Emmenomma oculatum Simon

Lina, Almeida-Silva, Charles, Griswold & Antonio, Brescovit, 2015, Revision of Emmenomma Simon (Amaurobiidae, Macrobuninae), Zootaxa 3931 (3), pp. 387-400 : 390-395

Emmenomma oculatum Simon

Figs. 1–7

Emmenomma oculatum Simon, 1884: 126 , pl. 3, figs. 8–11 (lectotype male, designated by Roth 1967: 318, paralectotypes 10♀, 3♂, 2imm, from Hoste and Hermite Islands, Orange Bay, Tierra del Fuego, deposited in MNHN 6687, examined); Simon, 1887: E19, pl. 2, fig. 8; Simon, 1898a: 247, figs. 231–232; Tullgren, 1901: 251, pl. 19, fig. 8; Roth, 1967: 317, pl. 51, figs. 12–13; Lehtinen, 1967: 443, figs. 179–180; Schiapelli & Gerschman, 1974: 88, figs. 39–42; Griswold et al., 2005: 9, fig. 183D; World Spider Catalog, 2014.

Emmenomma falklandicum Hogg, 1913: 45 , pl. 1, fig. 2 (holotype female, from Falkland Islands ( Malvinas), deposited in BMNH 1924.III.1.948, examined); Roth, 1967: 317 (Syn.); World Spider Catalog, 2014.

Emmenomma beauchenicum Usher, 1983: 557 , pl. 1, fig. 3 (holotype female, from Falkland Islands ( Malvinas), deposited in BMNH 1982.9.16.35, examined). Syn. nov.

Synonymy. Study of the type series of Emmenomma oculatum Simon, 1884 revealed that the few differences found in E. beauchenicum (lack of one spine on the retrolateral face of the metatarsus I, smaller size of the PME and PLE, darker coloration and larger size) and differences in the shape of the epigynum of E. oculatum and E. beauchenicum are only intra-specific variation and do not justify specific recognition. We conclude that Emmenomma beauchenicum from the Falkland Islands is a junior synonym of E. oculatum .

Notes. Since the specimens of Emmenomma oculatum used for the redescription are non-types deposited at the AMNH, in the “Additional material examined” section, they are tagged with an asterisk (*). The type series of Emmenomma oculatum was examined and they only contained a label by V. Roth designating the lectotype and paralectotypes. There was also another vial identified as “Mission du Cape Horn” from where the specimens were probably removed. This vial contains several specimens from all over the Orange bay and provided information on the intraspecific variation of E. oculatum .

Diagnosis. Females of Emmenomma oculatum differ from E. obscurum new rank and E. joshuabelli sp. nov. by the epigynum middle-field with two sclerotized plates ( Figs. 5 A–B; 6D); males of E. oculatum differ from E. joshuabelli sp. nov. by the sharp pointed TA in E. oculatum ( Figs. 3 A–D; 6B–C) rather than round TA in E. joshuabelli sp. nov. ( Fig. 9 C).

