type Xenoctenus unguiculatus Mello-Leitão, 1938; gender masculine

N.B.: removed from the synonymy of Tunabo Chamberlin, 1916 (now a synonym of Neoctenus, family Trechaleidae) by Silva-Dávila, 2003: 32 (contra Lehtinen, 1967: 272) and considered a close relative of some taxa currently placed in Odo Keyserling, 1887; transferred from the Ctenidae to the Xenoctenidae (as its type genus) by Wheeler et al., 2017: 609.

In synonymy:
Xenoctenus marmoratus Mello-Leitão, 1941 = Xenoctenus unguiculatus Mello-Leitão, 1938 (Faustino-Magalhaes, Piacentini & Santos, 2024: 520).

Nomen dubium:
Xenoctenus patagonicus Mello-Leitão, 1940b: 40, f. 39 (j, Argentina) -- Carcavallo & Martínez, 1967: 76.

Xenoctenus gomezraggioi Carcavallo & Martínez, 1967: 79, f. 3-4 (Dmf).

Xenoctenus kaatinga Faustino-Magalhaes & Santos, in Faustino-Magalhaes, Piacentini & Santos, 2024: 531, f. 11A-D, 12A-D, 13C-D (Dmf).

Xenoctenus pampeanus Mello-Leitão, 1940b: 39, f. 37-38 (Dm).
Xenoctenus pampeanus Carcavallo & Martínez, 1967: 78, f. 1, 5, 8 (m).

Xenoctenus proseni Carcavallo & Martínez, 1967: 80, f. 7, 9-10 (Df).

Xenoctenus unguiculatus Mello-Leitão, 1938a: 101, f. 16-17 (Df).
Xenoctenus marmoratus Mello-Leitão, 1941d: 160, pl. 8, f. 38 (Df) [urn:lsid:nmbe.ch:spidersp:019382].
Xenoctenus marmoratus Prosen, 1951: 57, f. 1-3 (Dm).
Xenoctenus marmoratus Lehtinen, 1967: 457, f. 407 (f).
Xenoctenus unguiculatus Carcavallo & Martínez, 1967: 76 (type is juvenile, species inquirenda - taken here as nomen dubium, in accordance with Platnick's praxis).
Xenoctenus marmoratus Carcavallo & Martínez, 1967: 78, f. 2, 6 (mf).
Xenoctenus unguiculatus Faustino-Magalhaes, Piacentini & Santos, 2024: 520, f. 1F, 2A-D, 3A-D, 4A-D, 5A-C, 6A-D (mf, removed from nomen dubium, S of Xenoctenus marmoratus).

Horioctenus vittatus Mello-Leitão, 1936a: 27, pl. 2, f. 50 (Df; S of Horioctenus with Odo by Lehtinen, 1967: 239).
Xenoctenus vittatus Faustino-Magalhaes, Piacentini & Santos, 2024: 526, f. 1A-E, 7A-D, 8A-C, 9A-F, 10A-B, 13A-B (Dm, f, T from Odo).