 3 times as abundant as in the Antarctic. The northern limits of
its distribution in the austral ocean correspond
to the subtropical convergence, the position of
which changes according to the Aghulas and SE
Australian currents. It is probable that such
changes also influence the northern limits of the
distribution of S. gazellae. David (1955) records
the presence of the species at the 35° parallel off
the Argentine coast, whereas Kapp (1980) reports it somewhat more south at the 40° parallel.
The species was also sampled in the Pacific
Ocean, at the 50° parallel north of the Convergence, by Guglielmo et al. (1992). New records of
S. gazellae are reported near New Zealand
(North and South Islands) by Lutschinger
(1993).