Grasshoppers of the Andes: new Melanoplinae and Gomphocerinae taxa (Insecta, Orthoptera, Acrididae) from Huascarán National Park and Callejón de Huaylas, Ancash, Peru

ABSTRACT The grasshopper fauna from Huascarán National Park and the valleys of “Callejón de Conchucos” and “Callejón de Huaylas”, Perú, has been sampled during two surveys of the area in 2004 and 2008. In this paper, two new genera (Tiyantiyana n. gen. and Huaylasacris n. gen.) and six new species collected during the surveys are described: Tiyantiyana sunipenis n. gen, n. sp., Huaylasacris maxicerci n. gen, n. sp., Maeacris chilikuti n. sp., M. saytu n. sp., M. ayasqa n. sp. of the subfamily Melanoplinae and Orphulella chumpi n. sp. of the subfamily Gomphocerinae. Previous records on the highland grasshoppers of the Peruvian Andes were almost nonexistent. The new acridids described here were collected at the high-altitude puna grassland, between 3182 and 4660 m a.s.l. Puna is one of the most heavily modified natural regions of Peru. Since grasshoppers are a useful group for bioindication, it is important to acquire knowledge on their diversity in such environmental conditions. This paper includes many embedded links to images of type specimens, maps based on geo-referenced specimen data, and keys to species, all available at Orthoptera Species File Online (http://orthoptera.speciesfile.org).


INTRODUCTION
The Huascarán National Park (3400 km2) covers the length of the Cordillera Blanca range in the central Andes of Peru. Extending 158 km from north to south and 20 km from the valleys of "Callejón de Conchucos" in the east to the "Callejón de Huaylas" in the west, the park contains 60 peaks with altitudes surpassing 5700 m, the highest being Huascarán at 6768 m. Most of the terrain below 4800 m is characterized by high altitude grassland (puna) with Polylepis forest remnants located on the upper, inner valley slopes (Byers 2000). The puna is a unique ecosystem that clearly shows the struggle of plant and animal life against extreme cold and solar radiation (Vuilleumier & Monasterio 1987). Human activities severely limit biodiversity in this ecosystem by threatening the survival of many yet unnamed species, while global warming causes retraction and sometimes disappearance of these montane life zones identified as highest priority for biodiversity conservation (Dinerstein et al. 1995;Vilimek et al. 2005;Bury et al. 2011). The grasshopper fauna from these highlands is represented mostly by two Acridoidea families (Tristiridae Rehn, 1906 and Acrididae MacLeay, 1821) that could be used, besides other sensitive groups (Proscopioidea), as bio-indicators for the condition of the puna ecosystem.
The Cordillera Blanca forms a mountain island above the surrounding valleys where the use of inappropriate agriculture and livestock methods combined with high population growth has destroyed the original vegetation cover, leaving few remnants of native forest and many invasive exotics (Bartle 1993;Young & Lipton 2006;Young 2009). The biodiversity crisis that affects most regions of the globe makes descriptions of new taxa an urgent matter. Describing them provides not only a record of their existence, but also scientific rationale for the protection of areas rich in endemic organisms with interesting life histories. The main objective of this ZOOSYSTEMA • 2011 • 33 (4) paper is the description of new taxa of Acrididae and to report on the grasshopper fauna of Huascarán National Park and its surroundings.

MATERIAL AND METHODS
Terminology for external morphology and male genitalia follows Otte (1981) and Amédégnato (1976), respectively. Measurements are given in millimeters; body length is measured from the apex of fastigium to the apex of hind femur. The specimens measured correspond to the material designated as holotypes, allotypes, paratypes and other material examined.
Museum specimens were relaxed in a humid chamber and the abdominal terminalia were moistened with ammonia (Cigliano & Lange 2007). Genitalia were then pulled from the body using a finely hooked pin, cleared in potassium hydroxide, and stored in glycerine.
Descriptions of Melanoplinae species are mostly based on male specimens because many females are difficult to discriminate and thus the identification is usually done by association with males collected at the same time and place.
Photographs of the phallic complex were taken with a Micrometrics digital camera attached to a Nikon stereomicroscope. Photographs of the habitus were captured with a Canon Eos Rebel digital camera. The program Combine Z5.3 (Hadley 2006) was used for focus stacking (a technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field than any of the individual source images). Illustrations were made as pencil sketches using a camera lucida.
Specimens examined are deposited at Museo de La Plata, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Argentina (MLPA) and at the Muséum national d'Histoire naturelle, Paris (MNHN).
The pdf edition of this paper has been formatted with embedded links to images of type specimens, keys, maps based on geo referenced specimen data in the Orthoptera Species File (OSF) online (http:// orthoptera.speciesfile.org) (Eades et al. 2011 descripTion Small sized apterous insects. Body colour highly variable with multiple short carinulae on tegument.

