I am a biologist and my research interests stem from my desire to understand fundamental aspects of biological diversity. These aspects include the relationships of organisms and their morphological complexity. As an arachnologist my current focus is on the Systematics of Synspermiata spiders families. Most of my works are aimed at studying these spider families worldwide, as well as understanding the morphological diversity of their species. Supervisors: Alexandre Bonaldo, Antonio Brescovit, and Giraldo Alayon Phone: +491791447568
The species Cithaeron praedonius O. P.-Cambridge is recorded from eastern Cuba. This is the first... more The species Cithaeron praedonius O. P.-Cambridge is recorded from eastern Cuba. This is the first record of the family Cithaeronidae in the Caribbean Region. The presence in Cuba of this species is an accidental introduction, but its source is unknown.
The genus Caponina Simon, 1891 comprises eleven species of medium-sized, soil-dwelling caponiids.... more The genus Caponina Simon, 1891 comprises eleven species of medium-sized, soil-dwelling caponiids. Most members of Caponina have six eyes, but some have five, four, three or two eyes (Brignoli 1977, Platnick 1994). The genus is widespread in South and Central America (Platnick 2012). To date, only three species have been recorded from Brazil: Caponina alegre Platnick, 1994 from the state of Rio Grande do Sul, C. notabilis (Mello-Leitão, 1939) from the states of Paraná and Rio Grande do Sul, and C. tijuca Platnick, 1994 from the state of Rio de Janeiro (Platnick 1994). In this paper we describe a new species from the state of Pará, in Brazilian Amazonia. Caponina papamanga new species was collected during the “Butantan na Amazonia” project, founded by the Instituto Butantan. The phylogenetic relationships of C. papamanga could not be studied, but the greatly elongated embolus, the dorsal tubercle on the palpal femur (Figs. 7, 9) and the massive epigynal sclerotizations (Fig. 10) sugge...
Información del artículo Current taxonomic status of the family Caponiidae (Arachnida, Araneae) i... more Información del artículo Current taxonomic status of the family Caponiidae (Arachnida, Araneae) in Cuba with the description of two new species.
Four new Colombian species of the spider genus Medionops Sánchez-Ruiz & Brescovit, 2017 are descr... more Four new Colombian species of the spider genus Medionops Sánchez-Ruiz & Brescovit, 2017 are described and illustrated: M. carolinae sp. nov. (male and female) from Boyacá department, M. cauca sp. nov. (male) from Cauca department, M. luiscarlosi sp. nov. (male and female) from Caldas department and M. santarosa sp. nov. (male) from Risaralda department. Additionally, the distribution of the type species of M. blades Sánchez-Ruiz & Brescovit, 2017, previously known only from Bogotá, Cundinamarca department, is extended to several localities in the Boyacá department. An updated identification key for all Medionops species is provided.
The spider genus Nops MacLeay is revised, with redescriptions of 22 previously known species and ... more The spider genus Nops MacLeay is revised, with redescriptions of 22 previously known species and descriptions of 12 new species. A new diagnosis for the genus is provided and keys to separate the species are proposed. After this revision Nops includes 34 extant species, thereof 15 (44%) occur in the Caribbean Islands, four (12%) in Central America and 15 (44%) in South America. Females of Nops meridionalis Keyserling and Nops gertschi Chickering are found and described for the first time. Three new synonymies are proposed: Nops virginicus Sánchez–Ruiz with Nops blandus Bryant, Nops craneae Chickering with Nops maculatus Simon and Nops proseni Birabén with Nops farhati Prosen. Four species are considered inquerenda: Nops anisitsi Strand, Nops bellulus Chamberlin, Nops branicki (Taczanowski) and Nops glaucus Hasselt. The following new species are described: N. jaragua n. sp., N. navassa n. sp., and N. pallidus n. sp. from the Caribbean region; N. campeche n. sp. and N. tico n. sp. from Central America, and N. alexenriquei n. sp., N. amazonasn. sp., N. bahia n. sp., N. ipojuca n. sp., N. itapetinga n. sp., N. minas n. sp. and N. pocone n. sp. from South America. New geographical records and distribution maps are provided for all species, with illustrations and reviewed diagnoses. The Nops species are restricted to the Neotropical region, from the Caribbean Islands and Mexico to the north of Argentina. The highest