Physocyclus, SIMON, 1893

HUBER, BERNHARD A., 2000, New World Pholcid Spiders (Araneae: Pholcidae): A Revision At Generic Level, Bulletin of the American Museum of Natural History 2000 (254), pp. 1-348 : 148-150

PHYSOCYCLUS SIMON, 1893

Physocyclus Simon, 1893b: 470 (type species by original designation Pholcus globosus Taczanowski, 1874 ; examined). Gertsch, 1971: 61 62. Brignoli, 1981: 92 97. Huber, 1997b: 598; 1998d: 46 47.

I have not extensively studied representatives of this genus, but several points worth noting have emerged during the course of this study.

First, most (or all?) Physocyclus species share an easily visible apomorphy on the male procursus: a dorsal apophysis and a ventral pocket (a and p in fig. 577). These characters have been illustrated in some species (most clearly in P. bicornis by Gertsch, 1971, fig. 67), but often went unnoticed because structures and background are usually entirely black. I have checked some species in which the published illustrations suggested the absence of one or both characters ( P. cornutus Banks , californicus Chamberlin and Gertsch, enaulus Crosby, merus Gertsch, modestus Gertsch, pedregosus Gertsch, reddelli Gertsch, tanneri Chamberlin, validus Gertsch), but found them in all cases. The two characters form a functional unit, as the apophysis of one procursus is inserted into the pocket of the other procursus during copulation (studied in Physocyclus globosus by Huber and Eberhard, 1997). This character is apparently shared by Artema , but only behavioral observations could provide convincing evidence as to the homology of the structures (asymmetrical insertion of the procursi during copulation would strongly support the existence of an identical mechanism). Another character shared by Physocyclus and Artema is the brush on the procursus (e.g., figs. 48 49). The cones on the chelicerae, however, that seem so similar under the dissecting scope, are of a completely different nature: they are hairs in Artema (figs. 12 13), but sclerotized projections in Physocyclus (e.g., fig. 36). The relationship between the two genera remains unclear.

Second, as previously suggested (Huber, 1997b), Priscula is a well-defined genus, and is therefore removed from its synonymy with Physocyclus (synonymized by Brignoli, 1981). Hypsorinus (also synonymized with Physocyclus by Brignoli, 1981) is a synonym of Priscula . The cladistic analysis suggests that Priscula is indeed close to Physocyclus . However, considering the unclear position of Artema , the several differences between Physocyclus and Priscula , and their strict geographic separation, it seems preferable and more informative to keep the two genera apart.

Third, with the exception of the type species, Physocyclus seems to have a much narrower distribution than previously thought. At this point, only 3 of the previously 11 South American Physocyclus have not yet been transferred or synonymized: (1) P. dubius Mello-Leitao, 1922 (from Brazil), whose type material is apparently lost, but the original description strongly suggests that this is a synonym of P. globosus . Brignoli (1981) already suspected this synonymy, but did not formally synonymize the two names. The female has the typical petite élévation conique juste en arrière de la strie thoracique, and Mello-Leitao s description and illustration of the epigynum (1922: fig. 2) perfectly fits P. globosus . Therefore, the two names are herein synonymized (NEW SYNON- YMY). (2) P. viridis Mello-Leitao, 1940 ( Brazil) , in which the male has one pair of frontal apophyses on the chelicerae (Mello-Leitao, 1940c), in contrast to the several cones in

real Physocyclus . The type material is apparently lost, but the species is almost certainly misplaced. (3) P. tigrinus (Taczanowski, 1874) ( French Guiana), which Simon (1893b) thought was probablement a Priscula , and which then accidentally became a Physocyclus when Brignoli (1981) synonymized the two genera. I suspect it to be a synonym of Smeringopus pallidus (see Composition under Priscula description, p. 129). In conclusion, Physocyclus is probably not an original element of the South American fauna.

Most described Physocyclus species occur in western USA and Mexico (W. Gertsch in an unpublished manuscript prepared descriptions of 22 new species from this region). The southernmost reliable records (except P. globosus ) are of P. dugesi Simon and P. guanacaste Huber from Costa Rica, but even these species might be introduced there by humans. With the exception of P. globosus , Physocyclus seems to be absent from the Antilles. I strongly susupect that the recently described Chinese species P. orientalis Zhu and Song, 1999 (in Song et al., 1999) is a synonym of P. globosus .

