The Odonata (Insecta) of Patagonia: A synopsis of their current status with illustrated keys for their identification
Author
Muzón, Javier
Author
Pessacq, Pablo
Author
Lozano, Federico
text
Zootaxa
2014
3784
4
346
388
journal article
46101
10.11646/zootaxa.3784.4.2
392d0637-1e41-476c-9f59-b5565720ee40
1175-5326
225033
D24E3364-03AC-48E3-891C-DF4E20EE604F
Austropetaliidae
(
Figs. 55
,
56
a)
This small family of four genera and 10 species (
Garrison
et al.
2006
) is represented also in
Australia
and Tasmania. In Patagonia it is represented by the genera
Hypopetalia
(monotypic:
H. pestilens
) and
Phyllopetalia
, with five species:
P. apicalis
,
P. apollo
,
P. excrescens
,
P. pudu
and
P. stictica
.
All the species are present in southern
Chile
, but only
H. pestilens
,
P. apollo
and
P. pudu
have also been recorded in southwestern
Argentina
(von Ellenrieder 2005;
Pessacq & Brand 2009
).
FIGURE 55.
Distribution maps. a
Hypopetalia pestilens
and
Phyllopetalia excrescens
; b
P. stictica
and
P. pudu
.
FIGURE 56.
Distribution maps. a
Phyllopetalia apollo
and
P. apicalis
; b
Erythrodiplax corallina
,
E. ochracea
, and
E. nigricans
.
Phyllopetalia altarensis
has been recorded from central
Chile
(von Ellenrieder 2005), and it is included here since its known distribution area is close to the northern limit of Patagonia.
The genus
Phyllopetalia
was revised by von Ellenrieder (2005), who synonymized four genera, four species, and one subspecies, provided keys for adults (herein reproduced) and distributional and taxonomic information. The larval knowledge of the family is still poor, with only the larvae of
H. pestilens
and
P. apollo
known (
Schmidt 1941
;
Pessacq & Brand 2009
) with certainty. The larva of
P. stictica
was described by supposition (
Schmidt 1941
), and some characters of
P. pudu
were provided by
Pessacq & Brand (2009)
, also associated by supposition.
Austropetalids mainly inhabit shaded forests with small streams and rivulets.
Carle (1996)
mentions a semiterrestrial habitat for
Phyllopetalia
,
Baird (2013)
observed a larva that he tentatively identified as a
Phyllopetalia
sp. under a log next to a water-filled micro-depression, and
Pessacq & Brand (2009 and pers. obs.)
found larvae of
Hypopetalia pestilens
,
Phyllopetalia apollo
and
Phyllopetalia
sp. in small streams (
1–2 m
wide) within
Nothofagus
forest and on non-native Douglas-fir (
Pseudotsuga menziesii
) plantations. Larvae were found in crevices of small falls, clinging under logs or between pebbles and debris. The characteristic lateral lobes of the abdominal segments having a serrated aspect possibly mimicks
Nothofagus
leaves. Exuviae of
Phyllopetalia apollo
have been found at the top of a pine tree (
Pinus contorta
) cut at a height of about
2 m
(
Pessacq & Brand 2009
).
Females of
Phyllopetalia apollo
have been seen flying close to the water's surface and ovipositing in the moist surface of logs protruding from water; adults of
Hypopetalia pestilens
have been seen flying close to the water's surface, but also at tree-top level, at heights of more than
10 m
(Pessacq pers. obs.). On several occasions males and females have been captured with malaise traps placed across small shaded streams (
Muzón & Spinelli 1995
).
Neopetaliidae
(
Fig. 52
b)
This monotypic family was established by
Carle & Louton (1994)
for
Neopetalia punctata
. This remarkable species has a restricted distribution from 33º S in central
Chile
to 43º S, being recorded in the
Nothofagus
forest of
Argentina
approximately between 40º S and 43º S and from sea level to
1,700 m
.a.s.l. (
Carle & Louton 1994
;
Muzón 1997a
).
Larvae are shallow burrowers and were found in small muddy streams and seepages (
Carle & Louton 1994
); in
Argentina
this species has been found in small shaded streams with riparian bamboo patches within
Nothofagus
forests. Adult behavior has been described by
Carle & Louton (1994)
.
Libellulidae
(
Figs. 56
b, 57)
This cosmopolitan family is represented in Patagonia by seven species in three genera:
Dasythemis mincki
,
Erythrodiplax atroterminata
,
E. connata
,
E. corallina
,
E. nigricans
,
E. ochracea
, and
Sympetrum villosum
.
