Acrographinotus calilegua, Acosta, 2024

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 : 556-559

Acrographinotus calilegua sp. nov.

urn:lsid:zoobank.org:act:8BC0AE55-15C0-4A70-B67E-A6EA8E8BF527

Figs. 5A–F , 6A–C

Acrographinotus [sp. from NW Argentina] Acosta & Maury 1998: 573; Acosta 2001: 58, 60; 2002b: 78; Acosta & Pérez-González 2023: 326.

Type series. ARGENTINA, Jujuy Province. HOlOtYpe ♂ ( CDA 000.912), 1 ♀ paRatYpe ( CDA 000.913), 1 ♀ paratype ( LEA 000.125): Calilegua National Park, ‘ Monolito’, 25 February 1997, L. Acosta, M. Acosta leg. — 1 ♂, 1 ♀ paRatYpes ( MACN-AR 45699 ), Calilegua NatiOnal PaRk , 20.7 km fROm the entRance Of the PaRk [ca. 23°41.021’S 64°54.022’W, ~ 1698 m a.s.l.], 23–24 September 1995, M. Ramírez, P. Goloboff, C. Szumik leg. — 1 ♀ paRatYpe ( MACN-AR 45703 ), Calilegua NatiOnal PaRk , 8 km W fROm Mesada de las COlmenas, ca. 23°41.155’S 64°54.032’W, ~ 1660 m a.s.l., September 1995, P. Goloboff, M. Ramírez leg. — 2 ♀ paRatYpes ( MACN-AR 45701 ), Calilegua National Park , ca. 23°37.549’S 64°56.091’W, 2100 m a.s.l., 23 December 1994, C. Grismado leg.

Type locality. Calilegua National Park , ‘ Monolito’ (23°40.867’S 64°54.088’W, ~ 1705 m a.s.l.), Jujuy Province, Argentina .

Additional material. ARGENTINA, Jujuy Province. 1 ♀ ( LEA 000.148), DuRaznillO,between San FRanciscO and Alto Calilegua (Depto. Valle Grande), ca. 23°37.459’S 64°55.362’W, 2400 m a.s.l., 21 March 1997, Guardaparques Nicolossi & Zalazar leg. Remarks: This female largely oversizes all remaining specimens (DS length 7.6 mm, Fig. 2 ), so it is assigned to A. calilegua sp. nov. only tentatively, until additional samples are available .

Etymology. The specific name is a noun in apposition, referring to the Calilegua National Park (Jujuy Province, Argentina), where most types were collected.

Description. Measurements and meristics. DS length: males 5.7–6.2 mm (n=2), females 6.2–6.7 mm (mean 6.4 mm, n=6). FeIV/DS ratio (males): 0.84–0.89 (n=2). Detailed measurements of the holotype male and a female paratype in Table 1 . Tarsal formula: males 6:7–8:7:7 (holotype with 6:7:7:7), females 6:7–9:7:7.

Coloration in ethanol 70%. General color light cinnamon, with chelicera, pedipalps, legs I–III and metatarsus IV lighter; faint reticulated pigment on carapace and appendages; leg IV (coxa to tibia), free tergites (including apophysis) and venter of male darker (towards a reddish hue).

Males: Dorsum. DS tYpe λ (lambda, cOda shORt, caRapace with subpaRallel sides; Fig. 5A ), unaRmed, gRanulatiOn very unconspicuous. Anterior margin of carapace smooth, frontal hump shallow. Ocular mound low, with a blunt small median apophysis ( Fig. 5F ). DS area I divided; areas I–IV entire, almost smooth, except for sparse, tiny granules in a row. Area V, lateral areas and free tergites with a row of small granules. FT-III with an inconspicuous row of scarce granules and a strong median apophysis, curved (holotype) or horizontal (paratype) in lateral view.

Venter. Posterior margin of stigmatic segment like a flat bell curve. Free sternites with a row of minute granules. VAP bears a small ‘shelf-like’ projection; typical apophyses are lacking but they are replaced by a pair of small ventral, subapically shifted tubercles ( Figs. 5B, D ).

Chelicerae. Subtly rugous, bulla unarmed.

Pedipalps. Feeble, tegument finely rugous; blunt ventral setigerous tubercles on trochanter and femur; no medial subapical spine on femur. Pedipalp spination: LAT: Ti i_[Ii•], Ta iiii or •iii – MED: Ti Iiii or IiIi, Ta IIi.

Legs I–III. Unarmed, finely granulous on all segments.

Leg IV. Coxa IV smooth, with a diagonal prolateral apophysis, short and blunt, and a minuscule retrolateral one, perceptible from ventral and mostly hidden between trochanter and stigmatic segment. Coxa-trochanter joint oblique in ventral view ( Fig. 5B ).

Trochanter IV wide, asymmetric-subtrapezoidal; armature modest: a blunt prodorsal tubercle near the apical border, opposite to the coxal apophysis, and a small conic tubercle on the retrodorsal apical edge.

FemuR IV shORteR than DS and gentlY aRched, it aRticulates diagOnallY sidewaYs (diveRging bY ⁓45° fROm bOdY axis; Figs. 5A–B ); it is simple, with longitudinal rows of granules or small tubercles and subdistal narrowing not evident; dorsal and retrodorsal rows of blunt tubercles or low apophyses, the retrodorsal ends in a small conic subapical apophysis, pointing upwards ( Figs. 5A, E ); pro- and retrolateral rows of small, sparse granules, the latter ends in a conic apical aphophysis pointing medially ( Fig. 5B ); pro- and retroventral rows incomplete, granules larger and more acute distally, they end in a small unciform apophysis each.

