New records of pseudoscorpions (Arachnida, Pseudoscorpiones) from the Caatinga biome, Brazil: a checklist and a map of species richness distribution

Abstract

In the course of ongoing research on the pseudoscorpion fauna in the northeastern region of Brazil, we compiled nine pseudoscorpion species with three of them, Geogarypus amazonicus, Apolpium ecuadorense, and Pachyolpium furculiferum, recorded for the first time from the Caatinga biome. Ecological comments are included, and the presence of G. amazonicus is discussed. Additionally, an updated checklist of all pseudoscorpion species and a map of the distribution of species richness for all biomes of Brazil are presented.

The first troglobitic Pseudochthonius Balzan, 1892 (Pseudoscorpiones, Chthoniidae) from the karst area of Serra do Ramalho, Brazil: a threatened species

“…It occurs in several regions of the world, with the greatest diversity in the USA (147), Italy (84), Spain (59), Australia (36) (Harvey 2013). In Brazil, the family Chthoniidae has 29 species in eleven genera, Heterolophus Tömösváry, 1884, Tridenchthonius Balzan, 1887, Lechthyia Balzan, 1892, Pseudochthonius Balzan, 1892, Compsaditha Chamberlin, 1929, Tyrannochthonius Chamberlin, 1929, Austrochthonius Chamberlin, 1929, Soroditha Chamberlin & Chamberlin, 1945, Neoditha Feio, 1945, Cryptoditha Chamberlin & Chamberlin, 1945and Lagynochthonius Beier, 1951(Harvey 2013Lira et al 2020).…”

“…The genus Pseudochthonius is characterized by the absence of an intercoxal tubercle, the presence of coxal spines on coxae I and II, and in most cases, having strongly sigmoid palpal chelal fingers (Muchmore 1986;Mahnert and Adis 2002). Pseudochthonius is known from Asia (one species from Saudi Arabia), Africa (five species distributed in the Republic of Congo and Ivory Coast), Central America [six living species of which two are troglobites: P. troglobius Muchmore, 1986 from Mexico (Muchmore 1986) and P. arubensis Wagenaar-Hummelinck, 1948, from the Netherlands Antilles (Wagenaar-Hummelinck1948) and one fossil species (Schawaller 1980)] and South America, with nine species in Brazil (Harvey 2013;Mahnert et al 2014;Lira et al 2020), followed by Ecuador with three, Venezuela with two and Uruguay with one species (Harvey 2013). In Brazil, two Pseudochthonius species are troglobites (Mahnert 2001), i.e., they have exclusive populations in the hypogean environment: P. strinatii Beier, 1969 andP.…”