species richness is concentrated in the Wider Caribbean Region, including Central America and the north of Colombia and Venezuela where 64.7% of the species occur. Endemism in the Caribbean islands is very high; most of these species are single island endemics. A cladistic analysis, based on morphological data, was executed to test the monophyly of the genus. This is the first cladistic analysis of Caponiidae, and it includes besides the Nops species, 1) the six other species that were transferred from Nops, now in the genera Orthonops, Cubanops, Tarsonops and Medionops, and 2) Nopsides ceralbonus Chamberlin and Nyetnops guarani Platnick & Lise. Therefore, representatives of all known Nopinae genera are included in the ingroup. The data matrix comprises 41 taxa scored for 47 morphological characters. The analyses under equal weights resulted in six equally parsimonious trees of 99 steps. All these trees are congruent with a unique hypothesis for Nopinae genera. Thus, all topological differences among the most parsimonious trees were the consequence of different hypotheses of relationships within Nops. The same result was also found under implied weighting with constants of concavity k = 2 to 13, where the topology of all trees was congruent for a single Nopinae genera hypothesis, but relationships within Nops were not resolved. All analysis under equal and implied weights recovered the monophyly of Nops with high support values, but internal clades within the genus showed low branch supports. Our results thus suggest that to resolve the internal relationships of Nops, studies based on molecular evidence are necessary to counteract the deficit of morphological data. The hypothesis obtained for Nopinae showed high branch support values for most of clades, corroborating all the transfers made from Nops. Medionops was recovered as the sister group of Nops with high support values. Nops, Medionops and Nopsides form a closely related, distinct spider group among nopine, supported by five unambiguous synapomorphies. Two of these synapomorphies could be functionally related: the presence of an arolium on the anterior pretarsi and the elongated and dorsally reflexed unpaired claw on the anterior legs. Nopsides appears to be a genus with apomorphic characters, presenting highly modified legs, but lacking the crista and gladius, and gaining a pair of anterior lateral eyes. Nyetnops is sister to all other nopine genera. Our results identified the necessity of further studies on nopine leg structures (arolium, crista, gladius and adesmatic joints) to improve understanding of the phylogenetic relationships of Nopinae genera.
Four new species of Syspira Simon, 1895 are described: Syspira cimitarra sp. nov., Syspira jimmyi... more Four new species of Syspira Simon, 1895 are described: Syspira cimitarra sp. nov., Syspira jimmyi sp. nov., Syspira me-dialuna sp. nov. and Syspira agujas sp. nov., all endemic in the Dominican Republic.
The new genus Medionops is proposed for a group of caponiid spiders found in South America and Pa... more The new genus Medionops is proposed for a group of caponiid spiders found in South America and Panama. Nops simla Chickering and Nops cesari Dupérré are transferred to this new genus. Additionally, five new species are described: the type species Medionops blades n. sp. from Colombia; Medionops claudiae n. sp., Medionops murici n. sp. and Medionops ramirezi n. sp. from Brazil; and Medionops tabay n. sp. from Venezuela. All of these species belong to the subfamily Nopinae and have the three membranous translucent modifications found in some other nopine genera. However, in this new genus, the ventral translucent keel on the anterior metatarsi (crista herein) is very short, almost unnoticeable or even absent in some species. The translucent extension of the membrane between the anterior metatarsi and tarsi (gladius herein) retains the same shape, but it is absent in M. murici n. sp. Also, Medionops n. gen. species have an unpaired claw on all tarsi, which is elongate and dorsally reflexed, and is associated with a membranous globose translucent lobe (arolium herein); a structure present only in Nops MacLeay and Nopsides Chamberlin. Beside the characteristics mentioned above, members of this new genus differ from other nopine in the shape of labium and endites and in the conformation of male and female genitalia. The three membranous translucent modifications on legs of some nopine genera are discussed and their terminologies are standardized.
