Pseudocleobis solitarius : Maury 1976
Creators: name: Iuri, Hernán A.
name: Iglesias, Mónica S.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Solifugae
Ammotrechidae
Pseudocleobis
Pseudocleobis solitarius

description: Pseudocleobis solitarius Maury, 1976
(Figs. 2D–F; 5; 6D, E; 8C–E; 9F; 10F; 11D; 12J–L; 15. Table 1, table 2)
Pseudocleobis solitarius: Maury 1976: 87–94 –101, figs.: 24–25; Maury 1983: 172.
Type material (examined). Holotype: ARGENTINA: Río Negro: ♂, Paso Córdoba [39º06’47,46’’S 67º37’34,08’’W], General Roca, I.1961, A. Bachmann coll., (MACN-Ar 6886); Paratypes: ARGENTINA: Río Negro: 1♂, General Conesa [40º06’14,71’’S 64º27’30,59’’W], 16.II.1941, M. Birabén coll., (MACN-Ar 6887).
Other examined material: ARGENTINA: Mendoza: 3♂, 1♀, El Nihuil [35º01’40,53’’S 68º40’20,51’’W], 8.XI.1952, R. Cotta coll., (MACN-Ar 7589); Neuquén: 1♂, Arroyito [39º04’09,53’’S 68º33’54,11’’W], 7.I.1986. M. & P. Gentilé coll., (MACN-Ar); Río Negro: 1♂, San Antonio Oeste [40º43’48,82’’S 64º56’19,98’’W], 19.I.1994, A. Roig coll., (MACN-Ar); 7♂, 11♀, 1 immature, Paso Córdoba, near the Nautical Club “Julio A. Trulls” [39º06’46,16’’S 67º37’12,45’’W], 16–21.I.2015, H.A. Iuri coll., (MACN-Ar); 5♂, 2♀, same locality and collector, I-2016, (MACN-Ar); 5♂, 1♀, Valcheta, near the abandoned fluorite factory [40°39’58,87”S 66°10’13,84”W], 10– 12.I.2015, H.A. Iuri coll., (MACN-Ar); 3♂, Playas Doradas, “sendero del cuis” [41°38’46.55”S 65° 1’27.64”W], 8–10.I.2015, H.A. Iuri coll., (MACN-Ar).
Material tentatively assigned to P. solitarius: Argentina: San Juan: 1♂, Ichigualasto [30º09’49,70’’S 67º50’32,98’’W], 17.XII.1979, E.A. Maury & A. Roig coll., (MACN-Ar 7590); 1♂, Bermejo [31º35’21,68’’S 67º39’32,67’’W], 15.XII.1979, E.A. Maury & A. Roig coll., (MACN-Ar 7591).
Diagnosis: The flagellum attached at level between FSD and FM teeth (Fig. 8D), and the stylet-like fixed finger mucron on males (Figs. 8C; 12J) are characteristic for this species. Pseudocleobis solitarius resembles P. mustersi, in the shape on the flagellum-mucron complex. However, P. mustersi has other unique modifications on the chelicerae such as a bifurcated movable finger mucron. All the others Pseudocleobis examined have a wider shaped flagellum with an attachment ring at level between the FSM and FP teeth or posterior.
Note: The female of P. solitarius has a wide, bell-shaped genital plate with a large oval opening in the middle (Fig. 10F). This shape is different from all other described females of Pseudocleobis. However, as the female genital plate has been proved to be uninformative at the species level in some cases (see P. huinca, P. bardensis and P. profanus), and the females of some species from southern Patagonia are unknown (e.g., P. mustersi, P. levii) we prefer not mention it as diagnostic for the species.
Redescription: Male: measurements in Table 1. Color in vivo (Fig. 2E–F). Specimens of the population from the type locality possess a whitish body coloration pattern with beige legs.
Color in 96 % ethanol. The pattern in alcohol is quite similar to the live specimens, except that the body turns more whitish and legs turn darker.
Morphology and Chaetotaxy: General body chaetotaxy as described for P. profanus. Fixed finger (Figs. 8C–D; 12J): the fixed finger mucron is much narrower than the movable finger mucron (Fig. 8C, D). The FSD smaller than FD and FM, but generally well developed, not vestigial (Fig. 8D). The FSM and FM teeth are separated by a short diastema. Movable finger (Fig. 8C–D): the movable finger is robust and possesses a wide dorsal crest on the mucron. The three teeth (MM, MSM, MP) are widely separated from each other. Flagellum (Figs. 8D; 9F; 12J): the flagellum in very narrow (Fig. 9F) with small attachment ring placed at level between FSD and FM teeth (Fig. 8D). The flagellum reaches almost the tip of mucron (Figs. 8D; 12J). The central portion of the prolateral surface possesses some prominent filaments (Fig. 12J). The membrane, in general, is thicker than the flagellum of the other species treated here, and with some flat filaments in the retrolateral surface. The apex has some surface roughness and a few, very small, projections. Pedipalps (Fig. 15A–C): chaetotaxy as described for P. profanus sp. nov. except that the spiniform setae are more setiform (thin and undulate), more equally sized (especially those of the tibia), and the clubbed setae were not seen. Leg I (Fig. 15D–F): similar to P. profanus, but the clubbed setae (Fig. 15F) are less abundant. Opisthosoma: ctenidia: 5-5 on sternite III and 4-4 on sternite IV (Fig. 15J).
Female: Measurements in Table 1. Color in vivo: As in Fig. 2D. Morphology and chaetotaxy similar to male, except by wider propeltidium, wider chelicerae, and more robust body in general (Fig. 2D). Pigment pattern similar to males. The spiniform setae of the pedipalps are more spiniform than in males (especially those of the tibia). Genital plate (Fig. 10F): the genital plate is relative wide, bell-shaped. There is a large oval opening in the middle, covered distally by two whitish rigid plates. The lateral margins are straight or concave. Short, thick, bifurcated tip setae are placed on the lateral margins.
Variability: Dentition variability on both sexes is detailed in Table 2. A careful examination shows that the dark brown areas on propeltidium and chelicerae of P. huinca, are whitish in the specimens of P. solitarius from Paso Córdoba. That coloration allows to easily distinguishing it from P. huinca (found in sympatry in the type locality). However, specimens of P. solitarius, from other populations (i.e., Playas Doradas and Valcheta), possess some brown pigment similar to P. huinca (also found in sympatry on these localities), so they cannot be easily distinguished by the coloration in these areas.
Distribution: The records of P. solitarius are from the Austral and Septentrional districts of the Monte biogeographic province (Figs. 1A–B, D; 5). However, we found females of Pseudocleobis with the P. solitarius genital plate shape at the MACN collection, from the Chubut and Santa Cruz districts of the Patagonian biogeographic province. As we could not study males from these localities, these females are included in the distribution map as solitarius shape. The males recorded by Maury (1983) for San Juan province have some slight differences in the shape of cheliceral fingers mucra, and they could belong to a different species. However, due to the scarcity of material, we maintain these here as P. solitarius.
Examined material of Pseudocleobis sp. (females solitarius shape): ARGENTINA: Chubut: 1♀, 15 km S of Los Tamariscos, 19.I.1977, E.A. Maury and Petriccha coll., (MACN-Ar); 1♀, Puerto Lobos, 1.II.2016, E.A. Maury coll., (MACN-Ar); 1♀, Puerto Lobos, Arroyo Verde, 25–26.I.1975, E.A. Maury, C. Césari and P. Domínguez coll., (MACN-Ar); 1♀, Puerto Madryn, XII.1981, P. Goloboff coll., (MACN-Ar); 1♀, Telsen, XII.1981, P. Goloboff coll., (MACN-Ar); 1♀, Rada Tilly, near Punta del Marqués [45°57’8.33’’S 67°33’7.35’’W], 28–30.I.2015, H.A. Iuri coll., (MACN-Ar); Río Negro: 1♀, 5 km of Moligue, 1500 masl, 20.I.1973, (MACN-Ar); 1♀, Sierra Grande, near the cemetary [41º36’16.62’’S 65º23’12.77’’W], 19–20.I.2016, H.A. Iuri coll., (MACN-Ar).
description: Published as part of Iuri, Hernán A. & Iglesias, Mónica S., 2022, The genus Pseudocleobis Pocock, 1900 (Solifugae: Ammotrechidae) in transitional Patagonia-Monte deserts, with descriptions of two new species, pp. 435-460 in Zootaxa 5094 (3) on pages 452-457, DOI: 10.11646/zootaxa.5094.3.4, http://zenodo.org/record/5974250