RESUMO

Three new species of recluse spiders are described from Brazilian caves with both males and females. Loxosceles boqueirao Bertani & Gallão sp. nov. is found in the State of Bahia, in the Serra do Ramalho karst area, it belongs to the rufescens species group, and is closely related to L. cardosoi Bertani, von Schimonsky & Gallão, 2018 and L. carinhanha Bertani, von Schimonsky & Gallão, 2018 from the same karst area. Thus, there are now three species in the Serra do Ramalho karst area closely related, but noticeably distinct morphologically from other species of Loxosceles. Loxosceles planetaria Bertani & Gallão sp. nov. and L. bodoquena Bertani & Gallão sp. nov. are found in the State of Mato Grosso do Sul, in the Serra da Bodoquena karst area. They belong to the gaucho species group and are closely related to L. gaucho Gertsch, 1967. These are the first species of Loxosceles described from this karst area in the State of Mato Grosso do Sul. Loxosceles boqueirao sp. nov. and L. bodoquena sp. nov. bear some troglomorphisms and are, herein, proposed as troglobitic species, whereas L. planetaria sp. nov. is proposed as a troglophilic species. Brazil has now 22 described species of Loxosceles.

RESUMO

The first two anophthalmic species of spiders of the genus Ochyrocera Simon, 1892, are described for caves located in the iron formation of Floresta Nacional (FLONA) de Carajás in southeastern Pará State, Brazil. The caves are located in the municipalities of Parauapebas and Canaã dos Carajás, in the eastern portion of the Amazon Forest domain. Ochyrocera ritxoco sp. nov. and O. ritxoo sp. nov. are described based on males and females. The species have similar body characteristics with the total absence of eyes and complete depigmentation, characteristics that indicate possible evolution in subterranean environments , and thus are classified as troglobites. Each species is associated with a single geomorphological unit (mountain range), with Ochyrocera ritxoco sp. nov. being restricted to caves of Serra Norte (North Mountain) and O. ritxoo sp. nov. to caves of Serra Sul (South Mountain). Both species were collected in aphotic zones of the caves. Small and tangled webs of O. ritxoco sp. nov. were observed under blocks of stone in the soil or in cracks of the walls.

RESUMO

Animals evolve their sensory systems and foraging behaviours to adapt and colonize new and challenging habitats such as the dark cave environment. Vibration attraction behaviour (VAB) gives fish the ability to locate the source of a water disturbance in the darkness. VAB evolved in the blind Mexican cave tetra, Astyanax mexicanus. VAB is triggered in cavefish by vibration stimuli peaking at 35 Hz, which is within the main spectrum of water fluctuations produced by many prey crustaceans and insects. VAB has a genetic component and is correlated to an increased number of head mechanosensory neuromasts in the eye orbital region when compared to surface fish. Previous competitive prey capture assays have supported the advantage of VAB for foraging in the dark. Despite its putative adaptive function, VAB has been described as absent in some Astyanax cave populations (Tinaja and Molino) but present in others (Pachón, Piedras, Toro and Sabinos). Here we have tested the occurrence of VAB in the field and in multiple cave populations using a vibrating device in natural pools. Our results confirmed the presence of VAB in caves such as Pachón, Toro and Sabinos but showed that VAB is also present in the Tinaja and Molino cave populations, previously reported as VAB-negative in laboratory experiments. Thus, VAB is available throughout the range of hypogean A. mexicanus. However, and most notably, within a given cave the levels of VAB were highly variable among different pools. Fish at one pool may express no VAB, while fish at another nearby pool of the same cave may actively show VAB. While a variety of environmental conditions may foster this diversity, we found that individuals inhabiting pools with a high abundance of organic matter have reduced expression of VAB. In contrast, in pools with little organic debris where fish probably depend more on hunting than on scavenging, VAB is enhanced. Our results suggest that expression of VAB is a plastic trait whose variability can depend on local conditions. Such plasticity may be required within and among caves where high environmental variability between pools results in a diverse availability of food.

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RESUMO

Four new species of the spider genus Ochyrocera Fage, 1912 are described from iron caves in the state of Minas Gerais, Brazil. Here we present the third anophtalmic and depigmented species of the genus, O. dorinha sp. nov., and three other depigmented species: O. monica sp. nov., O. magali sp. nov. and O. rosinha sp. nov. Only O. dorinha sp. nov. and O. rosinha sp. nov. are considered as troglobites due the ocular reduction or anophthalmia and elongated appendages, two troglomorphic features absent in the other species described.