For several reasons I have chosen P. mysticus rather than the type species for redescription as an exemplary species herein: (1) The type species P. globosus has been illus- trated several times in sufficient quality (e.g., Brignoli, 1981; Huber and Eberhard, 1997), and is one of the exemplar taxa in the cladistic analysis anyway; (2) Brignoli (1981) assumed that P. mysticus was misplaced, and suggested a transfer to Psilochorus . Howev- er, the illustrations of procursus and chelicerae (figs. 577 578) clearly show the structures on the procursus that define the genus (together with Artema ?), and the typical armature on the male chelicerae; (3) The species has never been redescribed, and the female has never been described.

Physocyclus mysticus Chamberlin, 1924 Figures 570 580

Physocyclus mysticus Chamberlin, 1924: 632 633, figs. 70 71. Brignoli, 1981: 94 (transfer to Psilochorus suggested).

TYPE: Male holotype from Tortuga Island (27°26'N, 111°52'W), Gulf of California , Baja California Sur, Mexico ; June 22, 1921 (E. P. van Duzée), in CAS (examined) .

DIAGNOSIS: Distinguished from congeners by the long, slender palpal femur with ventral apophysis (fig. 574), by the shape of bulb and procursus (figs. 576 577), and by the long epigynum with three small humps anteriorly (fig. 579).

MALE (holotype): Total length ~ 5.5 (opisthosoma shrunken), carapace width 2.8, length 2.8; leg 1 missing, tibia 2: 11.2, tibia 3: 8.3, tibia 4: 10.9. Habitus and prosoma shape as in figs. 570 572; thoracic groove slightly widened frontally, but not forming a pit; distance PME-ALE about 70% of PME diameter. Carapace ochre with brown median mark, ocular area with dark median stripe, clypeus with broad brown median band, sternum ochre-yellow, speckled with brown; chelicerae ochre with black cones frontally and stridulatory files laterally (fig. 578; pick is a modified hair proximally on palpal femur), palps proximally ochre-yellow, distally brown to black; coxa without retrolateral apophysis, femur long and slender, with ventral apophysis, procursus relatively simple, with hood (pocket) and apophysis as typical for genus (fig. 577), bulb with slightly twist- ed apophysis and additional smaller protrusion provided with little pointed teeth (fig. 576). Legs light brown, with darker rings on femora (subdistally) and tibiae (subproximally and subdistally); without spines and vertical hairs, with curved hairs on tibiae (few, ventrally) and metatarsi (many); retrolateral trichobothrium of tibia 1 at 12%; pseudosegmentation of tarsi not visible. Opisthosoma ochre-gray with stripes of black spots, genital plate long, light brown.

VARIATION: Tibia 1/ 2 in other males: 11.5/ 9.1, 9.2/7.2, 10.3/?, 10.0/8.0; some specimens have many white spots on the opisthosoma.

FEMALE: Tibia 1 (N = 6) 7.1 10.0 (x¯ = 8.3). In general very similar to male. Epigynum very long, anterior part with three small humps, light brown, posterior part flat, with darker brown marks (fig. 579). Dorsal view as in fig. 580.

DISTRIBUTION: Widely distributed in Baja California, Mexico.

MATERIAL EXAMINED: MEXICO: Baja California Sur: Tortuga Island : type above ; 5 mi N San Ignacio (Mission) (~ 27°30'N, 112°51'W), Jan. 20, 1965 (V. Roth), 13 in AMNH. Baja California Norte: 10 mi E El Rosario (~ 30°02'N, 115°36'W), May 5, 1961 (W. J. Gertsch & V. Roth), 13 in AMNH ; 3 mi N Punta Prieta (~ 29°00'N, 114°15'W), Feb. 25, 1966 (V. Roth), 2♀ in AMNH ; Bahia de los Angeles (28°55'N, 113°32'W), in building, Jan. 15, 1965 (V. Roth), 13 in AMNH ; Isla Cedros (28°12'N, 115°15'W), May 25, 1945 (B. F. Osorio Tafall), 13 2♀ in AMNH ; San Francisquito Bay (28°26'N, 112°53'W), Oct. 5, 1921 (J. C. Chamberlin), 13 in AMNH. Unidentified and unspecified localities: San Jose, Meling Ranch, May 1 4, 1961 (W. J. Gertsch & V. Roth), 13 5♀ 1 juvenile in AMNH ; Bartola Bay , Mar. 12, 1953 (B. Firstman), 1♀ in AMNH ; S.Ca., June 22, 1968 (William

et al., 2 vials), 13 1♀ 2 juveniles in AMNH ; in Boojum Trunk, Baja, Jan. 11, 1976 (Ward), 13 in AMNH .

Figures

Figs. 570 574. Physocyclus mysticus Chamberlin, male. 570. Habitus, lateral view. 571 572. Prosoma, frontal and dorsal views. 573. Left palp, prolateral view. 574. Left palp, retrolateral view. Scale lines: 1.0 mm.