New members of the spider family Caponiidae from Brazil and Chile are presented. Three new specie... more New members of the spider family Caponiidae from Brazil and Chile are presented. Three new species in previously known genera are described: Taintnops paposo sp. n. from Chile, and the Brazilian Tisentnops mineiro sp. n. and Tisentnops onix sp. n., both belonging to a genus known only from its damaged type. Additionally, two new non–nopine Brazilian genera are proposed: Nasutonops gen. n. including three new species: N. chapeu sp. n., N. sincora sp. n. and N. xaxado sp. n.; and Carajas gen. n., known only from the type species C. paraua sp. n. Both new genera have entire, rather than sub-segmented tarsi. Therefore , they are not included in the caponiid subfamily Nopinae. Nasutonops gen. n. is characterized by the presence of a projected clypeal horn, unique among caponiids. Additionally, the first blind caponiids are described: Tisentnops mineiro sp. n. from the state of Minas Gerais and Carajas paraua sp. n. from the state of Pará. Both of these species are found only in caves and completely lack eyes.
A synopsis of Caribbean filistatid diversity is recorded herein. A new genus, Antilloides, is pro... more A synopsis of Caribbean filistatid diversity is recorded herein. A new genus, Antilloides, is proposed for five new species exclusively found in the Antilles: A. abeli n. sp., A. cubitas n. sp., and A. mesoliticus n. sp. from Cuba; A. haitises n. sp. from the Dominican Republic; and A. zozo n. sp. from the U. S. Virgin Islands and Puerto Rico. The genus Filistatoides is revised and includes four species: the type species F. insignis F.O.P. Cambridge, which occurs only in Guatemala; the female is described here for the first time; F. polita Franganillo sp. reval., comb. nov., which occurs only in Cuba; F. xichu n. sp. described from Mexico; and F. milloti (Zapfe) which does not appear to belong to the genus based on morphological structures. Additionally, Kukulcania isolinae Alayón is synonymized with Kukulcania hibernalis (Hentz), and new records of its distribution are included for the Greater and Lesser Antilles.
Alexander Sánchez-Ruiz A new species of the spider genus Nops MacLeay, 1839 is herein described f... more Alexander Sánchez-Ruiz A new species of the spider genus Nops MacLeay, 1839 is herein described from Jarabacoa, La Vega province, Dominican Republic. The finding of this species elevates to five the number of species of Caponiidae present in The Hispaniola. Some aspects about the taxonomy of the genus Nops in the West Indies are discussed.
The species Cithaeron praedonius O. P.-Cambridge is recorded from eastern Cuba. This is the first... more The species Cithaeron praedonius O. P.-Cambridge is recorded from eastern Cuba. This is the first record of the family Cithaeronidae in the Caribbean Region. The presence in Cuba of this species is an accidental introduction, but its source is unknown.
The genus Caponina Simon, 1891 comprises eleven species of medium-sized, soil-dwelling caponiids.... more The genus Caponina Simon, 1891 comprises eleven species of medium-sized, soil-dwelling caponiids. Most members of Caponina have six eyes, but some have five, four, three or two eyes (Brignoli 1977, Platnick 1994). The genus is widespread in South and Central America (Platnick 2012). To date, only three species have been recorded from Brazil: Caponina alegre Platnick, 1994 from the state of Rio Grande do Sul, C. notabilis (Mello-Leitão, 1939) from the states of Paraná and Rio Grande do Sul, and C. tijuca Platnick, 1994 from the state of Rio de Janeiro (Platnick 1994). In this paper we describe a new species from the state of Pará, in Brazilian Amazonia. Caponina papamanga new species was collected during the “Butantan na Amazonia” project, founded by the Instituto Butantan. The phylogenetic relationships of C. papamanga could not be studied, but the greatly elongated embolus, the dorsal tubercle on the palpal femur (Figs. 7, 9) and the massive epigynal sclerotizations (Fig. 10) sugge...
Información del artículo Current taxonomic status of the family Caponiidae (Arachnida, Araneae) i... more Información del artículo Current taxonomic status of the family Caponiidae (Arachnida, Araneae) in Cuba with the description of two new species.