The biogeographical aspects of these species differ considerably. For example,
D. mincki
is recorded in Patagonia only from the Valcheta stream headings in Somuncura volcanic plateau, where it is locally abundant. The presence of this neotropical species in northern Patagonia, disjunct some
1,000 km
southeast of the nearest population (Uspallata river, Mendoza province), could be explained by the thermal nature of the stream headings on this plateau (
Muzón 1997a
;
Spinelli & Muzón 2000
;
Muzón
et al.
2005
). On the other hand, the cosmopolitan genus
Sympetrum
is represented only by the endemic
S. villosum
, which is a common inhabitant of ponds of the
Nothofagus
forest area between 41° S and 46° S (Muzón & von
Ellenrieder 1997
). Finally, the species of the neotropical genus
Erythodiplax
present in Patagonia have large distribution areas within
Argentina
, except for
E. connata
, a true Patagonian species, which extends slightly north to the southern portion of Mendoza province (del
Palacio & Muzón 2012
); all the species of
Erythrodiplax
are represented in Patagonia by their southernmost populations.
Most of the non-strict Patagonian
Erythrodiplax
are inhabitants of ponds and marshes, being rare in the northern steppe area (north to 42º S), except for
E. corallina
which is recorded both in the forest area of
Chile
and in the steppe areas of
Argentina
.
Erythrodiplax connata
is a common and locally abundant species north to 44º S.
In the northern steppe, only three libellulids have been recorded in sympatry:
Dasythemis mincki
,
Erythrodiplax atroterminata
,
and
E. connata
(
Muzón
et al.
2005
;
Muzón
et al.
2010
). There are two other libellulids recorded in the steppe,
Erythrodiplax corallina
and
E. nigricans
, but only from isolated records; however, it is likely that all five will be found in sympatry.
All the larvae of Patagonian libellulids have been described (
Carvalho
et al.
1991
; von
Ellenrieder & Muzón 2000
; von Ellenrieder 2007;
Garré
et al.
2008
; Lozano
et al.
2011). Those of
Sympetrum
and
Dasythemis
are easily recognized by labial palp features. Larvae of
Erythrodiplax
are harder to identify at the specific level, except for that of
E. connata
, the only one without lateral abdominal spines.
FIGURE 57.
Distribution maps. a
Erythrodiplax atroterminata
and
E. connata
; b
Sympetrum villosum
and
Dasythemis mincki clara
.
FIGURE 58.
Distribution maps. a
Gomphomacromia paradoxa
and
G. chilensis
; b
Rialla villosa
.
Corduliidae
(
Fig. 58
)
Dijkstra
et al.
(2013)
proposed a restricted
Corduliidae
, excluding the genus
Gomphomacromia
which is left as
incertae sedis
within Libelluloidea. For practical purposes we include this genus in
Corduliidae
.
Corduliidae
is a cosmopolitan family represented by only two genera and three species in Patagonia:
Gomphomacromia chilensis
,
G. paradoxa
, and
Rialla villosa
. The genus
Rialla
is monotypic and endemic.
The genus
Gomphomacromia
was revised by von
Ellenrieder & Garrison (2005)
, who synonymized
G. mexicana
Needham, 1933
, with
G. chilensis
,
and
G. etcheverry
Fraser, 1957
, with
G. paradoxa
.
Gomphomacromia chilensis
is a poorly known species endemic to central
Chile
, reaching Patagonia at its northern border, approximately 35º S; locality data are few.
Gomphomacromia paradoxa
occurs all along the Andean range approximately from 32º to 51º S.
The larvae of
Gomphomacromia paradoxa
and
Rialla villosa
have been described (
Needham & Bullock 1943
;
Theischinger & Watson 1984
); that of
G. chilensis
remains unknown.
Gomphomacromia paradoxa
inhabits mountain streams, seepages and bogs, and it can be found in large numbers; males defend their territory and tandems land by the side of the streams (von
Ellenrieder & Garrison 2005
). Larvae of this species seem to be semi-terrestrial (von
Ellenrieder & Garrison 2005
).
Rialla villosa
inhabits lakes and ponds in the
Nothofagus
forest. Adults fly straight close to the water; copulation takes place during flight; tandems perch on trees (
Jurzitza 1975
), adults perch occasionally on grass and bushes, usually in vertical position (
Jurzitza 1989a
). Larvae were collected in oligotrophic lakes with the aid of dredges from
20 m
depth (Muzón 1995).