Females
Similar to males, but more robust and with the pronotum constricted at the middle. Tegument with clearly indicated carinulae (Fig. 4B). Head with fastigium more prominent; eyes subtrigonal (Figs 1F; 4B). Ovipositor valves strong and long, with serrate margins (Fig. 1H).
relATionships Despite the lack of the spur on the prosternum (that may be related to the apterism condition), Tiyantiyana n. gen. shares the remaining diagnostic characters of the subfamily Melanoplinae: frons convex, profile of face and fastigium united in the same curve; male abdominal terminalia swollen and upcurved, palium coriaceous; male phallic complex with the middle part of the endophallic sclerites constituted by one dorso-lateral piece; cingulum with arch clearly developed. Based on the morphological evidence it was not possible to assign the genus to any of the three tribes described for the South American Melanoplinae (Amédégnato et al. 2003;Carbonell et al. 2006): Jivarini Hebard, 1924, Dichroplini Rehn & Randell, 1963and Parascopini Ronderos, 1983. However, molecular analyses currently underway have shown that Tiyantiyana n. gen. is grouped with the remaining Andean melanoplines genera (unpublished observations). eTyMology. -"Suni" means long in Quechua native language referring to the length of the valves of the aedeagus.
hAbiTAT. -According to our observations, Tiyantiyana sunipenis n. gen., n. sp. inhabits puna grassland areas with bunchgrasses of Festuca and Poa forming tussocks. Spaces around the tussocks filled by numerous cushion and rosette herbs, including non-tussock-forming grasses and sedges, prostrate or low-growing forbs.
diAgnosis. -Very small species (from 9 mm in the smaller males to 15.5 mm in the largest females), with variable ground coloration mostly in females. descripTion

Males
Body dorsally brown-grey, head brown with grey face. Lateral lobes of pronotum green. Hind femur with dorsal marginal area green, outer face dark brown with two transverse whitish coloured bands; internal face whitish with two transverse dark brown bands; ventral area of hind femur and hind tibiae purple or pinkish. Phallic complex (Figs 1I-M; 4C-E): valves of aedeagus very long, protruding beneath the pallium, highly surpassing the level of the epiproct, apex bent downwards; sheath of aedeagus covering ⅔ of the valves of aedeagus with numerous spines; arch of cingulum large. Epiphallus with lophi widely developed horizontally and reduced anchorae. Measurements (in mm): body length to end of hind femur: 10.26 (9-11.5); hind femur length: 5.95 (5.5-6.5).

Females
Similar to males, but more robust and with the pronotum constricted at the middle and with the carinulae on tegument clearly indicated (Fig. 1G). Head with fastigium more prominent; eyes subtrigonal (Figs 1F; 4B). Ovipositor valves strong and long, with serrate margins (Fig. 1H). Body colour highly variable: ground colour green, brown or dark purple almost black; with two longitudinal cream bands running along the lateral carinae of the pronotum, the meso and metanota and along abdominal tergites, in some specimens limited by dark brown bands on the head. Body ventrally purple. Hind femora with dorsal area homogeneously green or with two dark brown cross bands, internal face and ventral area red-orange or purple. Hind tibiae red-orange or purple.
diAgnosis. -Among Jivarini, Maeacris is characterized by the hind tibiae with the external apical spine reduced or absent.
redescripTion Small sized apterous insects. Head conical with subtrigonal, flat eyes; face slanted; fastigium slightly prominent, weakly grooved dorsally, and rounded at the joint of frontal costa (Figs 2A  eTyMology. -"Ch'ilikuti" means small in native Quechua language and it refers to the smaller size of this species compared to Maeacris aptera. disTribuTion. -Peru, Ancash (Fig. 10).
hAbiTAT. -In puna grassland areas with bunchgrasses of Festuca and Poa forming tussocks. Spaces around the tussocks filled by numerous cushion and rosette herbs, including non-tussock-forming grasses and sedges, prostrate or low-growing forbs.