Four new Colombian species of the spider genus Medionops Sánchez-Ruiz & Brescovit, 2017 are descr... more Four new Colombian species of the spider genus Medionops Sánchez-Ruiz & Brescovit, 2017 are described and illustrated: M. carolinae sp. nov. (male and female) from Boyacá department, M. cauca sp. nov. (male) from Cauca department, M. luiscarlosi sp. nov. (male and female) from Caldas department and M. santarosa sp. nov. (male) from Risaralda department. Additionally, the distribution of the type species of M. blades Sánchez-Ruiz & Brescovit, 2017, previously known only from Bogotá, Cundinamarca department, is extended to several localities in the Boyacá department. An updated identification key for all Medionops species is provided.
The spider genus Nops MacLeay is revised, with redescriptions of 22 previously known species and ... more The spider genus Nops MacLeay is revised, with redescriptions of 22 previously known species and descriptions of 12 new species. A new diagnosis for the genus is provided and keys to separate the species are proposed. After this revision Nops includes 34 extant species, thereof 15 (44%) occur in the Caribbean Islands, four (12%) in Central America and 15 (44%) in South America. Females of Nops meridionalis Keyserling and Nops gertschi Chickering are found and described for the first time. Three new synonymies are proposed: Nops virginicus Sánchez–Ruiz with Nops blandus Bryant, Nops craneae Chickering with Nops maculatus Simon and Nops proseni Birabén with Nops farhati Prosen. Four species are considered inquerenda: Nops anisitsi Strand, Nops bellulus Chamberlin, Nops branicki (Taczanowski) and Nops glaucus Hasselt. The following new species are described: N. jaragua n. sp., N. navassa n. sp., and N. pallidus n. sp. from the Caribbean region; N. campeche n. sp. and N. tico n. sp. from Central America, and N. alexenriquei n. sp., N. amazonasn. sp., N. bahia n. sp., N. ipojuca n. sp., N. itapetinga n. sp., N. minas n. sp. and N. pocone n. sp. from South America. New geographical records and distribution maps are provided for all species, with illustrations and reviewed diagnoses. The Nops species are restricted to the Neotropical region, from the Caribbean Islands and Mexico to the north of Argentina. The highest species richness is concentrated in the Wider Caribbean Region, including Central America and the north of Colombia and Venezuela where 64.7% of the species occur. Endemism in the Caribbean islands is very high; most of these species are single island endemics. A cladistic analysis, based on morphological data, was executed to test the monophyly of the genus. This is the first cladistic analysis of Caponiidae, and it includes besides the Nops species, 1) the six other species that were transferred from Nops, now in the genera Orthonops, Cubanops, Tarsonops and Medionops, and 2) Nopsides ceralbonus Chamberlin and Nyetnops guarani Platnick & Lise. Therefore, representatives of all known Nopinae genera are included in the ingroup. The data matrix comprises 41 taxa scored for 47 morphological characters. The analyses under equal weights resulted in six equally parsimonious trees of 99 steps. All these trees are congruent with a unique hypothesis for Nopinae genera. Thus, all topological differences among the most parsimonious trees were the consequence of different hypotheses of relationships within Nops. The same result was also found under implied weighting with constants of concavity k = 2 to 13, where the topology of all trees was congruent for a single Nopinae genera hypothesis, but relationships within Nops were not resolved. All analysis under equal and implied weights recovered the monophyly of Nops with high support values, but internal clades within the genus showed low branch supports. Our results thus suggest that to resolve the internal relationships of Nops, studies based on molecular evidence are necessary to counteract the deficit of morphological data. The hypothesis obtained for Nopinae showed high branch support values for most of clades, corroborating all the transfers made from Nops. Medionops was recovered as the sister group of Nops with high support values. Nops, Medionops and Nopsides form a closely related, distinct spider group among nopine, supported by five unambiguous synapomorphies. Two of these synapomorphies could be functionally related: the presence of an arolium on the anterior pretarsi and the elongated and dorsally reflexed unpaired claw on the anterior legs. Nopsides appears to be a genus with apomorphic characters, presenting highly modified legs, but lacking the crista and gladius, and gaining a pair of anterior lateral eyes. Nyetnops is sister to all other nopine genera. Our results identified the necessity of further studies on nopine leg structures (arolium, crista, gladius and adesmatic joints) to improve understanding of the phylogenetic relationships of Nopinae genera.
