Diversity of true bugs from Iguazú National Park , Argentina

We list all taxa identified to species level, belonging to 18 families of Heteroptera: Reduviidae (63 species), Tingidae (9 species), Alydidae (6 species), Coreidae (39 species), Rhopalidae (11 species), Largidae (1 species), Pyrrhocoridae (4 species), Acanthosomatidae (1 species), Pentatomidae (58 species), Scutelleridae (3 species), Berytidae (1 species), Blissidae (5 species), Colobathristidae (2 species), Cymidae (1 species), Ninidae (1 species), Lygaeidae (6 species), Pachygronthidae (1 species), and Rhyparochromidae (13 species). Among the listed species, 13 are new country records belonging to the families Reduviidae, Tingidae, Pentatomidae, Coreidae, and Alydidae.


Introduction
One of the main concerns in the scientific community is the effect of climate change in the planet, how species will respond to the actual global warming and how it will affect the biodiversity.Even though insects have colonized almost every niche and are the most important group in terms of specific diversity they have been largely ignored in studies dealing with conservation strategies.These studies used to be more focused on charismatic fauna (Stewart 2012), though nowadays more attention is starting to be payed to insects as they have proven to be very good sentinels for environmental and habitat change (New 2012).Insects live in complex ecological webs, connected to other taxa that could be competitors, mutualist partners, food plants and natural enemies.The use of a particular species as a flagship to stimulate the development of conservation interest have been practical, however for a more thorough conservation plan, wider perspectives, emphasizing guilds, assemblages, communities, biotopes from local sites to broad landscapes should be taken into account (New 2012).
The Iguazú National Park is located between 25°31ʹ S to 25°43ʹ S and 054°08ʹ W to 054°32ʹ W in the Iguazú Department in Misiones Province, Argentina.Its northern limit is the Iguazú River which forms the Iguazú Falls, the largest waterfalls system in the world and an UNESCO World Natural Heritage Site since 1984.The meaning of the word Iguazú, comes from the Guarani with "y" meaning "water", and "ûasú" meaning "big", thus "Big Waters" for the native people.The Park protects 67,720 ha of the Paraná Forest, constituting a significant remnant of the Atlantic Forest, one of the largest and most threatened tropical rainforests in the world (Tabarelli et al. 2010).It is the most diverse area in Argentina with ca.3000 of vascular plants forming a stratified forest that harbors a diverse fauna (Chebez 2005).This National Park is connected to other conservation areas, to the north it limits with the do Iguaçu National Park (170,000 ha) in Brazil, and to the southeast to the Urugua-í Provincial Park (87,000 ha) and the Private Reserve San Jorge, Salto Yasý and Perobal (20,000 ha), and other nine smaller protected areas (ca 7000 ha) (Chebez 2005).These protected areas are part of the Green Corridor of Misiones Province guaranteeing the connectivity between protected areas, thus allowing the continuity of the natural processes of migration and seasonal displacements of the wild fauna, and those related to the dispersal and natural replacement of the wild flora of the native forests (Law XVI Nº 60 from Provincial Juridical Digest).
Studying the insect fauna and monitoring selected groups is crucial to accompanying conservation efforts (New 2012), and to be able to evaluate and/or forecast the impact of climate change.Knowing the value of the biodiversity and the role that insects play in nature, we aim to study the biodiversity of terrestrial Heteroptera inhabiting in the Iguazú National Park in Misiones Province, Argentina.

Methods
Two field trips of about 10 days each were conducted to the Iguazú National Park (Fig. 1), during October to November 2012 and December 2013.Permits to collect material were provided by Administración de Parques Nacionales (NEA 310 rnv2).Most of the specimens were collected using sweeping and beating nets; complementary collection was done by hand directly on the ground and visual inspection at light traps.Additional specimens were collected using Van Someren-Rydon traps with different attractants; this trap consists of a tube with a height of 30 cm, that it is closed at the top and with a plate attached at the bottom, where a "bait" is placed to attract insects.The bait can be fish, rotten fruit or a chemical attractant.The trap is hanged at different levels of the forest (2 m, 3 m, 4 m).Specimens were preserved in 96% ethanol, then mounted in the lab, and examined under stereomicroscope.
