Brachyauchenus castaneus Brunner von Wattenwyl 1895
Creators: name: Cadena-Castañeda, Oscar J.
name: Rodríguez, Nixon Oscar Parra
name: Res, Gustavo Costa Tava-
name: Rodríguez, Diana Marcela Trujillo
name: Arias, Ronald Fernando Quintana
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Orthoptera
Tettigoniidae
Brachyauchenus
Brachyauchenus castaneus

description: Brachyauchenus castaneus Brunner von Wattenwyl, 1895   
(Figs. 1–6)  
http://lsid.speciesfile.org/urn:lsid: Orthoptera.speciesfile.org:TaxonName:5035  
 Redescription. Male. General coloration reddish-brown (Fig. 1); in life, the face is grayish-green (when preserved in alcohol, this coloration disappears); in museum specimens, the face is reddish-brown (Fig. 1C). Dorsal surface of the stridulatory area of both wings distinctly black, bordered by a light-yellow line (Figs. 1B, 2A, 2B). Costal area of the tegmina is blurred and outlined by black regions, forming yellowish triangular portions that contrast with the rest of the tegmina (Fig. 1A). Body covered by abundant hairs on all its surface (Fig. 1). Head. Frons and vertex smooth, quite narrow fastigium; in dorsal view, a little bit shorter than the margins of the antennal sockets, and dorsally sulcate. Lateral ocelli reduced and not very visible between antennal basins and fastigium; frontal ocellus very reduced, inconspicuous being only a small diffuse point between the antennal sockets; eyes rounded both in lateral or frontal view; antennal scape with a spine at the apex on the dorsal margin, pedicel unarmed. Pronotum notably granulated, pronotal disc flat, with deep grooves, with anterior margin projected onto the neck and with a more conspicuous distal granulation; posterior margin straight (Fig. 1B); ventral margin of lateral lobes thick, remarkably widening from the anterior to the posterior border, and separated from the propleura (Figs. 1A, 1B). Sternum. Proesternum armed with two triangular and conspicuous spines; mesosternum rectangular, and with a tubercle elevated on each margin of the lateral lobe; metasternum without elevated tubercles. Legs. Fore-femur ventrally armed with four spines only on the inner margin; fore-tibia armed with seven spines on each ventral margin. Mid-femur with five ventral spines on the outer margin and mid-tibia with seven ventral spines on each ventral margin. Hind femur with seven ventral spines on the outer margin; hind tibia with ten dorsal spines on each margin, and twelve spinules on the ventral margins. All genicular lobes armed, except the outer genicular lobe of the mid-femur; all spines of the femora and hind tibiae black (Fig. 1A, 1C). Wings not surpassing the apex of the abdomen, reaching the sixth or seventh abdominal segment. Veins M and R of the tegmina never converge, and Rs vein originating near the apex of the tegmina (Figs. 1A, 1B). Left stridulatory file (= vein A1) short, almost straight, but with the distal third (towards the anal margin) notably sinuous, bearing 155‒160 elongated and flattened teeth (Fig. 2C). When the tegmina are at rest position, the stridulatory file is covered under the pronotum (Fig. 2A). Mirror on the right tegmen ovoid and small (Fig. 2B); non-functional stridulatory file of the right tegmen ventrally in the form of a fold with few and small visible denticulations. Hindwings faded brown. Abdomen. Tenth tergite unmodified, without prolongation nor any ornamentation, cupuliform (Figs. 2D, 2F), with the division between the tenth tergite and the epiproct little differentiated (Fig. 2G). Epiproct ovoid, membranous and strongly attached to the paraprocts, with a longitudinal groove on the dorsal region and rounded posterior border (Fig. 2G). Cerci tumescent, cylindrical with a small distal inward spine (Fig. 2D). Subgenital plate mostly rectangular, narrow, notably longer than wide, and with a deep and narrow U-shaped notch (Fig. 2E), styli as long as the subgenital plate, upcurved and club-shaped (Figs. 2E, 2F). Male genitalia. Lateral edges produced into two lobes corresponding to the lw.vl.; up.vl reduced in dorsal view; df narrow, dl with divergent lateral margins from the distal portion to the base, internally with various microstructures like small denticulations; ti tubular and with two distal-lateral regions with microstructures like small scales; ejv ovoid and connected by a small conduit internally to the ejd.   
