Ectatosticta davidi (Simon)

Platnick, Norman & Jaeger, Peter, 2009, A new species of the basal araneomorph spider genus Ectatosticta, ZooKeys 16 (16), pp. 209-215 : 210-212

Ectatosticta davidi (Simon)

Figs 1-4

Hypochilus davidi Simon, 1888 : ccviii (one male and one female syntypes, supposedly from mountains north of Beijing but probably from Inkiaphou, Shaanxi Province, China, in MNHN, examined).

Ectatosticta davidi: Simon 1892: 204 , figs. 143-146, 148-149. Gertsch 1958: 13, figs. 10, 19, 22-31. Lehtinen 1967: 298, fig. 15.

Diagnosis. Males of E. davidi can be distinguished from those of E. deltshevi by the details of the distal modifications on the retrolateral side of the palpal tibia. In E. davidi , there is a small triangular lobe followed apically by a large ledge bearing 5-7 thickened setae, all closely appressed ( Fig. 3 ); in E. deltshevi , there are only four thickened setae, and the most dorsal of those is smaller and well separated from the main group of three ( Forster et al. 1987: fig. 81). Females of E. davidi ( Fig. 4 ) have the inner pair of spermathecae relatively larger and more robust than is the case in E. deltshevi ( Forster et al. 1987: fig. 82).

Male. Total length 9.57. Carapace 4.61 long, 3.78 wide, yellow, with margins of pars cephalica and pair of broad marginal bands mottled with purplish brown, similar mottling along midline, with additional pair of purple lines originating anterior of thoracic groove, extending to posterior median eyes; clypeus at middle about twice AME diameter in height. Eye sizes and interdistances: AME 0.09, ALE 0.18, PME 0.21, PLE 0.15; AME-AME 0.15, AME-ALE 0.26, PME-PME 0.22, PME-PLE 0.15, ALE-PLE 0.06; MOQ length 0.37, front width 0.33, back width 0.63. Chelicerae yellow, unmarked; endites light brown, darkened distally; labium light brown, darkened distally; sternum light brown, with three broad, transverse bands of purple pigment covering most of surface. Legs light brown, with femora, patellae, and tibiae darkened distally. Femur I more than twice as long as carapace. Leg spination (only surfaces bearing spines listed): femora: I d3-0-0, p0-4-1, r1- 3-1; II d3-0-0, p0-3-2, r3-3-1; III d3-0-0, p1-2-1, r3-2-1; IV d4-0-0, p1-3-1, r0-2-2; tibiae: I d1-0-1, p2-2-1, v4-4-3, r2-3-1; II d1-0-1, p2-2-1, v4-4-3, r2-2-1; III d1-0-1, p1-2-1, v2-2-2, r1-2-1; IV d1-0-1, p1-2-1, v2-2-1, r1-2-1; metatarsi: I d1-0-0, p1-2-2, v2-4-4, r1-1-0; II, III d1-0-0, p1-1-0, v4-4-2, r1-1-0; IV p1-0-1, v2-2-0, r1-0-1. Dorsum of abdomen white with about six purple chevrons, posterior ones stronger than anterior ones, covering most of posterior one-third, sides and venter mottled except on lung covers. Retrolateral side of palpal tibia distally with small triangular lobe followed distally by large lobe bearing 5-7 modified setae, all closely appressed ( Fig. 3 ); embolus rounded, more smoothly curved than in E. deltshevi ( Figs 1-3 ).

Female. As in male, except as noted. Total length 10.98. Carapace 4.20 long, 2.97 wide. Eye sizes and interdistances: AME 0.11, ALE 0.20, PME 0.20, PLE 0.18, AME- AME 0.14, AME-ALE 0.25, PME-PME 0.30, PME-PLE 0.15, ALE-PLE 0.09; MOQ length 0.37, front width 0.36, back width 0.70. Chelicerae light brown; sternum with only one anterior transverse light band interrupting purple mottling. Femora darkened medially and distally, tibiae and metatarsi with basal, median, and distal darkenings. Leg spination (only surfaces bearing spines listed): femora: I d2-0-0, p1-2-3, r2-4-2; II d2-1-0, p1-1-2, r2-3-1; III d2-3-0, p1-1-1, r3-3-2; IV d3-1-0, p0-2-1, r0-1-2; tibiae: I d1-0-1, p2-1-1, v2-5-2, r1-2-1; II d1-0-1, p1-2-1, v4-5-2, r1-2-1; III d1-0-1, p1-2-1, v2-2-2, r1-1-1; IV d1-0-1, p1-1-0, v2-3-2, r1-1-0; metatarsi: I d1-0-0, p1-1-0, v2-4-4, r1-1-0; II d1-0-0, p1-1-0, v4-4-4, r1-1-0; III d1-0-0, p1-1-0, v4-2-2, r1-1-0; IV p0- 1-0, v1p-1p-1p, r0-1-0. Inner pair of spermathecae relatively long, robust throughout their length ( Fig. 4 ).

Material Examined. CHINA: Shaanxi: Inkiaphou ( AMNH), 1♀ ; presumably Inkiaphou , label reads only “ Sina ” ( MNHN 7285 ), 1♁, 1♀ (syntypes) ; Mt. Taibaishan, S flanks, above Houshenzi , 33°54’43.98”N, 107°46’44.06”E, June 12-15, 1997, tree line, scattered mixed coniferous/ Rhododendron forest, elev. 3050 m (P. Jäger, C. Fischer, AMNH), 1♁, 2♀, same ( IZCAS), 1♁, 1♀, same ( SMF), 1♁, 8♀ (not all dissected, some may be juvenile), June 25, 1997, primary broad-leaved forest, elev. 2500-2600 m (J. Martens, P. Jäger, SMF), 1♀ .

Natural History. According to observations by the second author at Mt. Taibaishan, E. davidi occurs in stony debris in open, semi-open, and forest-covered habitats. One part of the elongate sheet-web ( Fig. 5 ) is situated at the surface and connected to a stone or rock and surrounding vegetation. The apparently larger part of the web leads, as a narrow band, deep into the debris. Spiders cannot be seen or lured out of their retreat during the day. When it gets dark, the spiders sit close to the surface part of the web, ready to escape to their retreat. One male was found walking around, apparently searching for a female. Another male was observed during courtship, at the margin of a female’s surface web; that male touched the web only with its first pair of legs. The third male was taken in its own web.

Distribution. Known with certainty only from Shaanxi Province, China ( Fig. 6 ).

Figures

Figure 5. Web of Ectatosticta davidi (Simon) from Mt. Taibaishan, Shaanxi, China.

Figure 6. Map of China, showing records of Ectatosticta.

Figures 1-4. Ectatosticta davidi (Simon): 1 left male palp, prolateral view 2 same, ventral view 3 same, retrolateral view 4 female spermathecae, dorsal view.