To confirm the identification of some specimens, the genital capsule of males and genital segments of females were dissected and cleared with a saturated potassium hydroxide solution for observation; dissected genitalia were preserved in microvials with glycerin.The specimens were deposited in the Museo de La Plata, Buenos Aires, Argentina (MLP).We also studied the entomological collections of Museo Argentino de Ciencias Naturales, Buenos Aires, Argentina (MACN), Instituto Miguel Lillo, Tucumán, Argentina (IMLA), and MLP.In the list we also include the species that were previously mentioned from the area even though no specimens were examined.In the cases of the species of Coreoidea and Lygaeoidea a LSID was added, linking with the Species File website of each taxa (Dellapé and Henry, CoreoideaSF Team).Additional specimens of the families Anthocoridae, Nabidae, Miridae, and Thyreocoridae that were collected and not included in the present paper were deposited in MLP.The known distribution of the species refers to the political division of Argentina into provinces; other countries where the species have been recorded in the literature are mentioned.
Remarks.Although this species is similar to B. nanus, the specimens we have examined are much larger (18.275 mm), with less prominent eyes and shorter antenniferous tubercles.According to Carpintero (1980) B. nanus is a much smaller species (15.12 mm), with much more protruding eyes and longer antenniferous tubercles.Carpintero, 1980 Distribution.Argentina: Misiones: P.N.Iguazú (Carpintero 1980).
Remarks.New country record.
Graptocleptes sanguineiventris can be recognized by the large size of the eyes extending to the ventral region of the head, the short post-antennal tubercle, the abundant seta on the gular region, and the reddish abdomen.This species shows the common black and reddish general coloration, with the hemelytra black or dark brown, with a yellow spot on the external and mid-distal portions of the corium, and the mid-and hind femora with a yellow annulus at the middle.These features mimic some Braconidae and Ichneumonidae (Gil-Santana et al. 2013), a characteristic extended among certain genera of Reduviidae as Graptocleptes Stål, Hiranetis Spinola and Parahiranetis Gil-Santana.The limits of these three genera are not clear and a comprehensive revision is needed (Gil-Santana et al. 2015).
Remarks.New country record.This species can be distinguished from the other species of the genus by its mostly blackish hemelytra, and the yellowish basal region of the median and posterior femora (Coscarón 1994).Lent, 1955 Distribution.Argentina: Corrientes and Misiones: Iguazú (Lent 1955, Lent andJurberg 1967); Brazil and Paraguay (Lent 1955).
Remarks.First record for Misiones province.This species can be distinguished by the small size (less than 20 mm); the mostly black pronotum and corium, and the dark abdominal sterna (Lent and Wygodzinsky 1956).
Remarks.First record for Misiones province.This species can be distinguished by the completely black scutellum, and the concolorous veins of hemelytra (Lent and Wygodzinsky 1956).
Remarks.First record for Misiones province.This species can be distinguished by the general red coloration of the body and the hemelytra with three completely closed discal cells (McAtee and Malloch 1923).The specimen we examine fits with the specific diagnosis given by McAtee and Malloch (1923) where the posterior pronotal spines are short and acute.
Remarks.New country record.This species can be distinguished by the unarmed lateral margins of the pronotum; pronotum twice longer than head, and over twice as long as wide; the post-ocular region twice as long as the pre-ocular margin of head (Barber 1930).Giacchi, 1970 Distribution.Argentina: Buenos Aires, Chaco, Entre Ríos, Mendoza, Misiones, Santa Fe, and Tucumán; Bolivia, Brazil, Paraguay, and Uruguay (Giacchi 1977).
Remarks.First record for Misiones province.
Remarks.First record for Misiones province.
Material examined.Remarks.New country record.This species can be distinguished by its five cephalic spines, its short hood not reaching the anterior margin of the eyes, its pronotum three carinated, the paranota carinae like, the hemelytra with dark brown "X" pattern and its costal area with one row of rectangular areolae.
