A new species of Tricorythopsis Traver, 1958 (Ephemeroptera: Leptohyphidae) from Par state, Brazil.

A new species of Tricorythopsis is described, illustrated and diagnosed based on nymphs from Par state, Brazil. Tricorythopsis similis sp. nov. is related to Tricorythopsis rondoniensis (Dias, Cruz Ferreira) based on abdominal terga IIIVII with acute tubercles medially located on posterior margins, and by the absence of the transversal line on operculate gill. However, the new species can be identified by the following combination of characteristics: general coloration yellowish brown, with blackish and purplish marks irregularly distributed; maxillary palp 1-segmented; segment II of labial palp shorter than segment I and longer than segment III; femora and tibiae with margins covered by long, pectinate setae; tarsal claws with 4 to 5 marginal denticles and 4+2 very small, submarginal denticles. This is the first species of Tricorythopsis recorded from Par state.

Thraulodes Ulmer 1920 (Ephemeroptera: Leptophlebiidae) from Esprito Santo state, Brazil.

Based on material collected during the past 10 years in the State of Esprito Santo and adjacent areas in Minas Gerais, Southeastern Brazil, we identified three species of the genus Thraulodes: T. itatiajanus Traver Edmunds, for which we present new records and description of the female imago; T. luisae Souto, Da-Silva Nessimian, first recorded for the state and for which we describe the nymphal stage; and T. alegre sp. nov., described based on male and female imago. The main diagnostic characteristics of the new species are: color of abdominal terga IVI whitish translucent, terga IIVI with subrectangular dark brown mark near posterior margin and with midway spot; styliger plate triangular and whitish; penes light yellow, with lateral pouch and penes spines long and tapered, with robust bases.

Redescription of adults of Simulium jeteri (Py-Daniel, Darwich, Mardini, Strieder amp; Coscarón, 2005) (Diptera: Simuliidae).

Simulium jeteri (Py-Daniel, Darwich, Mardini, Strieder Coscarón, 2005) was not fully described, because only pharate male and female adults extracted from pupae were used for the original descriptions. Important diagnostic characters were either incompletely or poorly described. During field work in areas at the same hydrographic basin of the type-locality, we were able to rear adult stages. The main objective of this study is to redescribe the male and female of S. jeteri, providing a complete description, including morphological characteristics not reported before, such as, presence of a median ventral projection on male ventral plate and a bilobed anal lobe on female terminalia. Additional characters of pupae and larvae are given. The addition of new characters will be useful to better understand phylogenetic relationships among species in this group. Females of S. jeteri are not known to bite.