Two new species of Abernessia Arlé (Pompilidae,?Ctenocerinae)

Two new species are added to the rare pompilid genus Abernessia Arlé. Abernessia capixaba sp. n. and A. giga sp. n. are described and illustrated. This is the first record of the genus from the states of Espírito Santo and Minas Gerais, Brazil. The genus now contains four species. A brief discussion of generic characters, illustrations, and a key to the known species of Abernessia are provided.     

Two new species and a new subgenus of toothed Brachyhypopomus electric knifefishes (Gymnotiformes,Hypopomidae) from the central Amazon and considerations pertaining to the evolution of a monophasic electric organ discharge

We describe two new, closely related species of toothed Brachyhypopomus (Hypopomidae: Gymnotiformes: Teleostei) from the central Amazon basin and create a new subgenus for them. Odontohypopomus, new subgenus of Brachyhypopomus, is diagnosed by (1) small teeth present on premaxillae; (2) medialmost two branchiostegal rays thin with blades oriented more vertically than remaining three rays; (3) background color in life (and to lesser extent in preservation) distinctly yellowish with head and sides peppered with small, widely spaced, very dark brown stellate chromatophores that greatly contrast with light background coloration; (4) a dark blotch or bar of subcutaneous pigment below the eye; (5) electric organ discharge waveform of very long duration (head-positive phase approx. 2 milliseconds or longer, head-negative phase shorter or absent) and slow pulse repetition rate (3–16 Hz). The type species of the new subgenus, Brachyhypopomus (Odontohypopomus) walteri sp. n., is diagnosed by the following additional character states: (1) subcutaneous dark pigment at base of orbit particularly prominent, (2) body semi-translucent and nearly bright yellow background coloration in life, (3) a biphasic electric organ discharge (EOD) waveform of very long duration (between 3.5 and 4 milliseconds at 25° C) with head-positive first phase significantly longer than second head-negative phase in both sexes. Brachyhypopomus (Odontohypopomus) bennetti sp. n. is diagnosed by two character states in addition to those used to diagnose the subgenus Odontohypopomus: (1) a deep electric organ, visible as large semi-transparent area, occupying approximately 14–17% body depth directly posterior to the abdominal cavity in combination with a short, but deep, caudal filament, and (2) a monophasic, head-positive EOD waveform, approximately 2.1 milliseconds in duration in both sexes. These are the only described rhamphichthyoid gymnotiforms with oral teeth, and Brachyhypopomus bennetti is the first Brachyhypopomus reported to have a monophasic (head-positive) EOD waveform. Unlike biphasic species, the waveform of its EOD is largely unaffected by tail damage from predators. Such injuries are common among specimens in our collections. This species’ preference for floating meadow habitat along the major channels of the Amazon River basin may put it at particularly high risk of predation and “tail grazing.”     

Neophylax kolodskii (Trichoptera: Uenoidae), A New Species from the Great Smoky Mountains National Park,U.S.A.

Neophylax kolodskii sp. n. from Great Smoky Mountains National Park is described and illustrated from adult specimens.     

A revision of Megalocraerus Lewis, 1902 (Coleoptera,Histeridae: Exosternini)

The formely monotypic Neotropical genus Megalocraerus Lewis is revised to include five species, known from southeastern Brazil to Costa Rica: Megalocraerus rubricatus Lewis, Megalocraerus mandibularis sp. n., Megalocraerus chico sp. n., Megalocraerus madrededios sp. n., and Megalocraerus tiputini sp. n. We describe the species, map their distributions, and provide a key for their identification. Their subcylindrical body form and emarginate mesosternum have previously hindered placement to tribe, although their curent assignment to Exosternini now appears well supported by morphological evidence. Nothing is known of the natural history of the species.     

A new species of Dicrotendipes (Diptera: Chironomidae) from Costa Rica

The adult male of Dicrotendipes baru is described from the Dominical area of southwestern Costa Rica. The species is characterized by its elongate club-like superior volsella. This species represents the third member of the genus known from Costa Rica.     

A new genus and species of Coenosiini from Costa Rica (Diptera,Muscidae, Coenosiinae)

Palpilongus gen. n. is herein described for one species – Palpilongus bifurcus sp. n., from Costa Rica, based on male and females. The striking morphological characters of the species – palpus very long, about as long as prementum; upper calypter truncate and very short and setae of male sternite 5 bifurcated, confirm that this new species is also a new genus in the tribe Coenosiini. Male and female terminalia were dissected and illustrated.