Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Roberto Hiroaki Nagahama is active.

Publication


Featured researches published by Roberto Hiroaki Nagahama.


Journal of Arachnology | 2010

Loxosceles chapadensis (Araneae: Sicariidae): a new recluse spider species of the gaucho group from Brazil

Rogério Bertani; Caroline Sayuri Fukushima; Roberto Hiroaki Nagahama

Abstract A new species of the medically important recluse spider genus Loxosceles Heinecken & Lowe 1832 is described from the State of Bahia, Brazil. The species occurs between rocks and crevices, as well as in and around man-made structures. The new species belongs to the gaucho group, as evidenced by the spermathecal shape and color pattern. The presence of a long male palpal tibia is unusual in the gaucho group; thus, the inclusion of the new species in this group is discussed.


ZooKeys | 2012

Loxosceles niedeguidonae (Araneae, Sicariidae) a new species of brown spider from Brazilian semi-arid region

Rute M. Gonçalves-de-Andrade; Rogério Bertani; Roberto Hiroaki Nagahama; Maria Fatima Ribeiro Barbosa

Abstract A new species of recluse spider, Loxosceles niedeguidonae sp. n., is described from the Parque Nacional Serra da Capivara, State of Piauí, Brazil. This is the first endemic species described from Brazilian semi-arid environment. The species is included in gaucho group of Gertsch (1967) due to its spermathecal shape and is considered close to Loxosceles chapadensis Bertani, Fukushima & Nagahama, 2010 by the unusual long male palpal tibia, a character not common for species of this group. An updated key for Loxosceles species of gaucho group is presented.


Journal of Arachnology | 2008

The identity of Mygale brunnipes C.L. Koch 1842 (Araneae, Theraphosidae), with a redescription of the species and the description of a new genus

Caroline Sayuri Fukushima; Roberto Hiroaki Nagahama; Rogério Bertani

Abstract We describe Kochiana new genus to accommodate a small Brazilian theraphosine species described originally as Mygale brunnipes by Koch (1842), resulting in Kochiana brunnipes new combination. Recently, specimens were rediscovered in northeastern Brazilian Atlantic rainforest. A preliminary cladistic analysis using equal weights parsimony and implied weights, was carried out to examine its phylogenetic placement. Kochiana new genus was monophyletic in all trees regardless of weighting scheme or concavity used. There is preliminary evidence for Kochiana new genus monophyly and weak evidence for its placement as sister group of Plesiopelma. Kochiana new genus can be characterized by the presence of a hornshaped spermatheca in females and males with a palpal bulb having prolateral accessory keels and a well developed medial crest on the embolus apex.


Zoologia (Curitiba) | 2012

Metriura Drolshagen & Bäckstam, 2009 (Araneae: Dipluridae) is a junior synonym of Fufius Simon, 1888 (Araneae: Cyrtaucheniidae)

Rogério Bertani; Caroline Sayuri Fukushima; Roberto Hiroaki Nagahama

The monotypic diplurid Metriura Drolshagen & Backstam, 2009 is placed in synonymy with Fufius (Cyrtaucheniidae) syn. nov. since Metriura lacks two of three diplurid synapomorphies (elongate posterior lateral spinnerets and the widely separated posterior median spinnerets) and shares synapomorphies with both aporoptychine cyrtaucheniids (subquadrate maxilla and a longer than wider labium) and Fufius (recurved and broad fovea, the typical incrassate tibia I of the male, with the spur having a single short branch and an apical megaspine, the basally curved metatarsus I and provided with a ventral tubercle). The type species of Metriura, M. striatipes Drolshagen & Backstam, 2009 is considered valid, and due to the synonymy of Metriura with Fufius, Fufius striatipes (Drolshagen & Backstam, 2009) comb. nov. is established.


ZooKeys | 2013

Three new species of Fufius Simon, 1888 (Araneae, Cyrtaucheniidae) from Brazil with the redescription of Fufius funebris Vellard, 1924 and description of the female of Fufius lucasae Guadanucci & Indicatti, 2004

Diego Ribeiro Migueis Ortega; Roberto Hiroaki Nagahama; Paulo César Motta; Rogério Bertani

Abstract The mygalomorph neotropical genus Fufius Simon, 1888 comprises ten species, distributed from Guatemala in Central America to southeastern Brazil, in South America. Most of the species were described from northern South America, in the Amazonian region. Only F. funebris Vellard, 1924 and F. lucasae Guadanucci & Indicatti, 2004 are known from regions more to the south of the continent. Herein we describe three new Brazilian species, Fufius minusculus sp. n. and F. jalapensis sp. n. from the state of Tocantins, and F. candango sp. n. from Distrito Federal. The female of F. lucasae is described for first time and the male and female of F. funebris are redescribed based on specimens collected at the type locality.


Zoologia | 2009

Nhandu tripepii is a senior synonym of Nhandu vulpinus (Araneae: Theraphosidae)

Roberto Hiroaki Nagahama; Caroline Sayuri Fukushima; Rogério Bertani

The holotype of Eurypelma tripepii Dresco, 1984 from state of Para, Brazil, is revised and illustrated. Its palpal bulb and tibial apophysis are similar in shape to species of Nhandu Lucas, 1983. Therefore, the species is transferred to the genus Nhandu, establishing the new combination Nhandu tripepii (Dresco, 1984) comb. nov., which is considered a senior synonym of Nhandu vulpinus (Schmidt, 1998) syn. nov. The protuberances present on the holotypes chelicerae are here considered a morphological anomaly.


PLOS Neglected Tropical Diseases | 2013

Venom of the brazilian spider sicarius ornatus (Araneae, sicariidae) contains active sphingomyelinase d: Potential for toxicity after envenomation

Priscila Hess Lopes; Rogério Bertani; Rute M. Gonçalves-de-Andrade; Roberto Hiroaki Nagahama; Carmen W. van den Berg; Denise V. Tambourgi


Zootaxa | 2011

Revalidation of Pterinopelma Pocock 1901 with description of a new species and the female of Pterinopelma vitiosum (Keyserling 1891) (Araneae: Theraphosidae: Theraphosinae)

Rogério Bertani; Roberto Hiroaki Nagahama; Caroline Sayuri Fukushima


Zoologia (Curitiba) | 2012

Vitalius nondescriptus comb. nov. (Araneae: Theraphosidae: Theraphosinae): an example of theraphosid taxonomic chaos

Rogério Bertani; Roberto Hiroaki Nagahama; Caroline Sayuri Fukushima


Archive | 2009

SHORT COMMUNICATION Nhandu tripepii is a senior synonym of Nhandu vulpinus (Araneae: Theraphosidae)

Roberto Hiroaki Nagahama; Caroline Sayuri Fukushima; Rogério Bertani

Collaboration


Dive into the Roberto Hiroaki Nagahama's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge