Difference between revisions of "Eriauchenius milloti"

Latest revision as of 14:26, 8 January 2018

Taxonavigation

Ordo: Araneae
Familia: Archaeidae
Genus: Eriauchenius

Name

Eriauchenius milloti Wood & Scharff, 2017 sp. n. – Wikispecies link – ZooBank link – Pensoft Profile

Type material

Male holotype: MADAGASCAR, Toliara, Parc National Andohahela, Parcelle I, Manangotry, off Rte. 118, 34 km N Taolagnaro, 24°44'35.0"S, 46°51'23.3"E, 670 m, 23 Dec 2008 – 3 Jan 2009, primary montane rainforest, general collecting day and night, turning over dead palm frond bases on the ground, F. Alvarez-Padilla & H. Wood (deposited in USNM: USNMENT01377187).

Other material examined

Female paratype, 1 eggcase, same data as holotype (USNMENT01377188); 3M,11F,1 eggcase, same as previous (USNMENT01377189, USNMENT01377180, USNMENT01377181, USNMENT01377182, USNMENT01377183, USNMENT01377179, USNMENT01377171, USNMENT01377172); 2M3F, same as previous except turning over dead palm frond bases on the ground, F. Alvarez-Padilla & H. Wood (USNMENT01377176, USNMENT01377177); 1Juv, same as previous except general collecting day and night, beating vegetation (USNMENT01377178); 1M, Toliara, Foret Classee Tsikongambarika I, Ivolo forest, Andily, ca. Fort Dauphin, 24°56'13.5"S, 46°55'58.4"E, 20 m, 13 Mar 2003, rainforest, Ludd tree trunks/litter, D. Andriamalala, D. Silva et al. (CASENT9015862); 1Juv, Toliara, Foret Classee Tsitongambarika, Cascade trail hike, 7.5 km NW Taolagnaro, 24°59'11.9"S, 46°55'34.7"E, 100 m, 24 Dec 2008, primary montane rainforest, general collecting day and night, F. Alvarez-Padilla & H. Wood (USNMENT01377184); 1Juv, Toliara, Parc National Andohahela, Parcelle I, Manangotry, off Rte. 118, 32 km N Taolagnaro, 24°45'50.1"S, 46°51'23.5"E, 100 m, 25 Dec 2008, rainforest near stream surrounded by disturbed slash/burn forest, sifting and mini-winkler extraction of leaf litter, F. Alvarez-Padilla & H. Wood (USNMENT01377175).

Etymology

The specific name is a patronym to honor Dr. Jacques Millot for his work describing Madagascan archaeids.

Diagnosis

Males distinguished from other “bourgini group” species except E. pauliani and E. lukemacaulayi sp. n. (and presumably E. milajaneae sp. n., although the males are unknown) by the presence of a lateral process on the conductor, which is narrow in E. lukemacaulayi sp. n. and E. milloti (Figs 14E, G–I, 17D–I, asterisk), but is broader in E. pauliani (Fig. 18C–D, F–H, asterisk). E. milloti sp. n. is distinguished from E. lukemacaulayi sp. n. by the quarter-moon-shape of the pedipalpal bulbs (Fig. 17D–F, J–L). Females of E. lukemacaulayi sp. n., E. milajaneae sp. n., and E. milloti sp. n. (and presumably E. pauliani) are distinguished from other “bourgini group” females by the enlarged, extended U-shaped PB (Figs 14B, 16B, 17B). The PB is smaller and thiner in other “bourgini group” females. In E. milloti sp. n. the curved ends of the PB extend all the way to the anterior edge of the FSGP (Fig. 17B), whereas in E. milajaneae sp. n. and E. lukemacaulayi sp. n. the curved ends do not go past the anterior of the “wings” (Figs 14B, 16B).

