Several pieces of evidence for the Belostomatidae and Nepidae pointing out to similar characters of the labium and other anatomical structures have been provided by Parsons [20, 25, 38], and they have served as basis for distinguishing the previous groups from the Gelastocoridae, Ochteridae, Aphelocheiridae, Naucoridae, and Notonectidae
Considering species found at higher altitudes (Group D), there is a clear dominance of Veliidae, Gerridae and Notonectidae
species, although Gelastocoridae and Belostomatidae are also represented.
Las familias mejor representadas fueron Gerridae con 12 especies (23%) y Veliidae con nueve especies ( 17%), seguida en su orden por Naucoridae con ocho (15%) y Notonectidae
con siete (13%) (Tabla 1).
Concentrations of mercury in Notonectidae
were significantly higher (P < 0.001) and concentrations of mercury in Hydrophilidae were significantly lower (P < 0.005) than all other taxa.
In this context, intraspecific differences in habitat use of the different instars have been observed, for example, in the predatory aquatic bug Notonecta hoffmani (Notonectidae
, reviewed by Morin 2011), the theraphosid Ephebopus murinus (Walckenaer, 1937) (Marshall & West, 2008), and the co-occurring ctenid wandering spiders Phoneutria fera Perty, 1833, and Phoneutria reidyi (F.O.P.-Cambridge, 1897) (Torres-Sanchez & Gasnier 2010).
25 Limoniidae Limoniidae sp.ind 3 Hemiptera Corixidae Sigara sp.ind 17 Notonectidae Notonectidae
sp.ind 1 Gerridae Gerridaesp.ind 2 Trichoptera 2 Familleind Trichoptera sp.ind 2 Basommatophora Physidae Physa sp.