Myrmecotypus balerion Silva-Junior & Bonaldo, 2024, spec. nov.
Creators: name: Silva-Junior, Cláudio J.
name: Bonaldo, Alexandre B.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Corinnidae
Myrmecotypus
Myrmecotypus balerion

description: Myrmecotypus balerion spec. nov.
Figs 20A–J, 21A–I
Type material. BRAZIL: ♂ holotype, Pará, Juruti, 02°24’20.7”S, 56°26’00.3”W, 18.IX.2002, D. Guimarães leg. (MPEG (ARA)-003429).
Paratypes: BRAZIL: Pará, Juruti, 02°24’20.7”S, 56°26’00.3”W, 1♀, 18.IX.2002, D. Guimarães leg. (MPEG (ARA)-003429); Pará, Juruti, 02°24’03’’S, 56°25’45.0’’W, 1♀, 19.XI.2002, A.B. Bonaldo leg. (MPEG (ARA)003426).
Etymology. The specific name refers to Balerion, The Terrible, a fictional creature in R.R. Martin’s book series “A Song of Ice and Fire”.
Diagnosis. Myrmecotypus balerion spec. nov. differs from all other Myrmecotypus by the presence of a small dorsal depression on the thoracic region at the level of the leg III insertion (Figs 20B), tibia I ventral spination 4- 3, male palp with a long, flat and unsclerotized RTP (Fig. 20G, H); females can be recognized by the continuous epigynal transverse ridge bearing a median T-shaped sclerotization (Fig. 20I).
Description. Male (MPEG(ARA)-003429). Total length 4.97. Carapace 2.73 long, 1.21 wide. Sternum 1.24 long, 0.51 wide. Abdomen 1.98 long, 1.31 wide. Eye diameters: AME 0.12, ALE 0.07, PME 0.06, PLE 0.07. Eye inter-distances: AME-AME 0.10, AME-ALE 0.03, ALE-PLE 0.20, PME-PME 0.19, PME-PLE 0.13, AME-PME 0.08. Carapace long and narrow, brown with dark-brown spots, somewhat narrowed in head region, with weak constriction between the cephalic and thoracic regions, anterior margin truncated with the slightly rounded tips, lateral margins with two very slight depressions, thoracic region higher than cephalic region, with very slight depression on its surface (Fig. 20B). Feathery hairs present in ocular area and on sides of carapace (Fig. 21A). Endites light brown, with promargin yellowish-brown, labium brown. Chelicerae yellowish-brown, with dark-brown spots, three promarginal teeth of different sizes and two retromarginal teeth, largest, equal and equidistant. Sternum elongate, narrower between legs III and IV, with feathery hairs (Fig. 20C). Abdomen with dorsal scute reddish-brown, longer than wide and with feathery hairs. Lightly present pedicel collar (Fig. 21G). Ventral scute brown, quadrangular-shaped, not extending to spinnerets. Tracheal scute present, brownish-black. Only coxa II translucent white. Coxae III and IV yellowish-brown, coxae I yellowish-brown but clear at the center. Femur I brown dorsally and ventrally, white on promargin and retromargin. Patella and tibia yellow dorsally and ventrally, light brown on promargin and retromargin. Metatarsus brown and tarsus yellow. Legs III and IV brown, with patella yellow ventrally. Leg measurements: I—femur 1.34 / tibia 1.15 / metatarsus 0.95; II—femur 1.19; III—femur 1.20; IV—femur 1.83 / tibia 1.64. I-femur do 0-0-0-1, pl 0-0-0-1,; tibia ve 1p-2-2-2 (4-3); metatarsus ve 2-2/ II-femur do 1-0-0-1, pl 0-1-0-0, rl 0-1-0-0; tibia ve 2-2; metatarsus ve 2-2/ III-femur do 0-0-1-1; pl 0-1-1, rl 0-1-1; tibia do 0-0-1, pl 0-1-1, rl 0-1-1, ve 2-2; metatarsus pl 1-1-0-1, rl 1-1-0-1, ve 2-2-2-1/ IV-femur do 1-0-1-1, pl 0-0-0-1, rl 0-0-0-1; tibia do 0-0-1, pl 1-0-1, rl 1-0-1, ve p 1-0-1; metatarsus pl 1-1-0-1, rl 1-1-0-1, ve 2-2. Palp with RTA spiniform; globose genital bulb drawn into neck followed by long, flat retroapical tegular projection; embolus very short (Fig. 20G, H).
