Protallagma

Hunger, Holger & Schiel, Franz-Josef, 2012, Description of Protallagma hoffmanni sp. nov. from the Peruvian Andes (Odonata: Coenagrionidae), including description of its larva, Zootaxa 3202, pp. 28-50 : 48-49

Ecology of Protallagma (cf.) titicacae

Garrison et al. (2010) state: “Habitat: Lakes, ponds, pools, and seeps in high altitude Andean plateau, where they can be seen in swarms and constitute the only zygopteran present.” Hoffmann (in: Corbet 1999) describes habitats at 4,730 m in the treeless Janca of the Peruvian Andes in which resident populations were found. The species seems to occur regularly in Puna type regions in protected landscapes in natural depressions characterized by small forests of Polylepis trees. Furthermore, water and soil were often warmed by thermal streams. Adults of Protallagma titicacae flew close to the ground, and when clouds obscured the sun the damselfly promptly took cover in tufts of grass where they were sheltered from wind and could absorb warmth from the heated ground. Further information on the ecology of Protallagma titicacae is sparse and restricted to sites in Chile and Argentina. Jurzitza (1989) states that P. titicacae was found in Chile in andine salt lakes (some of them above 4,200 m) and river shore. Bulla (1972) describes two habitats where he found larvae. The first was a small creek (maximum width 1 m, maximum depth 60 cm but often much shallower) near Copacabana (La Paz, Bolivia). Here, the larvae were found in both slow and fast flowing zones and were always associated with the dense vegetation growing in the creek. At the time of collection of the larvae (early January) the location was characterized by strong diurnal fluctuations of air temperature (25°C during the day and strong snow fall at night). The second larval habitat was a runnel discharging into the Río Vilcanota at San Jerónimo 5 km south of Cuzco ( Peru). This runnel formed at its mouth an inundated swamp zone (maximum water depth: 15 cm) with abundant vascular plant vegetation wherein the larvae were found. Bulla (1974) states that P. titicacae was known in Argentina only from Abra Pampa, Jujuy, 4,000 m a.s.l., and was the zygopteran living at the highest altitudes in Argentina.

Distribution, ecology, and biology of Protallagma hoffmanni

So far, Protallagma hoffmanni has been recorded only from one short rivulet discharging into Laguna Querococha. During our field trip from February 13 to 20, 2007, we sampled several other ponds, riverine areas, and fens, and collected specimens of Oxyallagma dissidens at several locations, but we did not record Protallagma spp. at any of these sites. Therefore, collecting of P. hoffmanni at Laguna Querococha has to be restricted. We want to stress that official permits have to be issued before any collecting or other activities.

Some data were gathered by Joachim Hoffmann at Laguna Querococha itself at the exact date and time when we collected the specimens on February 18, 2007, 11:50: surface water temperature 14.0°C; pH 7.05, conductivity 50 S/m. However, we did not take measurements in the runnel where we found the larvae and imagos of P. h o f f - manni close to the mouth at Laguna Querococha. This short, winding runnel was characterised by shallow, slowflowing water with sediment dominated by dark detritus. Surrounding grassy vegetation was low, so there was no shade and insolation was very intense. Thus we suppose that the shallow water heated up, providing for a warm microclimate which is important at an altitude of almost 4,000 m a.s.l.

The 19 larvae collected belonged to four stadia, with the four biggest larvae in the apparent FO stadium. The four different size-classes suggest a semivoltine development probably lasting two to three years.

We did not observe reproductive activity. As in most species of Odonata males tend to concentrate at reproductive habitats, whereas females spend much time at a distance and only move to the reproductive habitats to mate and oviposit, this might indicate that neither males nor females usually move away from this runnel because other suitable habitats are extremely rare. We found almost all of them perched in the tall Ichu grass vegetation in the vicinity of the runnel.

We noted that a high percentage of the specimens taken (7 out of 8 males and 5 out of 9 females) were parasitized by red water mites (especially the underside of the thorax and first abdominal segments; in males around the secondary genitalia).