Corresponding author: Brogan L. Pett (
Academic editor: Danilo Harms
A new genus and two new species of ant-resembling castianeirine spiders are described from the Neotropics.
The subfamily
Castianeirines are notorious for having highly conserved genitalic characters (
In the current study, two new castianeirine species are described from Bolivia and Paraguay. These species share a combination of several somatic and genitalic characters with
Material is preserved in 70% ethanol. The epigyne was dissected using a custom-made hooked pin and digested by submersion in a glass vial filled with lactic acid, which was placed in boiling water for around thirty minutes. The cleared epigyne was temporarily prepared on a slide and examined with a compound microscope. Examinations were carried out with an AmScope ZM-4T stereomicroscope or an Olympus BX61. Images were taken using either a Leica M125C automontage system or an Olympus BX61 with a DP74 camera. All images were z-stacked, with between 10–30 images merged into a single photomontage, using Helicon Focus 6.7 (
The following indices are used following
Leg spination follows
Arachnological collections are abbreviated as follows (curators in parenthesis):
Nomenclatural acts. This published work and the nomenclatural acts it contains have been registered in Zoobank:
The ecoregion affinities of the species were investigated by visualizing the coordinates and a shapefile of the regionalization of Neotropical ecosystems by
Ecoregion affinities of
The genus name is a patronym in honor of Cristian Grismado, arachnologist of Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”. The letter ‘x’ is taken from the suffix of the genus
Considering carapace and abdomen shape, arrangement and number of tibia I spines, and the petiolated pedicel,
Some species of
Other genera with a recurved
Small, slender spiders with adults between 3.17 mm and 6.20 mm total length. Carapace generally ellipsoid, truncated at posterior margin, with distinct subrectangular cephalic region (more rectangular in females). Carapace sloping very gently towards highest point, at posterior half of the fovea.
The species of this genus are currently known from the Humid Chaco in southwestern Paraguay and two savanna locations in the area of Chiquitano dry forest and Moxos Plains Flooded Savannas in Bolivia. Judging from observations of live individuals (
1 | Males | 2 |
– | Females (that of |
5 |
2 | Coxae II–III pale or light yellow, others dark | 3 |
– | Coxae II–IV pale or light yellow, other dark | |
3 | Anterior tibia spination 3-2 | 4 |
– | Anterior tibia spination 3-3 | |
4 | Embolus with three coils | |
– | Embolus with four and a half coils | |
5 | Anterior tibia spination 3-2 | 6 |
– | Anterior tibia spination 3-3 | |
6 | COs anterolateral of |
|
– | COs far anterior of |
Separated from congeners by: embolus that coils four times (vs. three, four-and-a-half, or five) (Figs
The species epithet is a noun in apposition, and refers to the Guarani word for Wetland “
Habitus shape, leg formula, spination and general color pattern as in female, male carapace brighter, primarily orangish-brown. Dorsal scutum large, around 3/4 of
This species is only known from the type locality in Estancia Santa Ana, Ñeembucú wetland complex, Paraguay. According to the ecoregion delineation by
Separated from congeners by: coxae IV in male light (vs. dark) (Figs
The species epithet is a genitive patronym in honor of German arachnologist Tobias Bauer, of
This species is only known from the type locality in Espiritu, José Ballivián province, Beni Department, Bolivia. According to the ecoregion delineation by
Separated from congeners by: an embolus that coils three times (vs. between four and five times);
See:
Epigeal in Cerrado-like grassland or savanna habitats. According to Navarro and Ferreira (2011), the type locality of this species is situated in Chiquitano forest, while
Separated from congeners by: pedipalp with four and a half coils (vs. three, four or five);
See: Pett (2021).
Epigeal in savanna-like wetland in the Humid Chaco area.
All
The conservation value of such regions is barely understood in terms of their invertebrate taxa (
Extensive thanks are due to Rufus Wyer, co- collector of the type specimens of the type species. Additional thanks are due to Varvara Vladimirova (Université Laval) and Jack McBride for assistance in the field during the pitfall trapping project in Paraguay. Thanks also to Fundación Para La Tierra for supporting the project through provision of resources during the pitfall trapping project in Paraguay, to Don Odilon Barrios for allowing the pitfall trap project at Estancia Santa Ana, and to the staff at the Coronel Alberto Torres Nuñez for access to the Regimiento de Caballeria No 2 “Colonel Felipe Toledo”. The Ministerio del Ambiente y Desarrollo Sostenible granted research permits to the CCPLT for Paraguayan specimens. Thanks to Jorge Ayala Damian Santacruz for assisting in Guaraní translation. Thanks to Tobias Bauer and Hubert Höfer (both