RESUMO

The first two anophthalmic species of spiders of the genus Ochyrocera Simon, 1892, are described for caves located in the iron formation of Floresta Nacional (FLONA) de Carajás in southeastern Pará State, Brazil. The caves are located in the municipalities of Parauapebas and Canaã dos Carajás, in the eastern portion of the Amazon Forest domain. Ochyrocera ritxoco sp. nov. and O. ritxoo sp. nov. are described based on males and females. The species have similar body characteristics with the total absence of eyes and complete depigmentation, characteristics that indicate possible evolution in subterranean environments , and thus are classified as troglobites. Each species is associated with a single geomorphological unit (mountain range), with Ochyrocera ritxoco sp. nov. being restricted to caves of Serra Norte (North Mountain) and O. ritxoo sp. nov. to caves of Serra Sul (South Mountain). Both species were collected in aphotic zones of the caves. Small and tangled webs of O. ritxoco sp. nov. were observed under blocks of stone in the soil or in cracks of the walls.

RESUMO

In this paper, we describe Coarazuphium lundi sp. nov., from a single male specimen collected in Gruta 06L cave located in the municipality of Prudente de Morais (Minas Gerais state, Brazil). The two most striking differences between C. lundi and other species of the genus is the presence of two pairs of posterior supraorbital setae and the elytra shape with parallel, not rounded sides. Coarazuphium pains Álvares Ferreira 2002 is an endemic species restricted to a few caves at the Bambuí Carbonatic Group in the midwest of Minas Gerais state, Brazil. The holotype of C. pains was unfortunately lost in 2010, due to a fire that destroyed almost the entire zoological collection at the Butantã Institute, São Paulo state in Brazil. In recent years, several species of the genus have been described and compared to C. pains only based on its paper description, clearly prompting the need for the C. pains neotype designation. In order to provide a necessary standard for comparison, a neotype is designed for this species based on the material collected from the best approximation of the type locality (caves). Lastly, we also provide a brief discussion on the presence of eyespots of C. cessaima, originally described as blind.

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We report the complete mitochondrial genome sequence of Glomeridesmus spelaeus, the first sequenced genome of the order Gomeridesmida. The genome is 14,825 pb in length and encodes 37 mitochondrial (13 PCGs, 2 rRNA genes, 22 tRNA) genes and contains a typical AT-rich region. The base composition of the mitogenome was A (40.1%), T (36.4%), C (15.8%), and G (7.6%), with an GC content of 23.5%. Our results indicated that G. spelaeus is only distantly related to the other Diplopoda species with available mitochondrial genomes in the public databases. As the broadest genetic characterization of a Glomeridesmida species available to date, the mitogenome of G. spelaeus will help understanding the evolution of such a little-known millipede group. Also, our data will be important for the characterization and conservation of the diverse invertebrate troglofauna of the Amazonian caves.

RESUMO

Seven new species of the spider genus Matta are described from caves in the State of Minas Gerais, Brazil: M. zuiuda sp. n., Matta pititinha sp. n., Matta humhum sp. n., Matta cambito sp. n., Matta humrrum sp. n., Matta nuusga sp. n., and Matta teteia sp. n. Among these seven species, six have morphological features consistent with specialization to the subterranean environment and we hypothesize that they are troglobites. One species, Matta zuiuda sp. n., shares morphology similar to M. hambletoni Crosby and M. angelomachadoi Brescovit which are known from surface populations in the State of Minas Gerais.

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RESUMO

The family Microstigmatidae is composed of two subfamilies, Microstigmatinae and Micromygalinae, seven genera and 16 species. Micromygalinae is monotypic, comprising the species Micromygalediblemma Platnick & Forster, 1982 from Panama. A new genus, Tonton is described as a new member of the Micromygalinae. Masteriaemboaba Pedroso, Baptista & Bertani, 2015, is transferred to the new genus and six new species from Brazil are described and attributed to Tonton gen. n.: the type species, T.itabirito sp. n., T.queca sp. n., T.matodentro sp. n. and T.sapalo sp. n., all from the state of Minas Gerais; T.ipiau sp. n. from the state of Bahia and T.quiteria sp. n. from the state of Maranhão. Among the cavernicolous species, only T.itabirito sp. n. is considered troglobitic by the total absence of eyes.

