Bonnetina obscura, Johannsen, 1912

BONNETINA OBSCURA ( SIMON, 1891) COMB. NOV., NOMEN DUBIUM

( FIG. 13; TABLE 2)

urn:lsid:zoobank.org:act:0EECE282-C429-403D-9CC8-B3206A006596

Cyclosternum obscurum Simon, 1891: 331 . Vol, 2001: 14, fig. 11.

Davus obscurus – Schmidt, 2005: 14, fig. 10.

Type locality: Mexico Material examined (n = 1): ♀ holotype (MNHNP-4813) . Mexico (with no additional details).

Remarks: Cyclosternum Ausserer, 1871 , is one of the most poorly understood genera in Theraphosinae. Its type species Cyclosternum schmardae Ausserer, 1871 , was described based on a single female from a very poorly defined locality: Cordilleren 4000–5000’ (The Cordilleras, at 4000–5000 feet). Not even the country or the geographic area was mentioned in the original description. After this, Cyclosternum has become a ‘dump’ genus, as at least species of 12 genera have been once placed in it ( World Spider Catalog, 2016). Contemporary diagnoses of the genus have been based on material doubtfully identified. For example, in his mygalomorph revision, Raven (1985) did not examine the type specimen of C. schmardae , but others that he considered congeneric to Cyclosternum . Likewise, in the most complete Theraphosinae revision to the present, Pérez-Miles et al. (1996) used a male and a female, which were probably erroneously assigned to the types of C. schmardae ( Ortiz, 2008) . Most of the 12 species that are still located in Cyclosternum are from South America. The exceptions are three Mexican species, including C. obscurum . The holotype of C. obscurum ( Fig. 13) is a small-sized tarantula that possesses a central patch of urticating hairs type III on the abdomen, and a single spermatheca with a very similar shape to those of B. aviae and other morphologically similar Bonnetina species (see below) with domiform-low spermatheca (see Estrada-Alvarez & Locht, 2011). These characters allow the species to be placed in Bonnetina , but without more data or an accurate type locality, a large degree of uncertainty remains as to its species-level identity. Transferring C. obscurum to Bonnetina locates the species in the right group, and declaring it a nomen dubium accounts for the uncertainty as to its identity and increases taxonomic stability.