Pholcus edentatus, CAMPOS & WUNDERLICH, 1995

Dimitrov, Dimitar & Ribera, Carles, 2007, The genus Pholcus (Araneae, Pholcidae) in the Canary Islands, Zoological Journal of the Linnean Society 151 (1), pp. 59-114 : 94-103

PHOLCUS EDENTATUS CAMPOS & WUNDERLICH, 1995

( FIGS 230–250 )

Pholcus edentatus Campos & Wunderlich, 1995: 295 , figs 4–9.

Material examined: 2 mm, 2 ff, from Barracno de Guayadeque , Gran Canaria, Canary Islands, Spain, 12.viii.2002, De Mas & Delgado ( CCRUB 4614-173 , 4594-172 , 4593-172 ) .

Diagnosis. P. edentatus can be distinguished from similar congeners by the following characteristics: the shape of the uncus, which has an inflection to its dorsal side ( Fig. 231 ); the shape of the procursus’ apical apophysis, which is lamellar with a wide base and irregular margins ( Fig. 245 ); the procursus’ large, heavily sclerotized dorsal apophysis ( Figs 230 , 243 ). The shape of the appendix of the bulb and the general morphology of the procursus are also very useful for identification purposes. The female is distinguished by a low triangular plate with a very wide base ( Fig. 235 ) as well as by the morphology of the vulva ( Fig. 237 ).

Description: Male: prosoma yellowish with brownish tones. Dorsally, a brownish colouring appears across the thorax. Ocular area elevated with brownish pigmentation around the eyes. Distance between AME and ALE equal to the diameter of ALE. Diameter of ALE half the diameter of ALE. Distance between AME strongly reduced. Frontal part of ocular elevation marked by darker pigmentation. Sternum yellow-brownish with darker margins. Chelicerae ( Figs 236 , 238, 239 ) slightly darker than the prosoma. The distal cheliceral apophyses dark brown, with bristles very close to their bases, and carrying two modified hairs ( Fig. 242 ) as well as a small dorsal protuberance. The apex of the proximolateral apophyses does not extend to the base of frontal prominences. Frontal prominences with darker outgrowths. Palp as in Figures 230, 231, 233 . Procursus ( Figs 230, 233 , 243, 244, 246 ) features large and heavily sclerotized dorsal apophysis. Apical apophysis of the procursus very wide, with one larger ventral part as well as numerous small apical outgrowths ( Fig. 245 ), and one smaller dorsal outgrowth. Tarsal organ as in Figure 250 . Opisthosoma yellow-brownish with cylindrical shape. Dorsally, eight darker spots appear distributed in two parallel longitudinal lines, their size decreasing towards the end of the opisthosoma. Ventrally, opisthosoma lighter with a darker transversal band over the genital area. Gonopore as in Figure 240 . Spinnerets as in Figures 247–249 .

Female: prosoma as in male except for the less pronounced elevation of the ocular area. Eyes closer together, with the distance between AME and ALE half the diameter of ALE. Sternum as in male. Chelicerae without apophyses. Colouring of opisthosoma as in the male. Epigynum and vulva as in Figures 232, 234, 235, 237 .

Measurements: Male: Prosoma 1.5 long, 1.9 wide. Opisthosoma 4.9 long, 1.9 wide. Total body length 6.4. Leg I femur 12.5, patella 0.7, tibia 13.2, metatarsus 22.0, tarsus 2.3, total 50.7. Palp femur 0.7, patella 0.3, tibia 0.8, procursus 0.8. Female: Prosoma 1.4 long, 1.5 wide. Opisthosoma 4.8 long, 2.4 wide. Total body length 6.2. Leg I femur 11.2, patella 0.8, tibia 11.7, metatarsus 18.0, tarsus 2.4, total 44.2.

Distribution: This species is endemic to Gran Canaria where it is known to inhabit Barranco del Guayadeque ( Fig. 276 ).

Natural history: P. edentatus lives in natural cavities in the lower parts of the Barranco de Guayadeque gorge. Although the walls of the gorge are very dry and with scarce xerophytic vegetation, the lower part is much more humid due to the development of limited agricultural activities and the accumulation of rain water.

Comments. All type material deposited in ULL is lost; however, the drawings provided in the original description by Campos & Wunderlich (1995) are sufficient to establish these specimens as conspecific with the lost types.

PHOLCUS FUERTEVENTURENSIS WUNDERLICH, 1992

( FIGS 251–268 )

Pholcus fuerteventurensis Wunderlich, 1992: 319 , figs 145–155; Campos & Wunderlich, 1995: 295, fig. 10.

