RESUMEN
The genus Chisosa Huber, 2000 previously included only three species of small to tiny North American and Caribbean spiders that are rare in collections and poorly studied. Originally placed in the subfamily Ninetinae, Chisosa is currently considered a representative of Arteminae, close to the North American genus Physocyclus Simon, 1893. This placement has been suggested by molecular data, and it affects the interpretation of morphological characters that were originally thought to support the monophyly of Chisosa: they are shared with Physocyclus and thus plesiomorphic for Chisosa. Here we describe a new species from Mexico, C. calapa sp. nov., and restudy in detail the morphology (incl. ultrastructure) of the type species C. diluta (Gertsch & Mulaik, 1940) and of C. caquetio Huber, 2019, based on newly collected material. We document further similarities with Physocyclus but find only weak morphological support for the monophyly of Chisosa (body size reduction and short legs). In addition, we document surprisingly large genetic distances among C. caquetio specimens from Curaao (>14% CO1 K2P distances), possibly indicating species limits. Finally, we propose that the Dominican amber genus Serratochorus Wunderlich, 1988, based on a single male specimen, is also phylogenetically close to Chisosa and should be included in future studies on these enigmatic spiders.
Asunto(s)
Arañas , Masculino , Animales , México , Distribución Animal , Estructuras Animales/anatomía & histología , Tamaño de los ÓrganosRESUMEN
The Venezuelan genus Stenosfemuraia González-Sponga, 1998 is revised, with redescriptions of its three named species: S. parva González-Sponga, 1998 (type species); S. cuadrata González-Sponga, 2005; and S. pilosa (González-Sponga, 2005) n. comb. The latter species was originally described as Codazziella pilosa, and six years later again as Chichiriviche costanero González-Sponga, 2011 (n. syn.). The monotypic genera Codazziella González-Sponga, 2005 and Chichiriviche González-Sponga, 2011 are thus newly synonymized with Stenosfemuraia. The genus appears restricted to the Cordillera de la Costa region where the spiders occupy near-ground microhabitats in medium to high elevation forests.
Asunto(s)
Arañas , Animales , BosquesRESUMEN
The Atlantic Forest along the eastern South American coast is widely recognized as a hotspot with extreme levels of diversity, endemism, and threat. A megatransect study (2003-2015) focusing on pholcid spiders and covering 48 localities across a large part of the Brazilian Atlantic Forest resulted in 132 morphospecies, of which 81% were new to science. The present paper deals with the species of Carapoia González-Sponga, 1998 collected during this campaign. The endemism level is 100%, i.e. all 26 species of Carapoia in the Atlantic Forest are not known from (and not likely to occur) anywhere else. While few species (all of them with non-overlapping ranges) occur in the most southern and northern regions, the central region (between Rio Doce and Rio Paraguaçu; largely equivalent to what has been called the 'Bahia refuge') is characterized by high diversity and up to five species per locality. The following species are newly described (from South to North): C. voltavelha (Santa Catarina); C. macacu, C. divisa (Rio de Janeiro); C. nairae, C. capixaba, C. mirim, C. patafina (Espírito Santo); C. pau, C. gracilis, C. zumbii, C. dandarae, C. marceloi, C. viridis, C. jiboia, C. carvalhoi, C. carybei (Bahia); C. alagoas (Alagoas); C. saltinho, C. abdita (Pernambuco); C. septentrionalis (Pernambuco to Rio Grande do Norte). New records and amendments are given for most previously described Atlantic Forest species.
Asunto(s)
Arañas/clasificación , Animales , Biodiversidad , Brasil , Femenino , Masculino , Bosque Lluvioso , Especificidad de la Especie , Arañas/anatomía & histologíaRESUMEN
In an ongoing mega-transect project that aims at analyzing pholcid spider diversity and distribution in the Atlantic Forest of Brazil, many species appear restricted to small geographic ranges. Of the 84 species collected between 2003 and 2011 at 17 sites between Bahia and Santa Catarina, 51 species (61%) were found at only one locality. The present paper focuses on such species in the genus Mesabolivar, and compares diversity and distribution patterns of this genus within and outside the Atlantic Forest. The percentage of species known from single localities is higher in the Atlantic Forest (34 of 52 species; 65%) than outside the Atlantic Forest (10 of 25; 40%). Distribution rages of species in the Atlantic Forest are significantly smaller than of species outside the Atlantic Forest (mean maximum distances between localities: 184 versus 541 km; medians: 10 km versus 220 km). The following species are newly described (arranged from north to south), each currently known from the respective type locality only: M. caipora; M. kathrinae; M. bonita; M. pau (Bahia); M. monteverde; M. perezi (Espírito Santo); M. giupponii; M. goitaca; M. sai (Rio de Janeiro); M. tamoio; M. unicornis; M. gabettae; M. inornatus (São Paulo); M. itapoa (Santa Catarina).
Asunto(s)
Arañas/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Brasil , Ecosistema , Femenino , Bosques , Masculino , Tamaño de los Órganos , Arañas/anatomía & histología , Arañas/crecimiento & desarrolloRESUMEN
Hypotheses regarding the function of elaborate male genitalia were tested in a sample of insects and spiders by comparing their allometric values (slopes in log-log regressions on indicators of body size) with those of other body parts. Male genitalia consistently had lower slopes than other body parts. Perhaps as a consequence of this pattern, genitalic size also tended, though less consistently, to have lower coefficients of variation than did the size of other body parts. The morphological details of coupling between males and females in several species clearly indicated that selection favoring mechanical fit is not responsible for these trends. Sexual selection on male courtship structures that are brought into contact with females in precise ways may favor relatively low allometric values, in contrast to the high values seen in the other sexually selected characters (usually visual display devices) that have been studied previously, because a female's own size will influence her perception of the contact courtship devices of a male.