Males
In addition to the features of the genus, body ground colour variable; both sexes show green-brown variation, with some specimens being mainly greenish on top of the body and others brownish. Body with two longitudinal light coloured bands (cream in green morphs; grey-brownish in brown morphs) extending from the fastigium along the body dorsally. Pronotal lobes with dark green or dark brown post-ocular band, limited by a longitudinal cream stripe. Hind femur with dorsal area brownish (brown morphs) or greenish (green morphs), outer face brown, ventral area cream or yellowish, inner face brownish at upper half and cream at bottom half; hind tibiae light green to cream. Venter of abdomen cream. In some females, the ventral area of hind femur and hind tibia is reddish. Hind tibia without external apical spine. Male epiproct triangular and wider than long, with a pair of distal tubercles (Fig. 2C). Phallic complex (Figs 2G-K; 6A-C): cingulum widely developed dorsally; arch of cingulum bilobed; valves of aedeagus up curved, obliquely truncated in dorsal view, concave in ventral view; sheath of aedeagus with median deep excision and with a pair of basal lobes.

Females
Similar to males (Fig. 2E, F), but larger; head with fastigium more prominent; eyes subtrigonal and ovipositor valves long, slender, without pre-apical tooth.

Maeacris saytu
eTyMology. -"Sayt'u" means long, slender, rectangular shape in native Quechua language, and it refers to the shape of the valves of the aedeagus.
disTribuTion And hAbiTAT. -Same as described for Maeacris chilikuti n. sp. (Fig. 10). descripTion Males Similar to those of Maeacris chilikuti n. sp. from which they can only be distinguished by the following characters of the phallic complex: aedeagal valves straight in lateral view (Fig. 2L), with blunt apex (Fig. 2N); arch of cingulum entire (Fig. 2M); sheath of aedeagus with longitudinal median excision without basal lobes.

Females
Similar to males but with fastigium more prominent; eyes subtrigonal; ovipositor valves long, slender, without pre-apical tooth.

Females
Similar to males but with fastigium more prominent; eyes subtrigonal; ovipositor valves long, slender, without pre-apical tooth.
Tribe dichroplini Rehn J. A. G. & Randell, 1963 Genus Huaylasacris n. gen.  diAgnosis. -Easily identified from any other genera of Dichroplini by the unique shape of the male cerci widely developed, embracing the paraprocts (Fig. 3C, D) and the large lophi of the epiphallus (Figs 3I; 7E). descripTion
relATionships Based on the characteristics of the external morphology and phallic complex, Huaylasacris n. gen. seems to be related to the Dichroplini genus Chibchacris Hebard, 1923 from which it is distinguished by the shape of the tegmina not touching each other dorsally, the pronotum with hind margin emarginate, male cerci embracing the paraprocts and differences in the phallic complex.
(Figs 3A-L; 7; 10) hAbiTAT. -In puna grassland areas with a resilient mat of high grass and tussock species of Festuca, Calamagrostis and Stipa with occasional islands of scrubby elfin woodland of Polylepis (queñua) and along the grassland valleys in areas with traditional subsistence farming.

Males
In addition to the features of the genus, body ground colour green, chestnut or burgundy with a wide cream mid-longitudinal dorsal stripe on the abdomen, on some specimens this stripe continues on the pronotum. Tegmina with mid-dorsal portion cream. Hind femur with the dorsal marginal area cream, ventral marginal area yellow. Venter of abdomen yellow or burgundy or bright orange. Hind tibiae orange or purple. Measurements (in mm): body length to end of hind femur: 12.5 (11.5-13.5); hind femur length: 7.41 (6. .

