Glenognatha timbira, Cabra-García & Brescovit, 2016

Jimmy Cabra-García & Antonio D. Brescovit, 2016, Revision and phylogenetic analysis of the orb-weaving spider genus Glenognatha Simon, 1887 (Araneae, Tetragnathidae), Zootaxa 4069 (1), pp. 1-183 : 144-148

Glenognatha timbira new species

( Figs. 118–121 , 135 )

Types. Male holotype from Parque Nacional da Serra dos Órgãos, Teresópolis, Rio de Janeiro, Brazil, [22º29´35´´S, 43º4´24´´W], elev. [1700m], 20–23.x.2006, Exped. Arachné leg., deposited in MNRJ 6399 ; paratypes: 3♂ 3♀ 2 immature with the same data of the holotype, deposited in MNRJ 6598 ; 1♂ from Túnel do Garrafão , Alagoa, Minas Gerais, Brazil, 22º11´S, 44º44´W, elev. [1340m], 31.ix.2008, L.F.O. Bernardi leg., deposited in UFMG 8790 .

Etymology. The species epithet is a noun in apposition that refers to the Timbiras indigenous tribes, first inhabitants of the type locality.

Diagnosis. Males of G. timbira resemble those of G. emertoni , G. minuta and G. gouldi by the enlarged Ret2 and Ret3 ( Figs. 119B–C ). It can be distinguished from G. emertoni by the absence of a mesally oriented distal projection on the cheliceral basal segment ( Fig. 119 A ); distinguished from G. minuta by the smaller size of the Ret3 relative to Ret2 ( Fig. 119B ) and from G. gouldi by the slightly curved Ret2 ( Fig. 119B ). Females can be distinguished from all other Glenognatha species by the enlarged base of the Prt1 ( Fig. 119D ).

Male (holotype). Habitus as in Figures 118 A –D . Carapace pale brown, darker along furrows. Sternum brown, darker on sides. Abdomen oval, dorsally with irregular pattern of two longitudinal black bands on sides that join medially at the posterior region forming thin transverse bands. Silver guanine spots scattered in two median longitudinal bands and on lateral surfaces. Venter with a pale black median band that ramifies towards the lateral surface from the tracheal spiracle. Silver guanine spots scattered in two lighter longitudinal bands between the tracheal spiracle and the epigastric furrow. Legs yellow-brownish. Tracheal spiracle well-sclerotized. Total length 3.75. Cephalothorax 1.75 long, 1.35 wide, 0.95 high. Abdomen 2.30 long, 1.80 wide, 1.80 high. Sternum 0.90 long, 0.90 wide. Eye diameters and interdistances: AME 0.12. ALE 0.10. PME 0.15. PLE 0.12. AME-AME 0.09, AME- ALE 0.12, PME-PME 0.15, PME-PLE 0.13, ALE-PLE 0.01. Clypeus height 1.80. Chelicerae with the same coloration of the cephalothorax and anteriorly projected ( Fig. 118C ). Three promarginal and four retromarginal teeth. ( Figs. 119 A –C ). Cheliceral fang curved ( Fig. 119C ). Leg measurements: I: femur 2.40, patella 0.65, tibia 2.50, metatarsus 2.20, tarsus 1.10, total 8.85; II: 2.40, 0.65, 2.45, 2.00, 1.00, 8.50; III: 1.60, 0.40, 1.25, 1.15, 0.57, 4.97; IV: 1.80, 0.45, 1.60, 1.40, 0.62, 5.87. DTS 0.32. DTE 0.70. Palp as in Figures 120E–H . Paracymbium with distal and basal portions subequal ( Fig. 120H ). Embolus long with a nearly 90º curved tip ( Figs. 120 A, D, G ).

