Browsing by Autor "Perger, Robert"

Now showing 1 - 11 of 11

A true long horn-a new species of Macronemus Dejean, 1835 (Coleoptera, Cerambycidae, Lamiinae, Acanthoderini) from the Bolivian Andes.
(2018) Perger, Robert; Santos-Silva, Antonio
A new species of long-horned beetle, Macronemus waxrasapa sp. nov. from Bolivian Yungas forest, is described and illustrated.
A wolf in sheep's clothing: The description of a fly resembling jumping spider of the genus Scoturius Simon, 1901 (Araneae: Salticidae: Huriini).
(2018) Perger, Robert; Rubio, Gonzalo D
Fly resemblance in arthropods is much less common than e.g., resemblance to ants or wasps, and has been mainly observed in beetles. Putative fly mimicry in arachnids has been reported only from the jumping spider genus Saitis. However, recent literature has attributed the fly-resembling characteristics in Saitis to sexual signalling during courtship. The lack of observation of fly mimicry in spiders is not surprising as flies belong to the most important prey item group of spiders. In this study, a new fly-resembling species of the jumping spider tribe Huriini, Scoturius dipterioides sp. nov., from the pre-Andean Chiquitano forest at the Bolivian orocline is described and illustrated. The new species was tentatively placed into Scoturius because the epigynum has a single large elliptical opening. Scoturius dipterioides sp. nov. is distinguished from all other species of this tribe by a combination of following characteristics: epigynum with a large anterior elliptical atrium and initial portion of the copulation ducts dilated as a chamber (shared with Urupuyu); relatively joined copulation openings and short copulation ducts; kidney-shaped spermathecae, advanced at the atrium level. Several somatic features, two of them found exclusively in S. dipterioides sp. nov., increase the resemblance to flies. The Huriini are currently the only spider tribe that is suggested to feature fly mimics.
Contributions to the knowledge of Neotropical ant-like spiders: Myrmecotypus tahyinandu sp. n. from Bolivian Chiquitano forest, a new country record for M. niger, and indirect evidence for species-specific mimicry (Araneae: Corinnidae: Castianeirinae).
(2020) Perger, Robert; Rubio, Gonzalo D
Myrmecotypus tahyinandu sp. n. is described from the Bolivian Chiquitano forest, and M. niger Chickering, 1937 is recorded from Bolivia for the first time. The morphological differentiation among the closely related M. tahyinandu sp. n. and M. iguazu Rubio Arbino, 2009 is likely attributable to the selection for specific ant mimicry. Adults of M. tahyinandu sp. n. are accurate mimics of the ant Camponotus crassus Mayr, 1862, M. iguazu of C. sericeiventris (Guérin-Méneville, 1838), and M. niger of Dolichoderus bispinosus (Olivier, 1792). This study is the first to identify ant models for morphologically closely related Castianeirinae, providing a promising starting point for future research on ant mimicry.
Contributions to the knowledge of Neotropical Castianeirinae (Araneae: Corinnidae): redescription of Castianeira spinipalpis Mello-Leito, 1945, with first description of the male, and description of a new Myrmecotypus O. Pickard-Cambridge, 1894 from the Bolivian Moxos plains.
(2021) Pett, Brogan L; Perger, Robert
Two Neotropical species of the subfamily Castianeirinae are treated herein. Castianeira spinipalpis Mello-Leito, 1945 was described from a single female specimen; we provide a redescription of the female and the male is described for the first time. The species is newly recorded from Paraguay and Bolivia. Also, Myrmecotypus rubioi sp. nov. is described from the Bolivian Moxos plains, a tropical savanna ecoregion of the Beni department of northern Bolivia. The new species can be distinguished from others in the genus by having tibia I spination 3-2, coxa II whitish (the remainder dark), and a unique male palpal embolus with two broad embolic discs basal to the embolus tip.
Description of the male of Phoebe ornator (Tippmann, 1960) (Coleoptera: Cerambycidae: Lamiinae: Hemilophini), analysis of the species biogeography, and first observation of chromatic gender dimorphism in Hemilophini.
(2017) Perger, Robert; Santos-Silva, Antonio; Guerra, Fernando
The male of Phoebe ornator (Tippmann, 1960) is described. Chromatic gender dimorphism is also reported for the first time in the Hemilophini. In addition, new records are presented for P. ornator for the Brazilian states of Amazonas, Mato Grosso, Rondônia and São Paulo, and the Bolivian department of La Paz. The biogeography of P. ornator is analyzed.
Did the genus Parandrocephalus Heller, 1916 (Coleoptera, Cerambycidae, Callichromatini) cross the Wallace line? The taxonomic status of Parandrocephalus blairi Bentanachs & Vives 2009 and a new subgenus of Hexamitodera Heller, 1896, with notes on convergent evolution and secondary sexual characters.
