Myriapods constitute important edaphic macrofauna taxa which dwell in different trophic levels and influence the dynamics of these environments. This study evaluated the variation in composition, richness and abundance of edaphic myriapod assemblages as a function of the distribution and structure of flooded and non-flooded habitats (spatial variation) and hydrological seasonality (temporal variation) in a floodplain of the northern Pantanal region of Mato Grosso, Brazil. Sampling was carried out in three areas of the Poconé Pantanal, along an altitudinal and inundation gradient consisting of inundated and non-inundated habitats and different vegetation formations. Three quadrats (10 x 10 m) were delimited within each habitat type, where sampling was performed using pitfall traps and mini-Winkler extractors during the dry, rising water, high water and receding water periods of two hydrological cycles within the Pantanal (2010/2011 and 2011/2012). A total of 549 millipedes were collected, consisting of 407 Diplopoda and 142 Chilopoda distributed in six orders, 12 families and 20 species. The assemblages composition varied throughout the seasonal periods, indicating that the rising water and dry periods differed from the high water and receding water periods. In addition to the variation between seasonal periods, myriapod richness and abundance also varied in relation to areas consisting of different vegetation formations. Thus, it can be concluded that the hydrological seasonality associated with the inundation gradient and different vegetation types were determinant in the heterogeneous spatial and temporal distribution of myriapod assemblages, validating that the conservation of these invertebrates in the Pantanal is directly linked to the preservation of vegetation, and consequently, ecosystem integrity.

In this paper we list the ant species collected in both remaining forests and urban areas in a South Amazonian landscape. The list includes 102 species, of which 29 are new records for the state of Rondônia, Brazil. This work demonstrates the gap in ant biodiversity surveys for Meridional Amazon as well as encouraging further research in this region.

The Brazilian Pantanal biome is one of the largest and most important floodplains in the world by virtue of its biodiversity and indispensable ecological services on local, regional, and global scales. Despite this importance, many gaps remain concerning its biodiversity as well as its generation and maintenance mechanisms. In view of expanding the information about its biological diversity, we compiled a list of Myriapoda (Arthropoda) species occurring in the Pantanal of Poconé, Mato Grosso, Brazil, based on the records from literature and on the specimens available in the zoological collections of Federal University of Mato Grosso -UFMT. A total of 33 Myriapoda species were recorded in the region. The Diplopoda species (20 spp.; 60.6%) are distributed 'between four orders: Polydesmida, represented by five families (Chelodesmidae, notably, with three species; Paradoxosomatidae and Pyrgodesmidae, with two species each; and Cyrtodesmidae and Fuhrmannodesmidae, with one species each, recently recorded in the region); Spirostreptida, represented by Spirostreptidae, with eight species; Spirobolida, with two species (one Rhinocricidae and one not identified); and Polyxenida. The Chilopoda (10 spp.; 30.3%) belong to three orders: Scolopendromorpha, with four species of the family Scolopendridae, two Scolopocryptopidae species, and one Cryptopidae species; Geophilomorpha, with the families Aphilodontidae and Schendylidae, with one species each; and Lithobiomorpha, with one Henicopidae species. Symphyla was represented by only two species (6.1%) of the family Scutigerellidae; and Pauropoda (3.0%) by a single species of Pauropodidae. The Myriapoda species richness, as well as the high number of new records in recent studies reinforce the importance of the northern region of the Pantanal biome as a diversity center with potential priority for measures aimed at the conservation of its many habitats.

Studies that address biodiversity and its supporting mechanisms in different ecosystems are fundamental to understanding the relationships between species and the prevailing environmental conditions within each habitat type. This study presents information on the phenology of Promestosomaboggianii (Silvestri, 1898) and its association with seasonal flood and dry events in a floodplain of Mato Grosso’s northern Pantanal region, Brazil. Sampling was carried out in three areas located between the Bento Gomes and Cuiabá rivers, on the Porto Cercado Road, Poconé-MT. Each sample area was composed of two treatments: (I) floodable habitats and (NI) non-floodable habitats. Three quadrats (10 x 10 m) were established within each treatment, with sampling carried out using pitfall traps and mini-Winkler extractors during the dry season, rising water, high water and receding water phases for the duration of two hydrological cycles within the Pantanal (2010/2011 and 2011/2012). A total of 295 P.boggianii individuals were sampled at different stages of development (except stages I and II), distributed between the rising water (209 ind., 70.8%), dry (76 ind., 25.8%) and receding water (10 ind., 3.4%) seasons. No specimens were sampled during the high water season. The higher abundances recorded between the dry and rising water seasons, primarily at early stages of development, indicate that P.boggianii is characterized as a univoltine species in these habitats. The data demonstrate that individuals of P.boggianii were more abundant in floodable habitats. In addition, the results show that the life cycle of this diplopod is sinchronized to the seasonal nature of this floodable environment, as a strategy to survive the extreme conditions of terrestrial and aquatic phases Brazil’s northern Pantanal region.

Estudo da heterogeneidade de variâncias na avaliação genética para o peso corporal aos 450 dias de idade em animais da raça NeloreAn study of the heterogeneity of variances on genetic evaluation for body weight at 450 days of age of Nelore breed cattle