First record of the ant genus Oxyepoecus (Formicidae: Myrmicinae: Solenopsidini) in Chile, with remarks on its geographical range
Primer registro del género de hormigas mirmicinas Oxyepoecus (Formicidae: Myrmicinae: Solenopsidini) para Chile con consideraciones sobre la amplitud de su distribución
Cuezzo, Fabiana
CONICET - Instituto Superior de Entomología «Dr. A. Willink». Facultad de Ciencias Naturales e IML, UNT. Miguel Lillo 205. CP 4000, San Miguel de Tucumán, Argentina; e-mail: fcuezzo@csnat.unt.edu.ar
RESUMEN. El género de hormigas Oxyepoecus (Formicidae: Myrmicinae: Solenopsidini) Santschi, 1926, está compuesto por 16 especies reconocidas como válidas. Tres de estas especies, O. inquilinus, O. bruchi y O. daguerrei, son consideradas actualmente como vulnerables (VuD2) e incluidas en la lista roja de especies amenazadas. El propósito de este trabajo es registrar, por primera vez, una de estas especies para Chile: O. inquilinus. Esta nueva localidad constituye el límite de distribución austral de este género rara vez recolectado.
PALABRAS CLAVE. Especies amenazadas; Formicidae; América del Sur; Chile.
ABSTRACT. The ant genus Oxyepoecus (Formicidae: Myrmicinae: Solenopsidini) Santschi, 1926 has 16 species recognized as valid. Three of these species: O. inquilinus (Kusnezov, 1952), O. bruchi Santschi, 1926 and O. daguerrei (Santschi, 1933) are considered as vulnerable (VuD2) and included in the Red List of threatened species. The aim of this paper is to record one of these species: O. inquilinus in Chile for the first time, adding a new locality to be considered as the southernmost limit of distribution for this relatively rarely collected ant genus.
KEY WORDS. Endangered species; Formicidae; South America; Chile.
The ant genus Oxyepoecus (Formicidae:
Myrmicinae: Solenopsidini) was created by
Santschi (1926). Oxyepoecus is exclusively
neotropical and workers are seldom
collected. The genus was reviewed by Kempf
(1974) and recently the Vezenyii group was
proposed and reviewed by Albuquerque &
Brandão (2004). The last authors propose a
new generic diagnosis dividing Oxyepoecus
in two complex: Vezenyii with 11 species and
Oxyepoecus grouping the remainder five
species.
Oxyepoecus can be distinguished from
other Solenopsidini ant genera by the
following suite of characters: 11 segmented
antennae with a 3-segmented apical club; clypeus with four teeth; propodeum with a
pair of teeth and integument always
extensively sculptured.
As Albuquerque & Brandão (2004) say:
«all known individuals of Oxyepoecus were
obtained either by chance discoveries or
specialized collecting techniques applied
sporadically at very few and scattered
localities».
The use of new techniques and protocols,
as is the case of leaflitter Winkler extractor,
soil samples and/or Berlesse funnel to sample
soil and leaf litter, has permitted to obtain, in
a more efficient way, relatively small ants that
inhabit specifically these niches, up to a
decade ago very little studied.
Until today, the southern limit of
Oxyepoecus distribution was the parallel 31º,
in Argentina (Cordoba, Alta Gracia) (fig.2).
O. inquilinus (Kusnezov, 1952) was formerly
recorded from Central and Southern Brasil
and Tucumán, in northern Argentina. The
northern limit of its distribution was recently
mentioned by Fernandez (2002) to Llanos
Orientales, Meta Department, Orinoco Basin,
Colombia. Here, I provide the first record of
Oxyepoecus in Chile, being the new
southernmost record that is known for this
genus.
One worker of Oxyepoecus inquilinus
was collected in 06 February 2005 by M.
Ramírez and F. Labarque (Museo de Ciencias
Naturales B. Rivadavia, Buenos Aires,
Argentina; MACN) from litter submitted to a
Berlese funnel, taken in Chile, Reg. X:
Osorno, P.N. Puyehue, Aguas calientes,
sendero «El Pionero» (40º 44' 13.9''S-72º 18'
23.3''W). 70 m.bsl. This National Park is a
reserve of Valdivian forest (see fig. 1). This
Ecoregion is one of the most particular
environments of Chile, with a high degree of
endemism and one of the most diverse
biomes of the planet. Conservation
International identified this temperate region
as part of 25 places with most high value to
conserve biodiversity in the world level. It is
possible that this species has a extremely
localized population and this may be the
reason for this species to be included in the
Red List (SISG, 1996) as VuD2 (Vulnerable,
population is characterized by an acute
restriction in its area of occupancy, typically
less than 100 km2, or in the number of
locations, typically less than five). Other two
species of Oxyepoecus: O. bruchi Santschi,
1926 and O. daguerrei (Santschi, 1933) are
considered as endangered species too.
The specimen will be deposited at MACN.
I thank Dr. M. Ramirez for providing the
specimens of Oxyepoecus inquilinus, along
with innumerable additional specimens of
ants collected throughout Chile. Other
examined material: Oxyepoecus inquilinus,
1 worker, type material (IFML, Kusnezov coll).
Fig. 1. Record of O. inquilinus in the Valdivian
Temperate Forest, Chile.
Fig. 2. Distribution of Oxyepoecus inquilinus showing all known records of O. inquilinus
ACKNOWLEDGMENTS
This work was supported by a grant of CONICET, Argentina. To the reviewers for thier helpfull comments.
LITERATURE CITED
1. ALBUQUERQUE, N. N. & BRANDÃO, C. R. F. 2004.
A revision of the neotropical Solenopsidini ant
genus Oxyepoecus Santschi, 1926
(Hymenoptera: Formicidae: Myrmicinae). 1. The
vezenyii species group. Papeis Avulsos de
Zoologia 44 (4): 55-80.
2. FERNÁNDEZ, F. 2002. New ant records for Colombia
and South America (Hymenoptera: Formicidae)
Revista Colombiana de Entomología 28(2): 215.
3. KEMPF, W. W. 1974. A review of the Neotropical
ant genus Oxyepoecus Santschi. Studia
Entomologica (N.S.) 17: 471-512.
4. KUSNEZOV, N. 1952. Acerca e las hormigas
simbióticas del género Martia Forel. Acta
Zoológica Lilloana 10: 717-722.
5. SANTSCHI, F. 1926. Deux nouvelles fourmis parasites
de l'Argentine. Folia Myrmecologica et
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6. SOCIAL INSECTS SPECIALIST GROUP 1996.
Oxyepoecus inquilina. En: IUCN 2006. 2006
IUCN Red List of Threatened Species.
www.iucnredlist.org. Downloaded on 05
December 2006.
Recibido: 15-02-2007;
aceptado: 4-05-2007