Ami Pérez-Miles

Pérez-Miles, Fernando, Gabriel, Ray, Miglio, Laura, Bonaldo, Alexandre, Gallon, Richard, Jimenez, Juan Jacobo & Bertani, Rogerio, 2008, Ami, a new Theraphosid genus from Central and South America, with the description of six new species (Araneae: Mygalomorphae), Zootaxa 1915, pp. 54-68 : 55-56

Ami Pérez-Miles , gen. nov.

Type species: Ami caxiuana Pérez-Miles, Miglio & Bonaldo , sp. nov.

Etymology: Ami is a noun in apposition from the Tupí language (which means a spider that does not spin a web); the gender of Ami as feminine.

Diagnosis: Ami males differ from those other of theraphosid genera by the presence of one or two distal sub-conical processes on the retrolateral surface of the male palpal tibia ( Figs 1–4 , 22, 23, 32 ). Males and females with modified Type I abdominal urticating hairs ( Fig. 43 ), with area b longer than previously described ( Cooke et al. 1972), similar to those found in Proshapalopus Mello-Leitão 1923 ( Bertani 2001) and Citharacanthus livingstoni Schmidt & Weinmann 1996 holotype (R.B. pers. obs.). Female of Ami differ further from those of all other theraphosines by their highly characteristic spermathecae with paired ventral receptacles attached to an almost discrete, semicircular, sclerotized back-plate ( Fig. 9 ). Males also differ from those of other theraphosids by the palpal organ morphology, having prolateral keels that are more or less convergent.

Affinities: The modified type I urticating hairs of Ami resemble that in Proshapalopus from which it differs in the general palpal organ morphology, especially in lacking subapical keel, and in the presence of retrolateral processes in male palpal tibia. Also Citharacanthus livingstoni has modified type I urticating hairs (R.B. pers. obs.) but there are several differences between this genus and Ami such us prolateral keels poorly developed, distal part of palpal organ more narrow and presence of stridulatory bristles. Both Proshapalopus and Citharacanthus lack the sclerotized back-plate in spermathecae as in Ami .

Description. Carapace ovate, hirsute, light to dark brown. Caput slightly arched. Fovea short transverse, straight to slightly procurved. Eyes group subquadrate to wider than long, tubercle well-defined. Clypeus narrow. Chelicerae normal, with 8–11 teeth on promargin of furrow, basomesally 11–14 small teeth. Labium wider than long, suture broad, with reduced number of cuspules. Maxillae longer than wide, slightly setose, prolateral anterior angle slightly produced, number of cuspules reduced, distributed along proximal edge, mostly on prolateral angle. Sternum as long as wide, sigilla small oval, submarginal. Stridulatory bristles absent. Legs moderately stout, hirsute, with or without ( A. yupanquii ) homogenous color pattern, spines present except on femora. Paired claws on legs and claw tufts well-developed. All tarsi with scopula, metatarsi with distal scopulae or ascopulate (usually metatarsi IV). Abdomen hirsute, without pattern, modified type I urticating hairs present, type III urticating hairs absent. PMS well-developed; PLS small, apical segment domed. Males with two (most species) or one ( A. pijaos ) retrolateral processes on palpal tibiae. Palpal organ piriform, with subtegulum extended, prolateral superior and prolateral inferior keels present and an additional small keel between them ( A. caxiuana , A. pijaos ). Tibia I with paired distal proventral apophysis. Spermathecae with back flattened sclerotized atrium with or without coniform or tubuliform receptacles.

Figures

FIGURES 1 – 16. Ami species. 1 – 4. Left palpal tibiae, males, dorsal view, showing two retrolateral processes. 1. Ami obscura; 2. Ami bladesi; 3. Ami yupanqui; 4. Ami caxiuana. 5 – 6. Ami caxiuana, dorsal view. 5. Male; 6. Female. 7 – 8. Left palpal organ, A. caxiuana, male. 7. Prolateral view, showing keels and granular area; 8. Retrolateral view. 9. A. caxiuana, spermathecae, ventral view. 10. A. caxiuana, left tibial apophyses, male, proventral view. 11 – 13. A. yupanquii, male, left palpal organ. 11. Prolateral view showing ventral flattened area (on left); 12. Retrolateral view; 13. Dorsal view. 14. A. yupanquii, male, left tibial apophyses, proventral view. 15. A. yupanquii, spermathecae, ventral view. 16. A. bladesi, male, left tibial apophyses, proventral view.

FIGURES 17 – 38. Ami species. 17 – 18. A. bladesi, male, left palpal organ,. 17. Prolateral view; 18. Retrolateral view. 19 – 20. A. obscura, male, right palpal organ. 19. Retrolateral view, 20. Prolateral view. 21. A. obscura, male, right tibial apophyses, proventral view. 22 - 23. Ami pijaos, male, left palpal tibiae, showing retrolateral process. 22. Dorsal view; 23. Ventral view. 24 – 27. A. pijaos, male, left palpal organ. 24. Prolateral view. 25. Retrolateral view; 26. Prodorsal view. 27. Retrodorsal view. 28. A. pijaos, male, left tibial apophyses, proventral view. 29. A. pijaos, spermathecae, ventral view. 30. Ami amazonica, female, dorsal view. 31. A. amazonica, spermathecae, ventral view. 32. A. weinmanni, male, left palpal tibia, dorsal view, showing two retrolateral processes. 33. A. weinmanni, male, left tibial apophyses, proventral view. 34 – 35. A. weinmanni, male, left palpal organ. 34. Prolateral view; 35. Retrolateral view. 36. A. weinmanni, spermathecae, ventral view. 37 – 38. Ami weinmanni, dorsal view. 37. Male; 38. Female.

FIGURES 39 - 45. Ami species. 39. A. yupanquii, female, habitus. 40. A. bladesi, male, habitus. 41. A. pijaos, male, habitus. 42. A. amazonica, female, habitus. 43 – 44. Ami weinmanni, female tarsus II, ventral view. 43. Tarsal scopula with distal rhomboidal group of longer setae. 44. Close-up of distal tarsal scopula showing group of longer setae. 45. A. weinmanni, male, modified Type I abdominal urticating hairs, with area b longer than usual.