PIV Measurements of the Wake Formation from a Rough Flat Plate

Wake flows are prevalent in a wide range of engineering applications and their behaviour can significantly impact engineering design and performance. A considerable body of work exists on smooth body wake structures and flows over rough bodies, however, there is a lack of fundamental physical understanding of the amalgamation of the two fields. Two-component two-dimension particle image velocimetry (2C-2D PIV) is used to investigate the effect of surface roughness on the formation of large scale structures in the near wake of a thin flat plate. Both high-speed and low-speed, high-resolution PIV setups have been used to investigate the effect of surface roughness on the boundary layer and the near wake of the plate to gain insight into the underlying physical connection between these regions.

Chaimowiczia: a new Iuiuniscinae genus from Brazil (Oniscidea, Synocheta, Styloniscidae) with the description of two new troglobitic species

A new genus of Styloniscidae, Chaimowicziagen. nov., is described with two new species: Chaimowiczia tatussp. nov. from Gruta do Padre cave (Santana, Bahia) and Chaimowiczia uaisp. nov. from Lapa d’água do Zezé cave (Itacarambi, Minas Gerais). The new genus and species were allocated into the subfamily Iuiuniscinae, hitherto monotypic, by the pronounced rectangular-shaped lateral pereonites epimera, dorsal surface smooth, body outline continuous without a gap between pereon and pleon, and pleonites 3 to 5 developed forming tips. The two species of Chaimowiczia gen. nov. differ in the shape of cephalon antennal lobes, pereonite 1 epimera, pleonite 5 posterior margin and uropod exopod and endopod proportion.

Three new species of Hyalella (Crustacea: Amphipoda: Hyalellidae) from the Southern Brazilian Coastal Plain

In this study, three new species of Hyalella (Crustacea: Amphipoda: Hyalellidae) are described based on specimens collected in wetlands located in three freshwater ecoregions (Southeastern Mata Atlântica, Tramandaí-Mampituba and Laguna dos Patos) of the southern Brazilian Coastal Plain (states of Rio Grande do Sul and Santa Catarina). Hyalella minuana n. sp. was recorded in the southernmost region of the state of Rio Grande do Sul. This species is characterized by presenting smooth body surface, epimeral plates not acuminated, nine serrate setae on the inner face of gnathopod 1, and peduncle of uropod 3 with four cuspidate setae with accessory seta and without plumose seta on the margin of the telson. Hyalella lagoana n. sp. was recorded in the northern region of Rio Grande do Sul and southern region of Santa Catarina. This species shows body surface smooth, epimeral plates not acuminated, nine serrate setae on the inner face of gnathopod 1, peduncle of uropod 3 with five cuspidate setae with accessory seta, and telson with six cuspidate setae with accessory seta without plumose seta on the margins. Hyalella sambaqui n. sp. was recorded in the state of Santa Catarina. This species is characterized by presenting smooth body surface, epimeral plates not acuminated, six serrate setae on the inner face of gnathopod 1, peduncle of uropod 3 with three cuspidate setae with accessory seta, and telson with three cuspidate setae with accessory seta and four plumose setae on the margin of the telson. The new records elevates the known diversity of species of Hyalella in the Brazilian territory to 33 species (19 in the southern Brazilian region) and to 83 species in the Americas.

Description of male and habitat of Haroldius turnai Král (Coleoptera: Scarabaeidae: Scarabaeinae)

The small-sized genus Haroldius Boucomont, 1914 consists of 38 known species widely distributed in the Old World including South Asia, Southeast Asia and West Africa (Pereira 1954; Krikken & Huijbregts 2006; Král & Hájek 2012). Members of this genus are probably saprophagous or mycophagous (Scheuern 1995) and so far were collected by light traps, sifted from leaf litter or soil and captured by flight interception traps (Paulian 1939; Paulian & Scheuern 1994; Krikken & Huijbregts 2006). Some researches suggested that they could have precise ecological relationship with ants. Their myrmecophily habit was indicated mainly by the special morphological characters including smooth body and the characteristically broad­ened and flattened tibiae (Pereira 1954; Krell & Philips 2010). However, their bi­ology are still rarely reported, and the larvae are still unknown (Pereira 1954; Krikken & Huijbregts 2006).