Bioacoustics of Rhumosa

Description. Superficially similar to Lutosa Walker, 1869 (c.f. diagnosis). Body size average for the subfamily. Body laterally flattened; shiny, without conspicuous setae. Male and females with no sexual dimorphism except in the genital area. Color. General coloration shiny brown, tarsi and anterior ventral angle of pronotum lighter in all species ( Fig. 96 – 100 ). Head. Head in front view much higher than wide, as wide in ocular area as in mandibular area, genae subparallel ( Fig. 1, 5, 9, 13, 17 ). Fastigium verticis as wide ( Fig. 8 ) or wider ( Fig. 16 ) as scapus; compressed between lateral ocelli; ending variable, pointing ( Fig. 4 ), or broadly rounded ( Fig. 16 ). Fastigium frontis contacting the fastigium verticis in a narrow point ( Fig. 4, 8, 12, 16, 20 ). Ocelli well distinct ( Fig. 1, 5, 9, 13, 17 ). Carinae lateralis externa not distinct; carinae lateralis interna distinct in sideview ( Fig. 3, 7, 11, 15, 19 ). Scapus non armed. Thorax. Pronotum not fully covering mesonotum, lateral lobes angulose between ventral and posterior borders, but without projection ( Fig. 3, 7, 11, 15, 19 ). Anterior margin more or less straight in dorsal view ( Fig. 2, 6, 10, 14, 18 ). Wings. Absent. Legs. Fore coxa with one median antero lateral spine (e.g. Fig. 1, 19 ). Fore femora non-armed. Fore tibia ( Fig. 21, 25, 29, 33, 37 ): with 1 – 2 dorsal inner subapical spurs (in addition to 1 dorsal inner apical spur); with 2 dorsal outer subapical spurs (in addition to 1 dorsal outer apical spur); with 4 ventral inner subapical spurs (in addition to 1 ventral inner apical spur); with 4 ventral outer subapical spurs (in addition to 1 ventral outer apical spur); with one oval tympanic aperture on each side. Mid femora non-armed. Mid tibia ( Fig. 22, 26, 30, 34, 38 ): with 2 dorsal anterior subapical spurs (in addition to 1 dorsal anterior apical spur); with 3 dorsal posterior subapical spurs (in addition to 1 dorsal posterior subapical spurs); with 4 ventral inner subapical spurs (in addition to 1 ventral inner apical spur); with 3 ventral outer subapical spurs (in addition to 1 ventral outer apical spur). Hind femora ( Fig. 23, 27, 31, 35, 39 ): outer genicular lobe with one ventral spine more or less conspicuous; inner genicular lobe with 1 apical spine; external surface with 11 – 14 chevron ridges. Hind tibia ( Fig. 24a, 28a, 32a, 36a, 40a ): with 1 minute ventral subapical spur after the middle; with 11 – 14 dorsal outer subapical spines; with 10 – 13 dorsal inner subapical spines. Abdomen. Laterally flattened. Without conspicuous stridulatory pegs. Male. X th abdominal tergite ( Fig. 44, 49, 54, 59, 64 ): forming two vertical trapezoid lobes (hardly visible in dorsal view, Fig. 42, 47, 52, 57, 62 ); lobes dorso-ventrally oriented; with one minute median dorsal/proximal hook on each lobe ( Fig. 44, 49, 54, 59, 64 ); contact of the two lobes forming a long vertical suture below the hooks ( Fig. 44, 49, 54, 59, 64 ). Epiproct more or less visible in dorsal view ( Fig. 42, 47, 52, 57, 62 ); anterior part triangle shaped, posterior margin variable ( Fig. 44, 49, 54, 59, 64 ); directly nested between lobes of X th abdominal tergite, without membranous area separating them. Paraprocts ( Fig. 69, 73, 77, 81, 85 ) very small, with a minute sclerotized median projection; hidden under epiproct ( Fig. 44, 59, 64 ) or hardly visible ( Fig. 49, 54 ). Subgenital plate ( Fig. 43, 48, 53, 58, 63 ): broadly rounded or more angulose in ventral view, with a median proximal membranous area; with a distinct ventral carina ( Fig. 45, 50, 55, 60, 65 ); with small styli; distal border of plate not armed on lateral angles (more lateral to styli insertion); distal border of plate with two spines between styli ( Fig. 45, 50, 55, 60, 65 ). Epiphallic apodemes much developed, turned inwards posteriorly ( Fig. 66, 70, 74, 78, 82 ). Female. Subgenital plate (87, 89, 91, 93, 95): triangular, without emargination. Ovipositor ( Fig. 86, 88, 90, 92, 94 ): ventral valves straight in the proximal quarter, and regularly up curved distally.