Description. Male (AMNH). Total length 7.20. Carapace piriform, length 3.00, width 2.38, height 0.95. Fovea long and deep. Anterior eye row slightly procurved, posterior recurved. Eye diameters and interdistances: AME 0.08; ALE 0.40; PME 0.14; PLE 0.23; AME–AME 0.10; AME–ALE 0.03; ALE–PLE 0.36; AME–PME 0.36; PME–PLE 0.25; PME–PME 0.14. Coloration: carapace brown with dark pigmentation parallel to fovea and covering muscular attachments; chelicerae, sternum, labium and endites brown; abdomen maculate, with cardiac area dark, guanine deposits laterally to cardiac area and chevron marks on the posterior dorsal area ( Fig. 1 B-C). Clypeus 0.11 high. Clypeal hood absent. Chelicerae geniculate, fang 0.65; paturon 1.10. Retromargin with three teeth and three denticles, promargin with four teeth. Labium 0.40 long, 0.46 wide, not rebordered, slightly notched at the apex. Leg measurements. I: femur 2.90/ patella 1.15/ tibia 3.10/ metatarsus 3.05/ tarsus 2.10/ total 12.30; II: 2.95/ 1.20/ 2.90/ 3.00/ 1.23/ 11.28; III 2.60/ 1.05/ 2.40/ 3.05/ 1.60/ 10.70; IV 3.10/ 1.10/ 3.15/ 4.00/ 1.95/ 13.30. Leg formula: 4123. Left legs and palp spination: femur: I: d 0-1-3; II: d 0-3-3; III: d 0-2(1r-1)-3; IV: d 0-2(1p-1)-3; palp: d 1-1; patella: I to IV and palp: d 1-0-1; tibia: I: v 2-2 -2, r 1-1-1, d 1-1, p 1-1-1; II: v 2-2 -2, r 1-2(1d-1)-1, d 0- 1, p 1-1; III and IV: v2-2 -2, r 1d-1d-1d, d 1-1, p 1d-1d-1d; metatarsus: I: v 2-2 - 1m, r 1-1-2, p 1-1-2; II: v 2-2 - 1m, r 0-0-2, d 1-1, p 0-0-2; III: v 2-2 - 1m, r 1-1-2(1- 1v), d 1-1-0, p 1-1-2(1- 1v); IV: v 2-2 - 1m, r 0-0-2(1- 1v), d 1-1-0, p 1- 1-2(1- 1v). Palp. Cymbium triangular, without apophysis ( Figs. 4 A; 6C), with a rounded and flat tarsal organ ( Fig. 2 C). E short, arising on prolateral side ( Fig. 4 F). MA bifid with a triangular basal lobe and a rectangular, distally curved apical lobe ( Figs. 3 B–D; 4D–F). TA small and pointed, near base of MA ( Figs. 3 B–D; 6B–C). DTP subrectangular and membranous ( Figs. 3 A, C, D). DTA composed of a mound from which an elbowed, retrolaterally displaced apophysis arises, that discharges the tibial gland content ( Figs. 3 C–D; 4A, B, D). RTA sharp pointed, mostly hidden by DTA ( Fig. 4 B). iRTA triangular in retrolateral view ( Figs. 4 B–C) and shallowly divided in ventral view ( Fig. 6 C). PTA small ( Fig. 4 A). VTA wide and thick ( Fig. 4 F). Spinnerets: ALS similar in size and shape to PLS ( Fig. 7 A). ALS with one MAP ( Fig. 7 B). PMS with at least four and PLS at least five AC spigots ( Figs. 7 C–D). Our images did not allow us to identify the mAP on the male PMS.

Female (AMNH). Total length 8.00. Carapace piriform, length 3.28, width 2.40, height 1.36. Fovea and eye rows as in male. Eye diameters and interdistances: AME 0.19; ALE 0.40; PME 0.20; PLE 0.23; AME–AME 0.11; AME–ALE 0.03; ALE–PLE 0.35; AME–PME 0.38; PME–PLE 0.32; PME–PME 0.16. Coloration as in male.

