type Theridium fordum Keyserling, 1884; gender neuter; syn. of Tidarren sisyphoides (Walckenaer, 1841)

N.B.: not a senior synonym of Echinotheridion Levi, 1963 (Wunderlich, 1992a: 410, contra Wunderlich, 1987).

Transferred to other genera:
Tidarren cartum (Levi, 1963) -- see Echinotheridion
Tidarren fordum luctuosum Caporiacco, 1954 -- see Cryptachaea
Tidarren gibberosum (Kulczyński, 1899) -- see Echinotheridion
Tidarren incertissimum Caporiacco, 1954 -- see Theridion
Tidarren rostratum (O. Pickard-Cambridge, 1896) -- see Cryptachaea

In synonymy:
Tidarren amilcari (Barrientos & Hernández-Corral, 2021, T from Cryptachaea) = Tidarren cuneolatum (Tullgren, 1910) (Hernández-Corral & Barrientos, 2021b: 53).
Tidarren ansatum (Walckenaer, 1841, T from Theridion) = Tidarren sisyphoides (Walckenaer, 1841) (Levi, 1957a: 21).
Tidarren chevalieri (Berland, 1936) = Tidarren cuneolatum (Tullgren, 1910) (Knoflach & van Harten, 2006: 1515).
Tidarren elevatum (Banks, 1897) = Tidarren haemorrhoidale (Bertkau, 1880) (Levi, 1969: 71).
Tidarren fordulum (Banks, 1909) = Tidarren haemorrhoidale (Bertkau, 1880) (Levi, 1969: 71).
Tidarren fordum (Keyserling, 1884, T from Theridion) = Tidarren sisyphoides (Walckenaer, 1841) (Chamberlin & Ivie, 1944: 57).
Tidarren guineense (Simon, 1907, T from Theridion) = Tidarren scenicum (Thorell, 1899) (Knoflach & van Harten, 2006: 1567).
Tidarren hagemanni Schmidt, 1956 = Tidarren cuneolatum (Tullgren, 1910) (Wunderlich, 1992a: 410, sub T. chevalieri).
Tidarren minor Chamberlin & Ivie, 1934 = Tidarren haemorrhoidale (Bertkau, 1880) (Levi, 1969: 71).
Tidarren probum (O. Pickard-Cambridge, 1899, T from Dipoena) = Tidarren sisyphoides (Walckenaer, 1841) (Levi, 1963a: 138).
Tidarren pseudogibberosum Schmidt, 1973 = Tidarren cuneolatum (Tullgren, 1910) (Wunderlich, 1992a: 410, sub T. chevalieri).
Tidarren texanum (Banks, 1910) = Tidarren haemorrhoidale (Bertkau, 1880) (Levi, 1969: 71).
Tidarren turrigerum (Simon, 1900, T from Theridion) = Tidarren scenicum (Thorell, 1899) (Knoflach & van Harten, 2006: 1567).

Nomen dubium:
Tidarren maculosum (Keyserling, 1884a: 30, pl. 1, f. 14, f, Venezuela, originally in Theridion) -- Levi, 1967b: 28, confirmed by Levi, 1969: 71.

Tidarren aethiops Knoflach & van Harten, 2006: 1548, f. 157-163, 172 (Df).

Tidarren afrum Knoflach & van Harten, 2006: 1551, f. 164-171, 173 (Df).

Tidarren apartiolum Knoflach & van Harten, 2006: 1575, f. 187, 194, 230-233 (Df).

Theridion cuneolatum Denis, 1955e: 2, f. 2-4 (f; misidentified per Knoflach & van Harten, 2006: 1506).
Tidarren argo Knoflach & van Harten, 2001: 450, f. 1-2, 3a-d, 4a-c, 7-8 (Dmf).
Tidarren argo Knoflach & van Harten, 2006: 1506, f. 7-8, 18-20, 22, 25-26, 31-33, 38, 41-44, 50a-b, 52-76, 154 (mf).
Tidarren argo Vanuytven, 2021: 18, 291, f. A.3c, B.325a-b (m).

Tidarren circe Knoflach & van Harten, 2006: 1556, f. 174, 196-199 (Df).

