Stilobezzia (Stilobezzia) rabelloi Lane, 1947

Torreias, S. R. S., Ferreira-Keppler, R. L. & Ronderos, M. M., 2013, Biting midges (Ceratopogonidae: Diptera) present in aquatic macrophytes from wetlands of Marchantaria Island, Iranduba, Central Amazonia, Brazil, Journal of Natural History 48 (1 - 2), pp. 109-122 : 119-120

Stilobezzia (Stilobezzia) rabelloi Lane

Stilobezzia (Stilobezzia) rabelloi Lane, 1947: 203 (male and female; Brazil), Borkent and Craig, 2001: 655 (redescription, pupa); Borkent and Spinelli, 2007: 87 (in Neotropical catalogue); Borkent and Grogan, 2009: 22 (in Nearctic catalogue, distribution); Grogan et al., 2010: 41 (Florida record); Borkent, 2012: 138 (online catalogue).

Distribution

Argentina, Brazil (Mato Grosso, Rio de Janeiro) , USA (Maryland to Louisiana and Florida) .

Material examined

Brazil, Amazonas , Iranduba , Ilha da Marchantaria, Lago Grande, E. crassipes , 4 April 2011, Torreias col., 1 male and 1 female (reared in laboratory, with pupal exuviae) .

Comments

This species is widely distributed through the Americas. Immatures were collected from between the leaves of E. crassipes . Stilobezzia rabelloi present body bristles and with elongated processes on their upper side, which help with balance and the insertion of spiky breathing organs into the macrophytes aerenchyma to obtain oxygen ( Borkent and Craig 2001). This is a new record of this species from the Amazonas State.

For ecological records, the collected genera were sampled in floating vegetation in lentic waters. The pH, temperature and conductivity were respectively: 9.76, 29.8 ◦ C and 243.8 µS / cm. In this system the immatures were probably feeding on organic debris accumulated in the roots of aquatic plants. According to Conserva et al. (2008) aquatic macrophytes are considered good indicators of biological diversity in permanent or temporary wetland, so composing the landscape diversity in floodplain areas.

This system is characterized as raising aquatic productivity, which enhances the development of aquatic entomofauna; in other words, the higher the diversity of aquatic macrophytes, the bigger the number of available habitats – considerably raising the richness and abundance of insects and other macroinvertebrates ( Junk 1973; Conserva et al. 2008). It is mainly immature Ceratopogonidae that occur in multiple trophic webs, and form an important part of aquatic ecosystems, in terms of abundance and composition of species.

Even though there is a lack of information regarding the proper identification of some taxa, the information gathered on Ceratopogonidae , with a better taxonomic resolution (e.g. genera or morphotypes), is important to the recognition of new potential habitats that contribute to ontogenetic development, making it possible to carry out bionomic, ecological and taxonomic studies in these areas.

Although knowledge associating immature forms with the adult stages was lacking, the present study provides evidence that aquatic macrophytes are important breeding places that maintain and give balance to ceratofaunal biodiversity in wetland lakes. Also, they can be regarded as separate units, because the appearance of lakes and macrophytes is directly connected to the periodic flooding of rivers in the region, causing the occurrence of certain organisms to be ephemeral, and consequently creating possible sites of endemicity and specificities.