Myrmecotypus tahyinandu Perger & Rubio, 2020

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), Zootaxa 5555 (4), pp. 451-496 : 462

Myrmecotypus tahyinandu Perger & Rubio, 2020

Figs 6A–J, 7A–G

Myrmecotypus tahyinandu Perger & Rubio, 2020: 155 , Figs 1C, D, 4–6, 7B (holotype, ♂, BOLIVIA: Santa Cruz department: Andrés Ibáñez province, La Guardia; in Instituto de Biología Subtropical , Misiones, Argentina; IBSI-Ara1469, not examined)

Note. The Brazilian specimens bear no significant differences in the genitalia in relation to the Bolivian specimens reported in the original description. However, they have coxae I and II white, while, according to Perger & Rúbio (2020), the Bolivian species have only the coxae II white. Similar variations occur in M. dacetonoides comb. nov. and M. atratoides spec. nov. Therefore, our decision regarding this identification was based on the taxonomic principle of parsimony, since the alternative would be producing a possibly unnecessary specific name for the Brazilian specimens, based on a single character that was demonstrated to be variable in other species of the genus. This decision must be tested by molecular studies.

Diagnosis. Myrmecotypus tahyinandu resembles M. rapaxoides spec. nov. by an elongated and narrow thoracic region and by the sperm duct with almost the same width as the embolus but differs by the completely dark abdomen ( Fig. 6A–C). Males differ by the presence of the prolateral pre-embolic ridge and keels in the embolus ( Fig. 6G), which are absent in M. rapaxoides spec. nov. ( Fig. 24G, H). Females resemble those of M. rapaxoides spec. nov. by the recurved epigynal transverse ridge, with a large marginal sclerotized area, but differ by the presence of a groove below the epigynal ridge ( Fig. 6I), which is absent in M. rapaxoides spec. nov. ( Fig. 24I).

Description. See Perger & Rubio (2020).

Variation. Perger & Rubio (2020) noticed that, in the Bolivian specimens, only the coxa II is translucent-white (their fig. 5); the specimens from Brazil here examined have coxae I and II white ( Fig. 6C, F). This difference is here interpreted as intraspecific variation, as observed in M. dacetonoides comb. nov. and M. atratoides spec. nov. too.

New records. BRAZIL: Mato Grosso: Rios Araguaias e Tapinapés , [11°42’12.3”S, 50°42’12.0”W], 1♂, 30.XI.1960, B. Malkin leg. ( MCN) ; São Paulo: Presidente Epitácio, Usina Hidrelétrica Engenheiro Sergio Motta [22°28’45.2”S, 52°57’27.2”W], 1♀, 16.I–13.II.1999, Eq. IBSP leg. ( IBSP, IB-23081 ) ; Rio Grande do Sul: Porto Esperidião [15°53′10’’S, 58°58′15’’W], 4♀ 2♂, XI.1984, Magno & Alvarenga leg. ( MNRJ 18390 ) .

Distribution. Bolivia and Brazil ( Fig. 25)