Material examined: 1 m, holotype, from Barranco de Los Molinos , Fuerteventura, Canary Islands, Spain ( SMF 37189) ; 1 m, 5 ff, 1 juv., from Barranco de La Torre , Fuerteventura, 30.i.2003, Dimitrov & De Mas ( CCRUB 4658-173 , 4635-173 , 4633-173 , 4620-173 , 4523-170 ) ; 3 mm, 8 ff, 1 juv., from Barranco de Los Molinos , Fuerteventura, 29.i.2003, Dimitrov & De Mas ( CCRUB 4666-173 , 4634-173 , 4574-172 , 4522-170 , 4521-170 ) ; 2 mm, 2 juv., from Antigua, Fuerteventura , 29.i.2003, Dimitrov & De Mas ( CCRUB 4577-172 , 4668-173 , 4637-173 ) ; 1 m, 1 f, 1 juv., from Ajui , Fuerteventura, 29.i.2003, Dimitrov & De Mas ( CCRUB 4667-173 , 4573-172 ) ; 1 m, Pajara , Fuerteventura, 21.i.2003, Dimitrov & De Mas ( CCRUB 4575-172 ) ; 1 m, from Valle de Tarajala , Fuereteventura, 31.i.2003, Dimitrov & De Mas ( CCRUB 4576-172 ) .

Diagnosis: P. fuerteventurensis is distinguished from its similar congeners ( P. edentatus and P. anachoreta ) by the following characteristics: a pointed and unarched uncus with a less pronounced ridge ( Figs 252 , 261 ); the procursus’ smaller, sharpened, apical apophysis and the shape of its apical part ( Figs 251 , 267, 265 ); and the shapes of the appendix of the bulb ( Fig. 252 ) and the cheliceral apophyses ( Figs 256 , 258 ), which can also be used to identify this species. The female has a small triangular plate with two dark-coloured bands ( Fig. 255 ).

Description: Male: prosoma rounded with brownishyellow colour. Dorsally, the thorax with brownish colouring, which begins as two darker lines over the dorsal side of the ocular elevation and spreads almost completely across the thorax. Well-marked fovea yellowish in colour. Ocular area elevated with two lateral triads on short cylindrical outgrowths. Diameter of AME less than half the diameter of ALE. Distance between AME and ALE less than ALE diameter. Eyes surrounded by brownish pigmentation. Sternum yellowish with darker margins. Chelicerae ( Figs 256 , 258, 259 ) light brownish featuring dark distal cheliceral apophyses with two modified hairs and a conical outgrowth at the tips ( Fig. 260 ). Three bristles placed very close to the base of each distal apophysis. Frontal prominences carry very short outgrowths. Upper margin of proximolateral apophyses extends to the bases of frontal prominences. Palps as in Figures 251–253 . Procursus ( Figs 262, 265, 266 ) with two short dorsal spines ( Fig. 268 ). Apical apophysis of the procursus with wide base and sharpened apex ( Fig. 267 ). Distally, procursus carries one well-developed and strongly chitinized dorsal apophysis ( Figs 251 , 265 ). Opisthosoma cylindrical with brownish-yellow colouring. Dorsally, ten brownish spots are visible, arranged in two parallel longitudinal lines. The last spot in each line smaller and closer to the centre of the opisthosoma. Ventrally, a darker transversal band is visible over the genital area. Spinnerets as in Figures 263, 264 .

Female: the prosoma has the same colouring as in the male. Ocular area less elevated, with AME closer to the lateral triads. The brownish pigmentation around AME forms a continuous band, which extends over the frontal and dorsolateral parts of the ocular elevation. Sternum yellowish. Chelicerae as in male but without sexual modifications. Opisthosoma as in male but lighter. Epigynum and vulva as in Figures 254, 255, 257 .

Measurements: Male: Prosoma 1.3 long, 1.5 wide. Opisthosoma 3.7 long, 1.5 wide. Total body length 5.0. Leg I femur 9.0, patella 0.5, tibia 9.1, metatarsus 16.6, total 37.1. Palp, femur 0.7, patella 0.2, tibia 0.8, procursus 0.8. Female: Prosoma 1.1 long, 1.2 wide. Opisthosoma 3.7 long, 1.7 wide. Total body length 3.9. Leg I, femur 7.8, patella 0.5, tibia 7.6, metatarsus 11.7, tarsus 1.6, total 29.2.

Distribution: This species is known to inhabit many localities in Fuerteventura and also Barranco Hondo on Gran Canaria ( Fig. 276 ). Together with P. ornatus , this is the second species found on more than one island in the archipelago.

Natural history: P. fuerteventurensis is very widely spread all over Fuerteventura where it is found in cavities and small caves on hillsides. Some specimens were collected at sea-level in a small cave near Ajui, which is partially flooded during high tide. Although this species normally builds its webs on horizontal surfaces we observed webs built on practically vertical rocks in the Barranco de la Torre. Interestingly, P. fuerteventurensis has been found also in human constructions.