RESUMO

Seven new species of the spider genus Matta are described from caves in the State of Minas Gerais, Brazil: M. zuiuda sp. n., Matta pititinha sp. n., Matta humhum sp. n., Matta cambito sp. n., Matta humrrum sp. n., Matta nuusga sp. n., and Matta teteia sp. n. Among these seven species, six have morphological features consistent with specialization to the subterranean environment and we hypothesize that they are troglobites. One species, Matta zuiuda sp. n., shares morphology similar to M. hambletoni Crosby and M. angelomachadoi Brescovit which are known from surface populations in the State of Minas Gerais.

RESUMO

The family Microstigmatidae is composed of two subfamilies, Microstigmatinae and Micromygalinae, seven genera and 16 species. Micromygalinae is monotypic, comprising the species Micromygale diblemma Platnick & Forster, 1982 from Panama. A new genus, Tonton is described as a new member of the Micromygalinae. Masteria emboaba Pedroso, Baptista & Bertani, 2015, is transferred to the new genus and six new species from Brazil are described and attributed to Tonton gen. n.: the type species, T. itabirito sp. n., T. queca sp. n., T. matodentro sp. n. and T. sapalo sp. n., all from the state of Minas Gerais; T. ipiau sp. n. from the state of Bahia and T. quiteria sp. n. from the state of Maranhao. Among the cavernicolous species, only T. itabirito sp. n. is considered troglobitic by the total absence of eyes.

RESUMO

The new species Cylindroniscus platoi n. sp. is herein described. As far as known, the species occurs only in three caves developed in a continuous limestone outcrop at Pedro Leopoldo municipality, Minas Gerais State. Cylindroniscus platoi n. sp. is regarded as an endemic troglobite based on its limited distribution and on non-obvious troglomorphisms found on its body surface.

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Cave-adapted organisms are often characterized by a reduction in pigmentation, eyesight, and enhanced mechanosensory functions. Previous studies have described the genetic basis for a depigmented phenotype in multiple independent populations of the Blind Mexican Tetra, Astyanax mexicanus; the reduction in melanin content (brown; Mc1r). At least seven wild populations express the brown phenotype. In three populations, there are two different coding sequence alterations affecting Mc1r and the remaining four populations show the accumulation of sequence mutations affecting the 5' regulatory region. Thus, the Mc1r gene has been the repeated and independent location of mutations in Astyanax. As such, it would appear that this gene is a target during regressive evolution of cave adapted organisms. If this is the case, it would be expected that other cave adapted fish would have mutations in the same gene. We study here the stygobitic catfish Astroblepus pholeter, a depigmented fish found within some river caves in Ecuador. A. pholeter displays mutations in ultra-conserved areas of the pigment-controlling gene, Mc1r, that have been linked to pigment regulation in other organisms. It is thus concluded that Mc1r, a gene known to control pigment variation in many organisms, may be the target of cavernicole regressive evolution across species in different families of fish.

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Two new species of freshwater crabs of the pseudothelphusid genus Neostrengeria Pretzmann, 1965, N. fernandezi n. sp., and N. lassoi n. sp., are described. The genus is endemic to the eastern Andes of Colombia. Neostrengeria fernandezi was collected in Las Cacas cave, Pauna, Boyacá Department and N. lassoi in a stream within Los Aviones cave, La Guadalupe, Santander Department, within the cave as well as in a waterfall outside the cave. With the addition of N. fernandezi and N. lassoi the total number of species of the genus Neostrengeria increases to 27. Like all others species of Neostrengeria, the new species are distinguished primarily by the morphology of the first male gonopod, particularly by the form of lateral, accessory and mesial lobes, outline of the apex, and the mesio-caudal projection of the spermatic channel.

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The laterosensory system is a mechanosensory modality involved in many aspects of fish biology and behavior. Laterosensory perception may be crucial for individual survival, especially in habitats where other sensory modalities are generally useless, such as the permanently aphotic subterranean environment. In the present study, we describe the laterosensory canal system of epigean and subterranean species of the genus Ituglanis (Siluriformes: Trichomycteridae). With seven independent colonizations of the subterranean environment in a limited geographical range coupled with a high diversity of epigean forms, the genus is an excellent model for the study of morphological specialization to hypogean life. The comparison between epigean and subterranean species reveals a trend toward reduction of the laterosensory canal system in the subterranean species, coupled with higher intraspecific variability and asymmetry. This trend is mirrored in other subterranean fishes and in species living in different confined spaces, like the interstitial environment. Therefore, we propose that the reduction of the laterosensory canal system should be regarded as a troglomorphic (= cave-related) character for subterranean fishes. We also comment about the patterns of the laterosensory canal system in trichomycterids and use the diversity of this system among species of Ituglanis to infer phylogenetic relationships within the genus. J. Morphol. 278:4-28, 2017. ©© 2016 Wiley Periodicals,Inc.