Remarks.First record for Misiones province.

Chariesterini
Chariesterus armatus (Thunberg, 1825)  Remarks.First record for Misiones province.This species can be distinguished from the other species of the genus by the humeral spines shorter and not arcuate but directed laterally and slightly upward rather than forward, the tomentum of the pronotum interspersed with erect setae, and the abdominal dorsum rosaceous to sanguineous in the middle and black at base and apex (Ruckes 1955).Brailovsky, 1986 (Fig. 27 Remarks.First record for Misiones province.This species belongs to the vacillans group characterized by having a slender body, acutely projecting humeral angles, and black or reddish brown claval margin.Scamurius marianae can be distinguished by the shape of the postero-ventral edge of the pygophore with a shorter medial notch delimited laterally by two monticular prominences adjacent to the midline to the sides of which there are two longer processes projecting (Brailovsky 1986).Stål, 1860 (Fig. 28 Remarks.First record for Misiones province.This species can be distinguished by its large size, the antennae shorter than the total body length, the distiflagellomere longer and more robust, and the spermatheca filiform and rolled up (Brailovsky 1988).
Material examined.1♀, 11-XII-2008, Zamudio & Colleselli Gómez de Olivera colls., PNI0367 (MLP); 1♀, Iguazú, PNI0368 (MLP).(Westwood, 1842) Barber, 1926 (Fig. 29 Remarks.New record for Misiones province This species belongs to the inarmata group, which is characterized by the absence of a spine in the antenniferous tubercles.Catorhintha divergens can be easily distinguished by the combination of the following characters: the humeral angles of the pronotum expanded and acute, the scape ocher with a black outer band, thorax ventrally immaculate and with the dorsal segments of the abdomen bright orange with a reddish brown fascia media (Brailovsky and García 1987).Brailovsky & García, 1987 (Fig. 30 Remarks.New country record.This species can be distinguished by the external spine of the antenniferous tubercle twisted over the base of scapus and the immaculate abdominal sterna (Brailovsky and Garcia 1987).Berg, 1892 http://lsid.speciesfile.org/urn:lsid:Coreoidea.speciesfile.org:TaxonName:454308

Cebrenis cauta
Distribution.Argentina: Catamarca, Corrientes, Mendoza, and Misiones; Bolivia, Brazil, Grenada, Paraguay, Peru, Trinidad, Tobago, andVenezuela (Brailovsky 1995, Packauskas 2010).Zicca annulata (Burmeister, 1835)  Remarks.New country record.This species can be easily distinguished from the other species of the genus by the armed anterior and medial femora, the obtuse humeral angles; the orange brown with yellowish margins scutellum; and the yellowish claval vein and adjacent areas of hemelytra (Brailovsky and Barrera 1986).Remarks.First record for Misiones province.This species can be distinguished from the other species of the genus by the unicolorous basi and distiflagellomere, the unicolorous hind tibiae and bicolorous hind femur that is mostly yellow with the blackish apical third, the glabrous pronotal disk, and propleuron, mesopleuron and metapleuron with a large black discoidal spot (Brailovsky and Barrera 2007).Berg, 1883 (Fig. 33
Material examined.
Remarks.This species can be distinguished by its four segmented antennae, with the pedicel very long, at least three times longer than the scape; and the general color brownish, coppery, with the pronotum processes and hemelytra veins paler (Berg 1892, Grazia et al 2015).
Remarks.New country record.This species can be easily distinguished from the other species of the genus by the shape of the pygophore in the males and the first gonocoxae in the females (Thomas and Yonke 1990).Thomas, 1990 Distribution.Argentina: Misiones: Iguazú (Dellapé et al. 2015a); Brazil (Thomas and Yonke 1990).Distant, 1893 Distribution.Argentina: Chubut and Misiones (Dellapé et al. 2015a): from Panama to northern Argentina (Brailovsky and Rolston 1986).