Female (MNRJ 6400). Coloration and general habitus as in male ( Figs. 118E–H ). Abdomen with four dusky longitudinal bands. Pale patch anterior to the gonopore. Tracheal spiracle well-sclerotized. Total length 3.85. Cephalothorax 1.75 long, 1.50 wide, 1.15 high. Abdomen 2.35 long, 2.00 wide, 1.85 high. Sternum 1.00 long, 0.95 wide. Eye diameters and interdistances: AME 0.12. ALE 0.12. PME 0.15. PLE 0.13. AME-AME 0.11, AME-ALE 0.16, PME-PME 0.17, PME-PLE 0.16, ALE-PLE 0.01. Clypeus height 1.70. Chelicerae with the same coloration of the cephalothorax. Three promarginal and four retromarginal teeth ( Figs. 119D–F ). Ret1 with a basal enlargement ( Fig. 119D ). Leg measurements: I: femur 2.80, patella 0.75, tibia 2.75, metatarsus 2.25, tarsus 1.10, total 9.65; II: 2.50, 0.65, 2.37, 2.10, 1.05, 8.67; III: 1.60, 0.50, 1.20, 1.25, 0.70, 5.25; IV: 2.00, 0.40, 1.95, 1.50, 0.75, 6.60. DTS 0.27. DTE 0.25. Tracheal system as in Figures 121D–G . Spinnerets as in Figures 121H–J . Genitalia without spermathecae ( Fig. 121 A –C ). Uterus externus rectangular, with a median projection ( Fig. 121 A, C ).

Variation. Male total length 3.2–3.7 (N = 5; average 3.5), cephalothorax length 1.5–1.7 (N = 5; average 1.6), femur I length 2.2–2.5 (N = 5; average 2.3). Female total length 3.7–4.5 (N = 5; average 3.9), cephalothorax length 1.6–2.0 (N = 5; average 1.8), femur I length 2.0–2.8 (N = 5; average 2.4).

Distribution. Known from São Paulo, Rio de Janeiro and Minas Gerais states in Brazil ( Fig. 135 ).

Additional material examined (N = 3). BRAZIL: Minas Gerais: Bocaina de Minas , [22º9´53.85´´S, 44º23´27.55´´W], elev. [1169m], 1–3.i.2008, E. H. Wienskoski leg., 1 immature ( MNRJ 5034 ) . Rio de Janeiro: Teresópolis, Parque Nacional da Serra dos Órgãos ,, [22º29´35´´S, 43º4´24´´W], elev. [1700m], 4.viii.1996, 1♀ ( MNRJ 6400 ) . São Paulo: São José do Barreiro, Parque Nacional da Serra da Bocaina , [22º43´S, 44º36´W], elev. [900m], 28.iv –3.v.2002, Equipe Biota leg., 1♀ ( IBSP 68554 ) .

Figures

FIGURE 118. Glenognatha timbira new species from Brazil (Paratypes, MNRJ 6598). A – D, male habitus. A, dorsal. B, lateral. C, ventral. D, frontal. E – H, female habitus. E, dorsal. F, lateral. G, ventral. H, frontal. Scale bars, 500 µm. TS: tracheal spiracle.

FIGURE 119. Glenognatha timbira new species from Brazil (Paratypes, MNRJ 6598). A – C, male left chelicerae. A, anterior. B, posterior. C, mesal. D – F, female left chelicerae. D, anterior. E, posterior. F, mesal. Scale bars, 200 µm. Prt: promarginal tooth. Ret: retromarginal tooth.

FIGURE 120. Glenognatha timbira new species from Brazil (Paratype, MNRJ 6598). A – D, male left palp, schematic. A, ventral. B, conductor, ventral. C, conductor, dorsal. D, embolus, ventral. E – H, male left palp. E, ventral. F, dorsal. G, prolateral. H, retrolateral. Scale bars, 100 µm. C: conductor. CB: cymbium. CRa: conductor retrolateral apophysis. E: embolus. ED: ejaculatory duct. EMg: embolic medial groove. P: paracymbium. T: tegulum. TO: tarsal organ.

FIGURE 121. Glenognatha timbira new species. A – C, female genitalia. A, dorsal (arrow, median projection). B, ventral. C, lateral (arrow, median projection). D – G, female tracheal system. D, dorsal. E, median and lateral trunks. F, tracheal spiracle, posterior view. G, median trunk distal. H, ALS. I, PMS. J, PLS. Scale bars, 100 µm (A – E), 10 µm (F – J). AC: aciniform gland spigot. AG: aggregate gland spigots. CY: cylindrical gland spigot. FL: flagelliform gland spigot. LT: lateral trunk. MAP: major ampullate gland spigot. mAP: minor ampullate gland spigot. MC: membranous chamber. MT: median trunk. PI: piriform gland spigots. UE: uterus externus. TAG: tracheal atrium gland.

FIGURE 135. Distribution of G. vivianae new species, G. timbira new species and G. australis.