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Coecobrya anaguilae sp. nov., a new species of springtail from Cango Caves, South Africa is described and illustrated. The new species is similar to other species of tenebricosa-group such as C. communis (Chen & Christiansen), C. edenticulata (Handschin), and C. tropicalis Qu, Chen & Greenslade in some elements of dorsal chaetotaxy, absence of eyes, unguis with one unpaired median tooth, and manubrium without smooth chaetae, but differs from them in dorsal head, mesothoracic and collophore chaetotaxy. This is the first species of Coecobrya described from Africa as well as the first indisputable record of the genus for the whole continent. In this study an updated key to the species of the genus is provided, adding 14 species to the most recently published identification key. We also discuss some aspects of distribution and evolution of Coecobrya.

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RESUMO

A new subterranean and troglomorphic species of Ituglanis Costa and Bockmann, 1993 is described from the carbonatic karst area of northeastern Goiás state, upper Tocantins River Basin, central Brazil, representing the sixth subterranean species of the genus described from the same region. Ituglanis boticario sp. nov. is diagnosed by a combination of unusual characters for the genus: body pigmentation forming longitudinal stripes, 7-8 pairs of ribs, presence of the anterior segment of the infraorbital laterosensory canal, and usually 8 pectoral-fin rays. Due to the absence of epigean populations and the presence of some degree of morphological specialization to the subterranean environment, it can be classified as a troglobite (i.e., exclusively subterranean). The description of this species increases the importance of the northeastern Goiás region as a biodiversity spot for subterranean ichthyofauna, mainly Ituglanis. The region demands urgent political efforts to ensure the preservation of its speleobiological patrimony, including the Tarimba cave system, one of the largest caves in Brazil and type-locality of I. boticario sp. nov.

Assuntos

RESUMO

A new subterranean and troglomorphic species of Ituglanis Costa and Bockmann, 1993 is described from the carbonatic karst area of northeastern Goiás state, upper Tocantins River Basin, central Brazil, representing the sixth subterranean species of the genus described from the same region. Ituglanis boticario sp. nov. is diagnosed by a combination of unusual characters for the genus: body pigmentation forming longitudinal stripes, 7-8 pairs of ribs, presence of the anterior segment of the infraorbital laterosensory canal, and usually 8 pectoral-fin rays. Due to the absence of epigean populations and the presence of some degree of morphological specialization to the subterranean environment, it can be classified as a troglobite (i.e., exclusively subterranean). The description of this species increases the importance of the northeastern Goiás region as a biodiversity spot for subterranean ichthyofauna, mainly Ituglanis. The region demands urgent political efforts to ensure the preservation of its speleobiological patrimony, including the Tarimba cave system, one of the largest caves in Brazil and type-locality of I. boticario sp. nov.(AU)

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RESUMO

Trichomycterus dali, new species, is described from flooded limestone caves in Serra da Bodoquena karst area, State of Mato Grosso do Sul, Central Brazil. The new species is diagnosed by a unique character in the genus, the presence of conspicuous, ridge-like adipose folds lining dorsally throughout the body. Trichomycterus dali can be further distinguished readily from epigean congeners by the reduction of eyes and skin pigmentation (except for T. gorgona), and from remaining congeners (i.e., all hypogean plus T. gorgona) by the total loss of eyes, not visible externally (except for T. sandovali and T. spelaeus). Other diagnostic features includes very long barbels, especially the nasal (99.3-143.5 percent HL) and the maxillary (97.0-131.3 percent HL), pectoral-fin ray count reaching I,9 and a unique cranial fontanel with a conspicuous constriction on the meeting point of supraoccipital and the two frontal bones. The troglobitic status of the species is suggested by the presence of troglomorphisms on an advanced degree, especially the reduction of skin pigmentation, the total loss of eyes and the enlarged barbels. In addition, the presence of a well developed adipose fold in adults may indicate a distinctive adaptation acquired by neoteny to withstand the food scarce conditions of its hypogean habitat.