(2013) Perger, Robert
The genera Parandrocephalus Heller, 1916 and Hexamitodera Heller, 1896 are reviewed and redescribed. Based on the combination of chromatic sexual dimorphism, velvety pubescence on the whole dorsal body and distinctly developed carina on the elytra, Parandrocephalus blairi Bentanachs & Vives, 2009 is transferred to Hexamitodera. A new subgenus, Sulcognatha Perger, is instituted to accommodate mandible, head and metasternal modifications in Hexamitodera blairi comb. n. that are lacking in the type species of Hexamitodera, Hexamitodera semivelutina. As indicated by fundamental structural differences in the mandibles of Parandrocephalus and Hexamitodera (Sulcognatha) blairi comb. n., the exaggerated secondary sexual traits and open procoxal cavities in both taxa are presumably the result of convergent evolution. Contrary to Bentanachs & Vives (2009), the presence of the two Parandrocephalus species in Sundaland and the endemism of Hexamitodera on Sulawesi agree well with the zoogeographical separation of both areas by the Wallace line.
First records of the jewel beetles Chrysobothrisdesmaresti (Laporte & Gory, 1836) and Hiperanthastempelmanni Berg, 1889 (Coleoptera: Buprestidae) in Bolivia.
(2015) Perger, Robert; Guerra, Fernando
The jewel beetle species Chrysobothrisdesmaresti (Laporte & Gory, 1836) and Hiperanthastempelmanni Berg, 1889, have been recorded in Bolivia for the first time. Both species were collected on xeric Acacia trees. As indicated by their presence on Acacia and previous records, both species may be endemic to the arid intermountain valleys of the Southern Bolivian and Northern Argentinean Andes as well as the Chaco lowland forests.
Grismadox elsneri sp. nov.a new species of ant-resembling sac spider from the Bolivian orocline, with indirect evidence of species-specific mimicry (Araneae: Corinnidae: Castianeirinae).
(2022) Perger, Robert; Rubio, Gonzalo D; Pett, Brogan L
A new species of ant-resembling sac spider of the subfamily Castianeirinae, Grismadox elsneri sp. nov., is described from the Sub-Andean area of the Bolivian orocline. The species was collected from savanna grass along the edges of the Chiquitano forest and is a putative mimic of the carpenter ants Camponotus cf. crassus or C. cf. blandus.
Myrmecotypus haddadi sp. nov.-a new species of ant resembling sac spider from the Bolivian orocline (Araneae: Corinnidae: Castianeirinae).
(2021) Perger, Robert; Rubio, Gonzalo D
A new species of ant resembling sac spider of the subfamily Castianeirinae, Myrmecotypus haddadi sp. nov. is described from the Sub-Andean area at the Bolivian orocline. The species was collected from low herbaceous vegetation along the edges of the Chiquitano and Cerradao forest.
The description of a new species of the Neotropical land crab genus Gecarcinus Leach, 1814 (Crustacea, Decapoda, Brachyura, Gecarcinidae).
(2014) Perger, Robert; Wall, Adam
In this contribution a new species of the land crab genus Gecarcinus Leach, 1814, from the Neotropical Pacific coast of South America is described and illustrated. In addition to its unique body color, Gecarcinus nobilii sp. n. is distinguished from congeners by a distinctly wider carapace front and differences in the shape of the infraorbital margin. The new species is not isolated from Gecarcinus populations from the Pacific coast of Central America by an insurmountable geographic barrier. Considering the closure of the Panamanian Isthmus as a calibration point for morphological divergence between the trans-isthmian mainland populations of Gecarcinus, the virtual lack of morphological differentiation (other than color) between them and the distinctness of G. nobilii sp. n. suggests that G. nobilii sp. n. evolved from a common ancestor before the Isthmus closed.
The land crab Johngarthiaplanata (Stimpson, 1860) (Crustacea, Brachyura, Gecarcinidae) colonizes human-dominated ecosystems in the continental mainland coast of Mexico.
(2014) Perger, Robert
The land crab Johngarthiaplanata (Stimpson, 1860) has been reported from the Baja California Peninsula and several oceanic islands in the Eastern Pacific as well as inshore islands of the Mexican, Costa Rican and Colombian coast. However, the species has not been observed on the continental mainland, as it is likely that the high diversity of terrestrial predators/competitors make the establishment of mainland populations nearly impossible. In this contribution, several new records of this species that have been observed in urban areas along the continental Pacific coast of Mexico are reported. These records demonstrate that the presence of humans does not necessarily have a negative impact on land crab species. Indeed, the presence of humans may actually discourage the presence of native crab predators/competitors and hence increase the likelihood of a successful mainland settlement of land crab species that are otherwise island and peninsula restricted. The presence of Johngarthiaplanata is ecologically relevant for coastal forests because gecarcinid crabs significantly influence plant recruitment and Johngarthiaplanata is considerably larger than the mainland species Gecarcinusquadratus.