Acrographinotus Holmgren, 1916, 1917

Acosta, Luis E., 2024, The two southernmost species of the Andean genus Acrographinotus Holmgren (Arachnida, Opiliones, Gonyleptidae) described from Bolivia and Argentina, Zootaxa 5481 (5), pp. 547-562 : 550

Acrographinotus Holmgren, 1916

urn:lsid:zoobank.org:act:41185CA6-EC2C-4040-A8FF-99158F984DA2

Acrographinotus Holmgren 1916: 89 ; Acosta 2001: 58 [complete synonymy].

Type species. Acrographinotus erectispina Roewer, 1929 , by subsequent designation of Roewer (1929) (see nomenclatural history in Acosta 2001).

Included species. Acrographinotus erectispina Roewer, 1929 , A. curvispina Roewer, 1929 , A. ortizi ( Roewer, 1957) , A. ornatus ( Roewer, 1929) , A. ceratopygus ( Soares & Bauab, 1972) , A. mitmaj Acosta, 2002a , A. niawpaq Acosta, 2001 , A. opacus ( Roewer, 1952) , A. tariquiae sp. nov., A. calilegua sp. nov.

Remarks. The most recent incorporation into the genus is A. opacus , originally described in the Brazilian genus Liogyndulus Mello-Leitão, 1932 . As Soares & Soares (1984: 309) synonymyzed the latter under Cobania Roewer, 1913 , the combination Cobania opaca was implied ( Acosta 1996), though never explicit. “ Liogyndulus” opacus was listed by Kury (2003: 153) as Pachylinae incertae sedis, because “this species has nothing to do with Cobania ”. Finally, Kury & Pinto-da-Rocha (2020) placed it in Acrographinotus , an action upheld by the diagnoses match (details not given, however) and biogeographic considerations (an Andean species is unlikely to belong to a Brazilian genus). Since the types and only known specimens of Liogyndulus opacus are two females and a juvenile ( Acosta 1996), while sound diagnostic features involve males ( Acosta 2001), this assignment should be taken with caution and would require further evidence.

Distribution. Higher altitudinal belts on Andean and sub-Andean ranges of Perú, Bolivia and northern Argentina ( Fig. 1 ); elevation range 1660–4750 m a.s.l. (~29% of records from above 4000 m; 77% above 3000 m; only 5% below 2000 m).

Diagnosis update. Ocular mound with a median apophysis, either tall or low, acute or blunt; in species with low armature (e.g., A. mitmaj , A. ortizi ), intraspecific variation may span from a short apophysis to completely unarmed, even with a median depression or notch instead, giving the false appearance of a paired condition. DS in most cases unarmed, be it smooth or with barely scattered granulation or very small round tubercles; only exceptionally ( A. ornatus ) tubercles are large in all areas, pustule-like (males) or round-flat (females). Pp femur without a medial subapical spine. Tarsal formula 6:8–10:7:7. Males with FT-III armed by a single median apophysis, sometimes with a row of granules or (seldom) small apophyses on each side. Free tergites I–II and dorsal anal plate unarmed. VAP either completely unarmed, just granulous, or armed with a pair of horn-like apophyses, be it independent or fused to a shelf-like tegumentary projection in between (in A. calilegua sp. nov. only the latter remains). Coxa IV with a short prolateral apophysis, blunt or truncate, mostly transverse or slightly diagonal; it is rarely large and sigmoid ( A. ornatus ). Trochanter IV sub-trapezoid, articulated obliquely outwards; it is most frequently asymmetric (the prolateral side shorter than the retrolateral one); exceptions are A. ornatus and A. mitmaj , with trochanter IV more symmetric in shape and articulation fairly straight. FeIV straight or arched, in most species with longitudinal rows of granules or blunt tubercles; in some cases ( A. curvispina , A. ortizi , A. mitmaj ) granules and apophysis are acute; only exceptionally spine-like apophyses are very large ( A. ornatus ). Penis: distal end of VPS dilated and armed with a downward-pointing process; on top of the dilated portion there is, with a few exceptions, a membranous projection (the VPS has been described to resemble a ‘round-crested ibis head’). Besides the armature of ocular mound, DS and FT-III, the feature, VPS shape is the best defining character of Acrographinotus among Pachylinae genera ( Acosta 2001).

Figures

FIGURE 1. An overview of the known records of genus Acrographinotus (red dots), spread between 5°55’S and 23°41’S along Andean and sub-Andean ranges of Perú, Bolivia and northwestern Argentina (ARG.). The blue arrow points the ‘Andean elbow’ at around 18°S. References for localities cited in the text: 1: Route Olmos-Jaén (presumed doubtful record); 2: Yánac; 3: Unduavi; 4: records in Tarija Department. Inset (left): location of the represented area in South America. Yellow square: area enlarged on Fig. 7A.