Female (paratype MPEG(ARA)003426). Total length 5.47. Carapace 2.89 long, 1.27 wide. Sternum 1.27 long, 0.18 wide. Abdomen 1.99 long, 1.35 wide. Eye diameters: AME 0.10, ALE 0.04, PME 0.07, PLE 0.06. Eye inter-distances: AME-AME 0.12, AME-ALE 0.04, ALE-PLE 0.23, PME-PME 0.25, PME-PLE 0.22, AME-PME 0.12. Carapace long and narrow, brown, with dark brown spots, somewhat narrowed in cephalic region, with moderate constriction between cephalic and thoracic regions, thoracic region with very slight depression on its surface, anterior margin truncated, lateral margins with two very slight depressions. Feathery hairs cover entire carapace but heavily distributed in ocular area and on sides (Fig. 20D). Endites brown, with promargin yellow, labium brown. Chelicerae brown, dark-brown spots, three promarginal teeth of different sizes and two retromarginal teeth largest equal and equidistant. Sternum elongate, narrower between legs III and IV, with feathery hairs. Abdomen oval, with dorsal scute brown, moderately small. Pedicel collar weakly developed (Fig. 20D). Feathery hairs covered as in male. Ventral scute absent. Tracheal scute reddish-brown. Leg coloring as in male (Fig. 20F). Leg measurements: I—femur 1.24 / tibia 1.20 / metatarsus 0.92; II—femur 1.15 / tibia 1.25 / metatarsus 0.81; III—femur 1.12 / tibia 0.89 / metatarsus 0.88; IV—femur 1.87 / tibia 1.28 / metatarsus 1.44. Spination: I-femur do 0-0-0-1, pl 0-0-0-1,; tibia ve 1p-2-2-2 (4-3); metatarsus ve 2-2/ II-femur do 1-0-0-1, pl 0-1-0-0, rl 0-1-0-0; tibia ve 2-2; metatarsus ve 2-2/ III-femur do 0-0-1-1; pl 0-1-1, rl 0-1-1; tibia do 0-0-1, pl 0-1-1, rl 0-1-1, ve 2-2; metatarsus pl 1-1-0-1, rl 1-1- 0-1, ve 2-2-2-1/ IV-femur do 1-0-1-1, pl 0-0-0-1, rl 0-0-0-1; tibia do 0-0-1, pl 1-0-1, rl 1-0-1, ve p 1-0-1; metatarsus pl 1-1-0-1, rl 1-1-0-1, ve 2-2. Epigyne with continuous transverse ridge bearing median T-shaped sclerotization. Vulva with globose spermathecae flowed by moderately short neck. Copulatory duct thin, inserted laterally in spermathecae (Fig. 20I, J, 21I).
Variation. Length (2♂) total 5.26–5.36, carapace 2.90–2.98, femur I 1.14–1.18; (3♀) total 5.50–5.85, carapace 2.47–3.04, femur I 1.04–1.28.
Other material. BRAZIL: Amazonas: Manaus, Ilha de Curari [03°19’53.2’’S, 60°05’07.3’’W], 1♂, 3.VIII.1979, J. Adis et al. (IBSP, IB-17311); Pará: Juruti 02°24’33.2’’S, 56°26’10.6’’W, 1♂ 4♀, 17.IX.2002, A.B. Bonaldo leg. (MPEG (ARA)-003422); Same data but 1♀, 17.IX.2002 (MPEG (ARA)-003423); Same data but 1♀, 17.IX.2002 (MPEG (ARA)-003430); Same data but 1♂ 1♀, 18.IX.2002 (MPEG (ARA)-003428); Same data but 1♂, 19.IX.2002 (MPEG (ARA)-003287); Same data but 1♂, 19.IX.2002 (MPEG (ARA)-003290); Same data but 1♂, 19.IX.2002 (MPEG (ARA)-003290).
Distribution. States of Amazonas and Pará, Brazil (Fig. 26).
description: Published as part of Silva-Junior, Cláudio J. & Bonaldo, Alexandre B., 2024, A revision of the South American species of the ant-mimicking spider genus Myrmecotypus O. Pickard-Cambridge, 1894 (Araneae: Corinnidae: Castianeirinae), pp. 451-496 in Zootaxa 5555 (4) on pages 483-485, DOI: 10.11646/zootaxa.5555.4.1, http://zenodo.org/record/14594905