 Female (nov). Similar in shape and color to the male (Fig. 4), but the tegmina reach only the fifth abdominal segment (Fig. 4A, 4B). Tenth tergite with a slightly concave posterior margin, flanked by two small prolongations; epiproct with a semicircle shape, wider than long and with a rounded posterior border (Fig. 5A); cerci cylindrical, progressively tapering towards the apex (Figs. 5A, 5B). Subgenital plate triangular, at the apex with a small notch (Fig. 5C). Ovipositor a little longer than the hind femur, slightly curved, and with an acuminated apex (Fig. 5B). Dorsal valve with serrulations from the middle to the apex, and ventral margin of the lower valve convex (Fig. 5B).   
 Variation. The studied specimens did not show significant variations, the number of spines on the legs did not vary in number. A female had the hind femur with black and gray spots (Fig. 6), which, when placed in alcohol, disappeared, acquiring the same coloration as the rest of the body, as happened with museum specimens. Possibly this coloration is lost post-mortem, as occurs with the coloration of the face.   
 Type specimen. Holotype. Male, Colombia, Sta. Fe de Bogotá, Alen Linding. Code. 4808 Naturhistorisches Museum Wien (NMW).   
 Specimens examined. 1 male and 1 female, Colombia, Boyacá, Coper, Vereda Turtur, Sector San Ignacio, 1600 m. 5°25’32.03”N, 74° 0’15.24”W. December 2015. O.J. Cadena-Castañeda leg. (CAUD) 1 male, Cundinamarca, Pacho, 1680 m. 5° 9’14.32”N, 74° 9’8.61”W. October 2009 (CAUD). 1 female, Santander, Oiba, 1790m. 6°14’12.21”N, 73°16’58.55”O (CAUD). 1 male and 1 female, Santander, Charalá, Virolín, 6°17’14,10”N, 73°9’10,7”W. ICN-OR 00973 and ICN-OR 00984 (ICN). 1 male, Santander, San José de Suaita, 1500m. 9 May 1999, 6.167 6, -73.4672 (Det. H. Braun, December, 2009) (ICN).   
 Measurements (mm). Male / Female: LB: 30–33/38–40, Pr: 6.5–7/8–8.5, Teg: 21–23/27–29, HF: 16– 16.5/17–18, HT: 17.5–18/19–20, SP: 4.5–5/2–2.5, Ov: 20–21.   
 Comments. The female of the species is reported and described for the first time, with additional material (until now only the male type specimen was known). According to the specimens collected in Coper, Boyacá, it was observed that they have twilight and nocturnal activity, being present in the vegetation and tree trunks at the understory level, preferring humid areas. When they were collected, the male sang, and due to the visible movement of its wings and the fact that the sound was not audible to a large extent, its song must be mostly ultrasonic. Unfortunately, it was not possible to record the specimen on that occasion. With specimens collected in Santander, it was observed that, during the day, they prefer to be between holes in the trunks, with the forelegs and the antennae arranged forward and the mid and hind legs backward (Fig. 6).   
 The type locality of the species was originally Santa Fe de Bogotá (former name of the capital of Colombia, now known only as Bogotá) (Chamorro-Rengifo et al., 2011). However, the place is above 2500–2650 m., with a cold climate, unlike the other reliable records of the specimens studied here, of middle lands with a warm climate between Cundinamarca, Boyacá, and Santander (Fig. 9). Possibly, the type specimen could be collected in midland localities near Bogotá. However, at that time, collectors used to mention that the specimens were sampled in more recognized towns or cities of Colombia, even if the collection places were many kilometers away from the locality mentioned on the specimens labels, with flora, elevation, and conditions very different (Rehn, 1930).   
 A recent case that corroborates the statement presented here, concerns Bactrophora dominans Westwood, 1842. The locality of this species is “ Santa Fe de Bogotá ”, but this species inhabits the Amazon rainforests and localities of the Guyanese shield, where the biomes are opposite to those found in the Bogotá savanna, or the rest of the Cundiboyacense highlands. For this reason, that record was not taken into account by entomologists (Rehn, 1930; Silva et al., 2021), and, for the same reason, we discarded the presence of B. castaneus in the forests that surround the city of Bogotá.
description: Published as part of Cadena-Castañeda, Oscar J., Rodríguez, Nixon Oscar Parra, Res, Gustavo Costa Tava-, Rodríguez, Diana Marcela Trujillo & Arias, Ronald Fernando Quintana, 2021, Studies on Neotropical Pseudophyllinae: The status of the genus Brachyauchenus Brunner von Wattenwyl, 1895 and its species (Orthoptera: Tettigoniidae: Pseudophyllinae: Platyphyllini), pp. 546-562 in Zootaxa 5027 (4) on pages 549-556, DOI: 10.11646/zootaxa.5027.4.4, http://zenodo.org/record/5453427