Four new species of Syspira Simon, 1895 are described: Syspira cimitarra sp. nov., Syspira jimmyi... more Four new species of Syspira Simon, 1895 are described: Syspira cimitarra sp. nov., Syspira jimmyi sp. nov., Syspira me-dialuna sp. nov. and Syspira agujas sp. nov., all endemic in the Dominican Republic.
The new genus Medionops is proposed for a group of caponiid spiders found in South America and Pa... more The new genus Medionops is proposed for a group of caponiid spiders found in South America and Panama. Nops simla Chickering and Nops cesari Dupérré are transferred to this new genus. Additionally, five new species are described: the type species Medionops blades n. sp. from Colombia; Medionops claudiae n. sp., Medionops murici n. sp. and Medionops ramirezi n. sp. from Brazil; and Medionops tabay n. sp. from Venezuela. All of these species belong to the subfamily Nopinae and have the three membranous translucent modifications found in some other nopine genera. However, in this new genus, the ventral translucent keel on the anterior metatarsi (crista herein) is very short, almost unnoticeable or even absent in some species. The translucent extension of the membrane between the anterior metatarsi and tarsi (gladius herein) retains the same shape, but it is absent in M. murici n. sp. Also, Medionops n. gen. species have an unpaired claw on all tarsi, which is elongate and dorsally reflexed, and is associated with a membranous globose translucent lobe (arolium herein); a structure present only in Nops MacLeay and Nopsides Chamberlin. Beside the characteristics mentioned above, members of this new genus differ from other nopine in the shape of labium and endites and in the conformation of male and female genitalia. The three membranous translucent modifications on legs of some nopine genera are discussed and their terminologies are standardized.
New members of the spider family Caponiidae from Brazil and Chile are presented. Three new specie... more New members of the spider family Caponiidae from Brazil and Chile are presented. Three new species in previously known genera are described: Taintnops paposo sp. n. from Chile, and the Brazilian Tisentnops mineiro sp. n. and Tisentnops onix sp. n., both belonging to a genus known only from its damaged type. Additionally, two new non–nopine Brazilian genera are proposed: Nasutonops gen. n. including three new species: N. chapeu sp. n., N. sincora sp. n. and N. xaxado sp. n.; and Carajas gen. n., known only from the type species C. paraua sp. n. Both new genera have entire, rather than sub-segmented tarsi. Therefore , they are not included in the caponiid subfamily Nopinae. Nasutonops gen. n. is characterized by the presence of a projected clypeal horn, unique among caponiids. Additionally, the first blind caponiids are described: Tisentnops mineiro sp. n. from the state of Minas Gerais and Carajas paraua sp. n. from the state of Pará. Both of these species are found only in caves and completely lack eyes.
A synopsis of Caribbean filistatid diversity is recorded herein. A new genus, Antilloides, is pro... more A synopsis of Caribbean filistatid diversity is recorded herein. A new genus, Antilloides, is proposed for five new species exclusively found in the Antilles: A. abeli n. sp., A. cubitas n. sp., and A. mesoliticus n. sp. from Cuba; A. haitises n. sp. from the Dominican Republic; and A. zozo n. sp. from the U. S. Virgin Islands and Puerto Rico. The genus Filistatoides is revised and includes four species: the type species F. insignis F.O.P. Cambridge, which occurs only in Guatemala; the female is described here for the first time; F. polita Franganillo sp. reval., comb. nov., which occurs only in Cuba; F. xichu n. sp. described from Mexico; and F. milloti (Zapfe) which does not appear to belong to the genus based on morphological structures. Additionally, Kukulcania isolinae Alayón is synonymized with Kukulcania hibernalis (Hentz), and new records of its distribution are included for the Greater and Lesser Antilles.
Alexander Sánchez-Ruiz A new species of the spider genus Nops MacLeay, 1839 is herein described f... more Alexander Sánchez-Ruiz A new species of the spider genus Nops MacLeay, 1839 is herein described from Jarabacoa, La Vega province, Dominican Republic. The finding of this species elevates to five the number of species of Caponiidae present in The Hispaniola. Some aspects about the taxonomy of the genus Nops in the West Indies are discussed.
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