Patella IV gently granulous, with 1–2 small acute retroventral tubercles.

Tibia IV with rows of conic granules, progressively larger on the retroventral row to end as small acute apophyses.

Penis ( Figs. 6A–C ). Distal end higher than wide, hourglass shaped in dorsal view due to VP sides markedly concave; front border of VP incurvate. Basal macrosetae (A1–A3 + B) in a transversal row, shifted more basally than the truncus-glans joint. Stylus tip abruptly inflected; VPS has the ‘ibis head with crest’ look typical for the genus, curvature of ‘beak-like’ process mild, while ‘veins’ in the membranous expansion are extremely tenuous.

Females: DS tYpe α-K (alpha-keYhOle, cOda mOdeRatelY lOng with diveRging sides), unaRmed, with gRanulatiOn subtly more conspicuous than males. Ocular mound slightly higher than males. FT-III with a row of acute granules and a small median apophysis. Margin of VAP with a pair of flat tubercles, as vestiges of the ‘shelf’ of males. Coxa IV: small acute prolateral apophysis. FeIV slender, slightly curved at its base, then sub-straight, with rows of granules; retroapical apophysis very small, pointing backwards.

Comparisons and diagnosis. This species is the smallest, less robust and with the simplest morphology in the genus. FeIV of male is slightly arched and articulates decidedly sideways ( Fig. 5A ); it is shorter than DS ( Fig. 2 ), while the ‘subapical narrowing’, typical for many species in the genus (like e.g., A. niawpaq or A tariquiae sp. nov.) is hardly perceptible. In fact, most features present in other congeners (namely those species from the couple 5 onwards in the key above), including apophyses and rows of tubercles of FeIV, can be identified though much more attenuated. Like in A. niawpaq and A. tariquiae sp. nov., VAP in A. calilegua sp. nov. bears a shelf-like projection (quadrangular in ventral view), but it is not flanked by large conical apophyses; instead, these appear to be represented by conic tubercles shifted subdistally in the ‘shelf’ ( Fig. 5B ). These differences remain valid even when compared to smaller A. tariquiae males, which still displaY an α-tYpe lOOk in spite Of theiR Reduced size and weakeR aRmatuRe. MORe challenging is tO identifY β-males Of A. tariquiae , for which a suite of subtle details can be considered, as follows:

Regarding females, DS of A. calilegua sp. nov. looks slightly wider, with constriction 2 less marked and midbulge less differentiated than in A. tariquiae sp. nov..

Distribution and habitat. Acrographinotus calilegua sp. nov. was recorded from a few sites in and near the Calilegua National Park, Jujuy Province, Argentina, a renowned biodiversity hotspot in the Yungas ecoregion ( Fig. 7A ). This protected area is accessible by Provincial Route 83, which ascends on the east-faced slope across different vegetation altitudinal belts: a piedmont-montane transition (500–850 m a.s.l.), the montane rainforests (the belt with the highest precipitation, 850–1300 m a.s.l.), and a montane rainforests-montane forests transition (1300–1600 m a.s.l.). Beyond the National Park itself, the road further leads to cloud forests (1600–2400 m a.s.l.), which give way to high altitude grasslands above ( Politi & Rivera 2005; Malizia et al. 2012). The elevation range of A. calilegua sp. nov. (1660–2400 m a.s.l.) places this species in the upper forest belt (cloud forests: Fig. 7B ) and some transitional sites. In lower vegetation belts of Calilegua, especially in montane rainforests, samples are dominated by another gonyleptid, Pachyloides sicarius ( Roewer, 1925) (LEA unpubl. records).

Figures

FIGURE 2. Comparative morphometrics of Acrographinotus tariquiae sp. nov. and A. calilegua sp. nov., displayed as box-plots with data points (internal lines, dashed: mean, solid: median). Left: DS length (in mm) for males and females; the single outlying female from El Duraznillo (star), tentatively assigned to A. calilegua but not used in calculations, is shown for reference. Right: FeIV/DS ratio, males. In box-plots of male A. tariquiae, small aRROws fROm the left identifY the twO examined β-males.

FIGURE 5. Acrographinotus calilegua sp. nov., HOlOtYpe ♂ (CDA 000.912). A. DORsal scutum, fRee teRgites (alsO shOwing VAP process from above), coxae IV, right trochanter and femur IV, dorsal view. B. Venter, with coxae IV, genital and stigmatic segments, free sternites, ventral anal plate, right trochanter and femur IV. C. Right coxa, trochanter, femur, patella and tibia IV, prolateral view. D. Detail of free tergites, dorsal and ventral anal operculum, lateral view. E. Right femur and patella IV, retrolateral view. F. Ocular mound, posterior view. Scale lines: 2 mm (A–E), 1 mm (F).

FIGURE 6. Acrographinotus calilegua sp. nov., distal end Of penis. A–B. PaRatYpe ♂ (MACN-AR 45699): A: dORsal view; B: lateRal view (membRanOus cRest is bent); C. HOlOtYpe ♂ (CDA 000.912), detail Of stYlus and ventRal pROcess. Scale lines: 0.1 mm (A, B), 0.05 mm (C).

FIGURE 7. A: Records of Acrographinotus tariquiae sp. nov. in Tarija Department, Bolivia (yellow dots) and A. calilegua sp. nov. in Jujuy Province, Argentina (red dots); blue contours: protected areas (1: Tariquía Flora and Fauna National Reserve; 2: Calilegua National Park). B: Type locality of A. calilegua sp. nov.: cloud forests at ‘Monolito’ (ca. 1700 m a.s.l.), Calilegua National Park, Jujuy Province, Argentina.