Remarks.New country record.This species can be easily distinguished from the other species of the genus by the abdominal spine reaching the anterior limit of the mesocoxae, the lateral jugal margins slightly or not edged in black, and the shape of the first gonocoxae in females (Schwertner and Grazia 2007).Rolston, 1983 Distribution.Argentina: Buenos Aires and Misiones; Brazil and (Rolston 1983, Schwertner and Grazia 2007, Carpintero and de Biase 2011).
Remarks.First record for Misiones province.
In this species the posterior margin of the corium is strongly sinuous, and the lateral angles are produced.In males the posterior dorsal side of the proctiger lack distinct spines, and the dorsolateral parameral processes from caudal view are inclined dorsad and rounded at the apex.In females the length of the first gonocoxae from base at meson to posterior apex is less than 1.5 mm, and the length of the second gonocoxae at meson less than 0.9 mm (Eger 1978).(Mayr, 1864) Distribution.Argentina: Corrientes and Misiones; Bolivia, Brazil, and Paraguay (Dellapé et al. 2015b).
Remarks.First record for Misiones province.This species can be distinguished by the coloration pattern with longitudinal stripes (Eger et al. 2015).
Remarks.First record for Misiones province.
Members of this group are small brownish to yellow and coarsely punctate insects that closely resemble the seeds of the sedges upon which they live.Cymodema breviceps is the only species of the family recorded from Argentina.
Remarks.First record for Misiones province.
The orange head with a dark tylus and the interocelar space with two dark stripes, together with the coloration pattern of pronotum with yellow margins and orange tonalities, allow to separate this species from the others in the genus.
Remarks.First record for Misiones province.This species can be distinguished by the yellow trochanters and by the dark hemelytra with yellow borders, interrupted after the middle of the costal margin and over the middle of the inner margin.

Discussion
In the present contribution we listed 225 species from Iguazú National Park, 109 species were collected in 2011-2013 field trips using sweeping and beating nets and light trap, this number is increased to 131 species if we also consider the Van Someren-Rydon traps of the 2008 collections.The three most diverse families in our inventory were Reduviidae with 63 species, Coreidae with 39 species and Pentatomidae with 58 species; if we only consider the 2008 and 2011-2013 collections, these numbers drop down to 17, 27 and 41, respectively, representing around 26%, 69%, and 70% of the total number of the inventoried species of each family.The low percentage of Reduviidae collected shows the low efficiency of nets to sample this family, and the low performance of the light trap during the 2011-2013 collections; as pointed out by Lucas et al. (2016), light traps require certain weather conditions to perform better, the daily maximum temperature and the rainfall are negatively correlated with the abundance of reduviids collected at light traps in forest areas.In the case of Coreidae, only 8 species were collected with nets, resulting the Van Someren-Rydon traps a much more efficient method to sample this family.On the other hand, our results indicate that beating and sweeping nets are an efficient method to sample pentatomids with 40 species collected during the 2011-2013 trips.
Our inventory includes 95 species recorded only from the literature or from older specimens in collections, the absence of species in our samples could be explained by the different efficiency and effort of each sampling method used, but also by chance.Another possible explanation is that these species are not actually present in the area.Distributional range shift is the most frequently reported response of insects to climate change (Parmesan, 2001, Musolin andFujisaki, 2006).This could also be true for the new records found from the area; Musolin (2007) observed that the expansion of distribution range of individual Heteroptera species can enrich local faunas, especially at higher latitudes, and that climate change has accelerated this process.
Although this inventory is far from complete, as evidenced by the comparison of the sources used to build it, and because we do not include all families (some diverse families such as Anthocoridae, Miridae, Thyreocoridae, etc), it is important to highlight that it is the largest inventory of terrestrial Heteroptera from an Argentine protected area.Another important fact of this inventory is that we present 13 new country records among the 18 studied families.
In the context of the actual climate change and its effect on biodiversity, we believe this could be the starting point for future analysis, in particular monitoring the state of conservation of the protected area.In this case, the best choice could be to select a taxon (e.g.family) and design an efficient protocol to sample the area in a long term period.