Description

Male holotype (USNMENT01377187, from Parc National Andohahela, Madagascar). Total length 2.18, carapace 0.91 long, 0.85 wide. Abdomen 1.23 long, 1.31 high. Carapace tilt angle 69.58°, tilt height (CtH) 1.89, constriction 0.47, head length 0.81, neck length 0.92. CtH divided by carapace length 2.08. Cephalon with AME on large bulge. Cephalon with 4 short post-ocular spines at the crown, not on protrusions. Chelicerae 1.81 long, and with short spine 0.30 from base of chelicerae and projecting downward (Fig. 17A). Femur I 2.53 long. Sternum 0.59 long, 0.38 wide. Carapace, chelicerae, and sternum reddish brown with white setae, although chelicerae lighter brown in middle. All legs with parts that are lighter brown and parts with darker annulations. Abdomen yellowish white, with scattered small and large dark brown areas with yellowish spots, and with tufts of white setae (Fig. 17A). Pedipalpal bulb with a membranous sac above the base of the embolus, with a greatly exposed broad and dark embolus that is encircled by the conductor (Fig. 17D–L). Conductor with a small narrow process (Fig. 17D–I, asterisk) followed by a constriction (Fig. 17H, arrow) that is then followed by a large bulge on the retrolateral side.
Female paratype (USNMENT01377188). Total length 2.33, carapace 0.97 long, 0.88 wide. Abdomen 1.33 long, 1.51 high. Carapace tilt angle 62.94°, tilt height (CtH) 1.99, constriction 0.48, head length 0.87, neck length 0.95. CtH divided by carapace length 2.05. Cephalon as in male. Chelicerae 1.89 long, and with short spine 0.33 from base of chelicerae and projecting downward. Femur I 2.48 long. Sternum 0.64 long, 0.41 wide. Colors as in male, although abdomen with a greater degree of dark brown. Female genitalia FSGP with a rounded posterior elongation (Fig. 17B); PB large and U-shaped, extending to the anterior edge of the FSGP (Fig. 17B); poreplates in one group on each lateral side of the bursa anterior (Fig. 17C).

Variation

Total length 1.78–1.89 (males; n=5), 1.94–1.99 (females; n=5); Carapace length 0.88–0.91 (males; n=5), 0.94–0.99 (females; n=5); Femur I 2.73–2.82 times the length of carapace in males (n=5), 2.55–2.64 in females (n=5); CtH divided by carapace length 1.98–2.08 in males (n=5), 1.99–2.08 in females (n=5). Average femur I length 2.49 in both males (n=5) and females (n= 5).

Natural history

In primary rainforest from 20–640 m in elevation. Collected day and night, turning over dead palm frond bases on the ground, in litter, and on tree trunks.

Distribution

Known only from Parc National Andohahela and surroundings in the southeastern part of Madagascar (Fig. 32).

Original Description

• Wood, H; Scharff, N; 2017: A review of the Madagascan pelican spiders of the genera Eriauchenius O. Pickard-Cambridge, 1881 and Madagascarchaea gen. n. (Araneae, Archaeidae) ZooKeys, (727): 1-96. doi

Images

Figure 14. Eriauchenius lukemacaulayi sp. n. A female (USNMENT01377191) habitus, lateral view, image reversed B–C, F female internal genitalia (USNMENT01377192) B posterior view C anterior view F dorsal view, arrow showing the rounded posterior elongation on the FSGP that curves dorsally. D–E, G–I male pedipalpal bulbs (holotype, USNMENT01377191), right bulb, image reversed D, G prolateral view E, I retrolateral view H ventral view, arrow showing the large bulge that occurs after the constriction in the conductor. Asterisk (*) showing the narrow, lateral process on the conductor. Scale bars: 1 mm (A); 0.25 mm (B); 0.5 mm (D).  Figure 16. Eriauchenius milajaneae sp. n. A female (holotype, CASENT9009881) habitus, lateral view B–C female (holotype, CASENT9009881) internal genitalia: B dorsal view, arrow showing broad, rectangular, posterior elongation on the FSGP C anterior view. Scale bars: 1 mm (A); 0.25 mm (B).  Figure 17. Eriauchenius milloti sp. n. A male (USNMENT01377189) habitus, lateral view B–C female (USNMENT01377189) internal genitalia B dorsal view C anterior view D–I male pedipalpal bulbs D–F right bulb, image reversed, (USNMENT01377189) G–I left bulb (USNMENT01377189) J–K left bulb (CASENT9015862) D, G, J prolateral view E, H, K ventral view F, I, L retrolateral view. Asterisk (*) showing the narrow, small process on the conductor. Arrow showing constriction in the conductor. Scale bars: 1 mm (A); 0.25 mm (B, D).  Figure 18. Eriauchenius pauliani (Legendre, 1970), holotype, MNHN. A–B male A habitus, lateral view, image reversed B anterior view C–H male left pedipalpal bulb C, F prolateral view D, G ventral view, arrow showing the broken tip of the embolus in the left pedipalp E, H retrolateral view I male right pedipalpal bulb, embolus tip close-up showing the unbroken embolus, image reversed. Scale bars: 1 mm (A); 0.25 mm (C).  Figure 32. Distribution map for Eriauchenius species. ** The distribution for E. pauliani is an approximation as the holotype does not have latitude/longitude data.