PHOLCUS BALDIOSENSIS WUNDERLICH, 1992

( FIGS 269–271 )

Pholcus baldiosensis Wunderlich, 1992: 318 , figs 141– 144a.

Material examined: 1 f, holotype and 1 juv., from Cueva de los Baldios , Tenerife , Canary Islands, Spain, 3.xi.1988, Oromí (in ULL); 1 f, from Cueva de La Puerta , Tenerife, 8.v.1993, Izquierdo ( CCRUB 4564- 171 ) .

Diagnosis: P. baldiosensis is easily distinguished from the rest of the epigean Canarian Pholcus species by such troglomorphic characteristics as the reduction in eyes and the very pale colouring. The most similar species, which also presents troglomorphies, is P. corniger . However, while in P. baldiosensis only AME and ALE are reduced, in P. corniger the eyes are completely lost. The epigynum and vulva’s morphology are also very characteristic ( Figs 269–271 ). The male P. baldiosensis remains unknown.

Description: Female: prosoma whitish with yellowish tones. Dorsally, some vestiges of thoracic pigmentation are visible. Well-marked fovea and cephalothoracic junction. Low ocular area, with eyes strongly reduced in number and size. AME and ALE absent, with the remaining eyes on two short cylindrical outgrowths. Ocular area whitish and lacking the darker pigmentation around the eyes typical of the epigean members of this genus. Sternum with brownish margins. Chelicerae and legs slightly darker than prosoma. Opisthosoma cylindrical and coloured like the prosoma. Ventrally, epigynum elevated with brownish triangular plate. Epigynum as in Figures 269, 270 . Vulva as in Figure 271 . Spinnerets with brownish spots.

Measurements: Female: Prosoma 1.0 long, 1.1 wide. Opisthosoma 2.2 long, 1.5 wide. Total body length 3.2. Leg I femur 7.3, patella 0.5, tibia 7.6, metatarsus 11.4, tarsus 1.9, total 28.7.

Distribution: This species is only known to inhabit the Cueva de los Baldios cave and Cueva de la Puerta on Tenerife Island ( Fig. 276 ).

Natural history: P. baldiosensis is a troglobite spider found in Cueva de los Baldios and Cueva de la Puerta away from the cave entrance. It builds its web close to the cave floor under stones or under protruding parts of the cave walls.

Comments: This was the first cave-dwelling species of Pholcus found in the Canary Islands. Unfortunately, the male of this species remains unknown.

Figures

Figure 276. Known distribution of Pholcus species endemic to the Canary archipelago.

Figures 230–237. Pholcus edentatus: 230, male palp, prolateral; 231, male palp, retrolateral; 232, pore plates of the vulva, dorsal view; 233, male palp, frontal; 234, epigynum, lateral; 235, epigynum, ventral; 236, male chelicerae, frontal; 237, vulva, dorsal. Scale bars 0.2 mm.

Figures 238–250. Pholcus edentatus: 238, male chelicerae, frontal; 239, male chelicerae, lateral; 240, male gonopore, ventral; 241, projections of the bulb, retrolateral; 242, distal apophysis of male chelicerae; 243, procursus, prolateral; 244, apex of procursus, frontal; 245, apical apophysis of the procursus, ventral; 246, procursus, retrolateral; 247, anterior lateral spinnerets; 248, spinnerets, ventral; 249, posterior lateral spinnerets; 250, male tarsal organ. Scale bars: 238, 239, 243, 244, 248, 200 µm; 240, 241, 245, 246, 100 µm; 247, 250, 50 µm; 242, 249, 20 µm.

Figures 251–257. Pholcus fuerteventurensis: 251, male palp, prolateral; 252, male palp, retrolateral; 253, male palp, frontal; 254, epigynum, lateral; 255, epigynum, ventral; 256, male chelicerae, frontal; 257, vulva, dorsal. Scale bars 0.2 mm.

Figures 258–268. Pholcus fuerteventurensis: 258, male chelicerae, frontal; 259, male chelicerae, lateral; 260, distal apophysis of male chelicerae; 261, projections of the bulb; 262, procursus, ventral; 263, anterior lateral spinnerets; 264, posterior median spinnerets; 265, procursus, prolateral (Dimitrov & Ribera, 2005a); 266, procursus, dorsal; 267, apical apophysis of the procursus, ventral; 268, small teeth on the procursus, dorsal. Scale bars: 258, 262, 265, 200 µm; 259, 261, 266, 267, 100 µm; 260, 263, 268, 50 µm; 264, 10 µm.

Figures 269–271. Pholcus baldiosensis: 269, epigynum, ventral; 270, epigynum, lateral; 271, vulva, dorsal. Scale bars 0.2 mm.