Trichomycterus dali, espécie nova, é descrita de cavernas calcárias alagadas na área cárstica da Serra da Bodoquena, estado do Mato Grosso do Sul, Brasil central. A nova espécie é diagnosticada por um caráter único no gênero, a presença de dobras adiposas conspícuas, em forma de crista, passando por toda a região dorsal do corpo. Trichomycterus dali pode ser ainda diferenciada facilmente de suas congêneres epígeas pela redução dos olhos e da pigmentação cutânea (exceto para T. gorgona), e das congêneres restantes (isto é, todas as hipógeas mais T. gorgona) pela perda total dos olhos, não visíveis externamente (exceto para T. sandovali e T. spelaeus). Outras características diagnósticas incluem barbilhões muito longos, especialmente o nasal (99,3-143,5 por cento do comprimento da cabeça) e o maxilar (97,0-131,3 por cento do comprimento da cabeça), contagem de raios da nadadeira peitoral atingindo I,9 e uma fontanela cranial única com uma constrição conspícua no ponto de encontro do supraoccipital e dos dois ossos frontais. O status troglóbio da espécie é sugerido pela presença de troglomorfismos em avançado grau, especialmente a redução da pigmentação cutânea, a perda total dos olhos e os barbilhões alongados. Além disso, a presença de uma dobra adiposa bem desenvolvida nos adultos pode indicar uma adaptação distintiva, adquirida por neotenia, para enfrentar as condições alimentares escassas do seu habitat hipógeo.

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RESUMO

Trichomycterus dali, new species, is described from flooded limestone caves in Serra da Bodoquena karst area, State of Mato Grosso do Sul, Central Brazil. The new species is diagnosed by a unique character in the genus, the presence of conspicuous, ridge-like adipose folds lining dorsally throughout the body. Trichomycterus dali can be further distinguished readily from epigean congeners by the reduction of eyes and skin pigmentation (except for T. gorgona), and from remaining congeners (i.e., all hypogean plus T. gorgona) by the total loss of eyes, not visible externally (except for T. sandovali and T. spelaeus). Other diagnostic features includes very long barbels, especially the nasal (99.3-143.5 percent HL) and the maxillary (97.0-131.3 percent HL), pectoral-fin ray count reaching I,9 and a unique cranial fontanel with a conspicuous constriction on the meeting point of supraoccipital and the two frontal bones. The troglobitic status of the species is suggested by the presence of troglomorphisms on an advanced degree, especially the reduction of skin pigmentation, the total loss of eyes and the enlarged barbels. In addition, the presence of a well developed adipose fold in adults may indicate a distinctive adaptation acquired by neoteny to withstand the food scarce conditions of its hypogean habitat.(AU)

Trichomycterus dali, espécie nova, é descrita de cavernas calcárias alagadas na área cárstica da Serra da Bodoquena, estado do Mato Grosso do Sul, Brasil central. A nova espécie é diagnosticada por um caráter único no gênero, a presença de dobras adiposas conspícuas, em forma de crista, passando por toda a região dorsal do corpo. Trichomycterus dali pode ser ainda diferenciada facilmente de suas congêneres epígeas pela redução dos olhos e da pigmentação cutânea (exceto para T. gorgona), e das congêneres restantes (isto é, todas as hipógeas mais T. gorgona) pela perda total dos olhos, não visíveis externamente (exceto para T. sandovali e T. spelaeus). Outras características diagnósticas incluem barbilhões muito longos, especialmente o nasal (99,3-143,5 por cento do comprimento da cabeça) e o maxilar (97,0-131,3 por cento do comprimento da cabeça), contagem de raios da nadadeira peitoral atingindo I,9 e uma fontanela cranial única com uma constrição conspícua no ponto de encontro do supraoccipital e dos dois ossos frontais. O status troglóbio da espécie é sugerido pela presença de troglomorfismos em avançado grau, especialmente a redução da pigmentação cutânea, a perda total dos olhos e os barbilhões alongados. Além disso, a presença de uma dobra adiposa bem desenvolvida nos adultos pode indicar uma adaptação distintiva, adquirida por neotenia, para enfrentar as condições alimentares escassas do seu habitat hipógeo.(AU)

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