Clypeus 0.15 high. Clypeal hood absent. Chelicerae geniculate, fang 0.7; paturon 1.39. Retromargin with four denticles and three teeth ( Fig. 2 E). Labium 0.40 long, 0.50 wide, as in male. Leg measurements: I: femur 2.55/ patella 1.25/ tibia 2.60/ metatarsus 2.30/ tarsus 1.20/ total 9.90; II: 2.75/ 1.25/ 2.50/ 2.25/ 1.15/ 9.90; III 2.30/ 1.15/ 2.05/ 2.50/ 1.20/ 9.20; IV 2.55/ 1.20/ 2.85/ 3.40/ 1.60/ 11.60. Leg formula: 41=23. Left legs spination: femur: I to III: d 3-3; IV: d 2-3; palp: d 1-1; patella: I to IV and palp: d 1-1; tibia: I: v 2-2 -2, r 0-1, d 1-1, p 1-1-1; II and III: v 2-2 -2; r 1-1, d 1-1, p 1-1-1; IV: v 2-2 -2, d 1-1, p 1-1-1; palp: v 1-2 -1r; metatarsus: I and II: v 2-2 -1, r 1-1-1, p 1-1-1; III and IV: v 2-2 -1, d 1-1-2(1r-1p), p 1-1-1; tarsus: III and IV: v 1-2; palp: r 0-2-2-1, d 2-0. Palpal claw with 10 teeth ( Fig. 2 F). Endite serrula in a single row ( Fig. 2 D). Epigynum with triangular teeth ( Figs. 5 A–C). External wall of the CD separated by soft tissue, not forming a plate. CD straight ( Figs. 5 D–F) and S oval ( Figs. 5 D–F). BG present ( Fig. 5 D-F). Spinnerets: ALS with two MAP invaginated into the Pi field ( Fig. 7 F). PMS with two Cy ( Figs. 7 G–H) and four to eight AC spigots. PLS with two Cy and 12 AC spigots ( Fig. 7 I).

Variation. Length (10♂): Total: 5.75–7.20; Carapace: 2.75–3.00; Femur I: 2.65–2.90. Length (10♀): Total: 8.20–10.60; Carapace: 3.20–4.10; Femur I: 2.55–3.05.

Additional material examined. FALKLAND ISLANDS ( MALVINAS): Beauchêne Island (52º54'S 59º09'W), 7♀, 1♂, 4imm, R. L. Lewis-Smith coll. (NMH 1982.9.16.38; 1982.9.16.35; 1982.9.16.36; 1982.9.16.37; 1982.9.16.30; 1982.9.16.34; 1982.9.16.3; 1982.9.16.31; 1982.9.16.28; 1982.9.16.27; 1982.9.16.29; 1982.9.16.32); East Falkland, Mullet Valley (51°43'19"S 57°54'0"W) 3♀, 4–5.XII.1974, S. Coscarón, coll. ( AMNH). ARGENTINA: Tierra del Fuego, Carbajal Valley (54° 42' 00" S 68° 22' 00" W), 10♀, 3♂, 6imm, 17.II.1961, B.

Malkin coll. ( AMNH *); 13♀, 1 imm, same data ( AMNH); Ushuaia, Bahia Lapataia (54°51′19.57″S 68°34′22.07″W), 1♀, 20–23.II.1961, B. Malkin coll. ( AMNH); Isla de los Estados, 3♀, XII.1967, A. Backman coll.; Ushuaia (54°48′S 68°18′W), 19♀, 2♂, 3imm, B. Malkin, ( AMNH) CHILE: Magallanes & Antárctica Chilena: Tierra del Fuego: Bahía Inútil (53°21′S, 69°50′W), 2♀, 5–6.XI.1960, L. Peña ( MCZ); Camerón (53° 38′ 16″S 69° 38' 52″W), 1♀, 14–17.I.1960, L. Peña coll. ( MCZ); Rusfin, SE Camerón, 19♀, 1♂, 1imm, 17–21.XI.1960, L. Peña coll. ( MCZ); Rusfin, 92Km SE Porvenir, (53º44′48″S 69º13′22″W), elev. 237m 1♂, 16.XII.2009, H. Wood, L. Almeida-Silva and C. Griswold coll. (CASENT 9035244); Rusfin, near Vicuña, elev. 300m, 3♂, 6♀, 12 imm, 30.XI.1966, E. Schlinger & M. Irwin col. (CASENT 9020935); 1 imm same data (CASENT 9029034); Navarino Island, Puerto Williams (55° 4′ 31.8″ S, 67° 39′ 19.08″ W), 11♀, 3imm, XII/ 1962 – I/1963, P. J. Darlington coll. (MCZ—4 vials); Orange Bay, Cape Horn (55°30'51.01"S, 68° 5'13.90"W), 33♀, 3♂, 23 imm, 1882–1883; Dr. Hayes coll. ( MNHN).

Figures

FIGURE 1. Emmenomma oculatum. A – C: ♂ (recently molted); D: Immature. A. Carapace frontal view; B. Habitus, dorsal view; C. Habitus ventral view; D. Tapetum removed from ALE.

FIGURE 2. Emmenomma oculatum. A. Eyes, ♀; B. Eyes detail, AME and ALE, ♀; C. Tarsal organ, ♂ palp; D. Right endite, dorsal, ♀. E. Right chelicerae teeth, retromargin at top; F. Palpal tarsal claw, ♀.

FIGURE 3. Emmenomma oculatum right ♂ palp. A. Bulb, prolateral view; B. Median apophysis detail; C. Bulb, ventral view, including DTA tip (Arrow pointing to gland pore); D. Bulb, apical view, including DTA tip (Arrow pointing to gland pore). Abbrev.: DTP—distal tegular process; E—embolus; MA—median apophysis; TA—tegular apophysis; VTA—ventral tibial Apophysis.

FIGURE 4. Emmenomma oculatum ♂. A. Right palp dorsal view. B. Left palp, retrolateral view showing RTA and DTA. C. Left palp, retrolateral view, iRTA. D. Left palp, expanded, retrolateral view, bulb. E. Left palp, expanded, prolateral view, bulb. F. Left palp, expanded, ventro-prolateral view. Abbrev.: DTA—dorsal tibial apophysis; DTP—distal tegular process; E—embolus; iRTA—internal branch of the retrolateral tibial apophysis; MA—median apophysis; PTA—prolateral tibial apophysis; RTA—retrolateral tibial apophysis; TA—tegular apophysis TR—tegular rim; ST—subtegulum; VTA—ventral tibial apophysis.

FIGURE 5. Emmenomma oculatum ♀. A. Epigynum, ventral view. B. Epigynum, ventro-posterior view. C. Epigynum, posterior view; D. Vulva, left spermatheca. E. Vulva, dorsal view. F. Vulva, anterior view. Abbrev.: BG—Bennetts’s gland; CD—copulatory duct; LL—lateral lobe of the epigynum; MF—epigynum middle-field; S—spermathecae; ET- epigynum tooth; FD—fertilization duct.

FIGURE 6. Emmenomma oculatum. A – C: Left palp, ♂: A. Retrolateral view; B. Ventral view; C. Dorsal view. D – F: ♀ genitalia: D. Epigynum ventral view; E. Vulva dorsal view. Abbrev.: CD—copulatory ducts; DTA—dorsal tibial apophysis; DTP—distal tegular process; E—embolus; ET—epigynum tooth; FD—fertilization ducts; iRTA—internal branch of the RTA; MA—median apophysis; S—spermatheca.

FIGURE 7. Emmenomma oculatum, spinnerets. A – D. ♂. A. Overview. B. Left ALS; C. Left PMS; D. Right PLS. E – I. ♀. E. Spinnerets overview (colulus indicated by arrow). F. Left ALS. G. PMS overview; H. Right PMS. I. Right PLS. Abbrev.: AC—aciniform gland spigots; Cy—cylindrical gland spigot; MAP—major ampullate gland spigot; Pi—piriform gland spigot.

FIGURE 9. Emmenomma joshuabelli sp. nov. A – C. ♂, left palp: A. Retrolateral view; B. Dorsal view; C. Ventral view; D – F. ♀ genitalia: D. Epigynum ventral view; E. Vulva dorsal view. F. Epigynum posterior view. Abbrev.: CD—copulatory ducts; DTA—dorsal tibial apophysis; DTP—distal tegular process; E—embolus; ET—epigynum teeth; FD—fertilization ducts; iRTA—internal branch of the retrolateral tibial apophysis; LL—lateral lobes; MA—median apophysis; MF—epigynum middle-field; PTA—prolateral tibial apophysis; RTA—retrolateral tibial apophysis; S—spermathecae; ST—subtegulum; TA—tegular apophysis TR—tegular rim; VTA—ventral tibial apophysis.