''Acanthogonatus hualpen'' is a

mygalomorph The Mygalomorphae, or mygalomorphs, are an infraorder of spiders, and comprise one of three major groups of living spiders with over 3000 species, found on all continents except Antarctica. Many members are known as trapdoor spiders due to t ...

spider of

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

, named after its type locality: Hualpén, Concepción, Bío Bío Region.Goloboff, Pablo A. "A revision of the South American spiders of the family Nemesiidae (Araneae, Mygalomorphae). Part 1, Species from Peru, Chile, Argentina, and Uruguay. Bulletin of the AMNH; no. 224." (1995). Males can be distinguished from those of '' A. nahuelbuta'' and '' A. patagallina'' by the shaped of the bulb's apex, and by the palpal

tibia The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects ...

being wide in the basal two-thirds (tapering abruptly at the apex) with thickened

setae In biology, setae (singular seta ; from the Latin word for " bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. ...

along the apical one-third of the retrolateral face (instead of two-thirds).

Description

*Male: total length ; cephalothorax length , width ; cephalic region length , width ; medial ocular quadrangle (OQ) length , width ; labium length , width ;

sternum The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Sha ...

length , width . Its labium and maxillae possess no cuspules; its

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. T ...

e have thickened setae on their anterior inner corner. A serrula is present. Its sternum and sigilla resemble those in ''A. nahuelbuta''.

Chelicerae The chelicerae () are the mouthparts of the subphylum Chelicerata, an arthropod group that includes arachnids, horseshoe crabs, and sea spiders. Commonly referred to as " jaws", chelicerae may be shaped as either articulated fangs, or similarl ...

: rastellum is absent. Cheliceral

tumescence Tumescence is the quality or state of being tumescent or swollen. Tumescence usually refers to the normal engorgement with blood (vascular congestion) of the erectile tissues, marking sexual excitation, and possible readiness for sexual activity ...

is small, with a ventral protuberance. Leg I and its tibial apophysis is similar to that of ''A. Nahuelbuta'', while its

metatarsus The metatarsal bones, or metatarsus, are a group of five long bones in the foot, located between the tarsal bones of the hind- and mid-foot and the phalanges of the toes. Lacking individual names, the metatarsal bones are numbered from the me ...

is straight. Its color is also as in ''A. Nahuelbuta''. *Female: total length ; cephalothorax length , width ; cephalic region length , width ;

fovea Fovea () (Latin for "pit"; plural foveae ) is a term in anatomy. It refers to a pit or depression in a structure. Human anatomy *Fovea centralis of the retina * Fovea buccalis or Dimple * Fovea of the femoral head * Trochlear fovea of the fr ...

width ; OQ length , width ; labium length , width ;

length , width . Its cephalic region is convex, with the fovea slightly procurved. Its labium possesses 1 cuspule. A well-developed serrula is present. Its sternal sigilla is small, shallow and marginal. Chelicerae: rastellum is absent. Color as in male.

Distribution

Only in its type locality.

References

External links

*
ADW entry
* {{Taxonbar, from=Q2112716 Pycnothelidae Spiders of South America Spiders described in 1995 Endemic fauna of Chile