Females
Similar to males (Figs 3E, F; 7B), body ground colour mostly chestnut or burgundy with a whitish stripe on dorsum of body occurring as in males. Pronotum constricted at the middle; eyes sub-trigonal; ovipositor valves short and robust with acute apex.
hAbiTAT. -As with most species of the genus, Orphulella chumpi n. sp. is found in grassy areas in the valley of "Callejón de Huaylas". descripTion Males Body colour light brown on top, brown-gray on sides and brown ventrally. Hind femora with few dark markings on the outer faces. Hind knees dark brown. Hind tibia brown. Lateral foveolae of the fastigium barely visible from above. Antennae short and slightly ensiform, light brown proximally and dark brown distally. Pronotum with a black band on lateral lobes, just beneath the lateral carinae (Fig. 8A). Posterior margin of pronotal disk angulate, slightly rounded. Mid-longitudinal carina on pronotum prominent and cream colour; lateral carinae distinct throughout their length, nearly parallel on the prozona, constricted in center, diverging on the metazona and cut by one transverse sulcus (Fig. 8C). Hind femora in males with stridulatory pegs. Wing length barely reaching the end of the abdomen (Fig. 8A). Like other gomphocerines, species in the genus Orphulella do not show diagnostic characters in the phallic complex (Fig. 8E, F).   Measurements (in mm): body length to end of hind femur: 11; hind femur length: 6.8.
Females (Fig. 8B, D) Similar to males, with body dorsally light brown or pale green and brown on sides. One female with sides of body and abdomen somewhat dark mottled and with two black stripes on top of head.

reMArks
A modified key to the South American species of Orphulella based on Otte's key (1979) (2010) based on COI sequences from specimens reported herein and from material of T. pallidipennis from Argentina and the USA (in total 28 individuals) showed that the specimens from the surveyed region constitute a different genetically haplotype which is more divergent than the specimens from Argentina (Mendoza, San Luis provinces). Future analyses on larger series of specimens of Trimerotropis pallidipennis and Trimerotropis andeana all throughout its distribution area is needed to clarify the specific and subspecific status of these taxa.

DISCUSSION
So far, there is no comprehensive study of the grasshopper fauna of Peru, and there are only few records of highland species of the Peruvian Andes. In total, eight species of Acrididoidea MacLeay, 1821 were collected during the two surveys to Huascarán National Park and the wide valleys of the "Callejón de Conchucos" and the "Callejón de Huaylas". Seven of these eight species collected are new to science, including the recently described Pediella ancashensis (Cigliano et al. 2010). These findings highlight how little we know on the grasshopper fauna from these highlands. The new acridids were collected in the puna formation in altitudes of 3180 to 4660 meters. Puna is a dry ecosys-ZOOSYSTEMA • 2011 • 33 (4) tem (Vuilleumier & Monasterio 1987;Luteyn et al. 1992), and it is one of the most heavily altered natural regions of Peru. At present, degradation of habitats is mostly related to overgrazing and contamination from mining (Davis et al. 1997). Puna is officially protected in three national parks in Peru, including Huascarán National Park, where the vegetation consists almost exclusively of this formation. The grasshopper fauna from the highlands of the Andes is represented mostly by two families: Acrididae and Tristiridae. Contrary to what was expected ahead of the surveys, no tristirid species was found in the region. This family endemic to South America is known to occur along the Andes of Chile, Argentina and Peru (Cigliano 1989a, b;Cigliano & Lange 2000), with one species, Punacris peruviana (Saussure, 1888), being distributed in the Peruvian puna. Six of the eight species registered in the surveyed region are wingless or brachypterous melanoplines. The remaining two species belong to Gomphocerinae, tribe Orphulellini (O. chumpi n. sp.), and Oedipodinae (T. andeana). The Melanoplinae is the largest subfamily of grasshoppers in the New World, inhabiting a broad range of habitats from Alaska to Patagonia (Cigliano & Otte 2003;Cigliano et al. 2000). Melanoplines can be excellent monitors of landscape use, as they are ecologically sensitive and yet sufficiently mobile and abundant to serve as bioindicators (Samways 1997(Samways , 2005. Grasshoppers are a useful group for bioindication because of their sharp reaction to climatic factors and ecological sensitiveness (Samways 1997(Samways , 2005Bazelet 2011). With the help of indicator species, it is possible to measure the quality of certain habitats. The usefulness of Orthoptera to evaluate the quality of high-altitude grasslands could already been proved by studies at Mount Kilimanjaro in Tanzania (Hemp & Hemp 2003;Hemp 2009).
The Andes are characterized by a long list of outstanding features including numerous endemic organisms with interesting life histories. We were only able to scratch the diversity of grasshoppers in a relatively small area. An understanding of critical issues (what species exist where, and where conservation efforts should be focused) is hampered by the scale and complexity of the biodiversity in the Andes. We hope that the new taxa described here will serve as inspiration for research on this biodiversity and its conservation.