Theridion cuneolatum Tullgren, 1910: 132, pl. 2, f. 48 (Df).
Theridion chevalieri Berland, 1936: 82, f. 28-29 (Df) [urn:lsid:nmbe.ch:spidersp:008923].
Tidarren hagemanni Schmidt, 1956e: 146, f. 4-6, 6a (Dmf) [urn:lsid:nmbe.ch:spidersp:062916].
Tidarren pseudogibberosum Schmidt, 1973: 368, f. 5 (Df) [urn:lsid:nmbe.ch:spidersp:062919].
Tidarren hagemanni Wunderlich, 1987a: 208, f. 546 (f).
Tidarren chevalieri Wunderlich, 1987a: 208 (T from Theridion).
Tidarren chevalieri Wunderlich, 1992a: 410, f. 606 (f, S of Tidarren hagemanni and T. pseudogibberosum [removed from S of Tidarren = Echinotheridion gibberosum, rejecting Wunderlich, 1987a: 207]).
Tidarren chevalieri Schmidt, Geisthardt & Piepho, 1994: 93, f. 5-6 (m).
Tidarren cuneolatum Knoflach & van Harten, 2000b: 1641, f. 1-22 (mf, T from Theridion).
Tidarren cuneolatum Knoflach & Pfaller, 2004: 136, f. 19b, 21g (mf).
Tidarren cuneolatum Knoflach & van Harten, 2006: 1515, f. 2, 9, 11-15, 27, 34-35, 45-49, 78, 81-104, 121 (mf, S of Theridion chevalieri).
Tidarren cuneolatum Dippenaar-Schoeman et al., 2021A: 44, 3 f. (f).
Cryptachaea amilcari Barrientos & Hernández-Corral, in Hernández-Corral & Barrientos, 2021a: 40, f. 3-8 (Df) [urn:lsid:nmbe.ch:spidersp:053301].
Tidarren cuneolatum Hernández-Corral & Barrientos, 2021b: 53, f. 1a-b (f, S of Cryptachaea amilcari).
Tidarren cuneolatum Chamé-Vázquez & Villarreal, 2023: 232, f. 1A-F, 2A-D (mf).

Tidarren dasyglossa Knoflach & van Harten, 2006: 1577, f. 188-189, 234-238 (Df).

Tidarren dentigerum Knoflach & van Harten, 2006: 1528, f. 17, 79, 105-120 (Dmf).

Tidarren ephemerum Knoflach & van Harten, 2006: 1580, f. 239-242 (Dm).
Tidarren ephemerum Vanuytven, 2021: 291, f. B.325a (m).

Tidarren gracile Knoflach & van Harten, 2006: 1534, f. 80, 122-135, 156 (Dmf).

Tidarren griswoldi Knoflach & van Harten, 2006: 1559, f. 175, 200-203 (Df).

Theridion haemorrhoidale Bertkau, 1880a: 78 (Df).
Theridion elevatum Banks, 1897: 195 (Df; preoccupied by Thorell, 1881, see Theridion elevatum) [urn:lsid:nmbe.ch:spidersp:062921].
Steatoda elevata F. O. Pickard-Cambridge, 1902a: 387.
Theridion fordulum Banks, 1909a: 203 (D) [urn:lsid:nmbe.ch:spidersp:062914].
Theridion texanum Banks, 1910: 20 (replacement name for Theridion elevatum) [urn:lsid:nmbe.ch:spidersp:062920].
Tidarren minor Chamberlin & Ivie, 1934: 10, pl. 3 (Dm) [urn:lsid:nmbe.ch:spidersp:062917].
Tidarren minor Archer, 1950: 15, pl. II, f. 2 (m).
Tidarren mixtum Kraus, 1955b: 19, f. 45-48 (f; misidentified per Knoflach & van Harten, 2006: 1590).
Tidarren texanum Levi, 1957a: 21 (T from Theridion).
Tidarren fordum Levi, 1957c: 73, f. 49-57, 61-64 (mf; misidentified per Levi, 1969: 71).
Tidarren haemorrhoidale Levi, 1969: 71 (T from Theridion, S of Tidarren elevatum, T. fordulum, T. minor and T. texanum, all removed from S of T. fordum, rejecting Levi, 1957c: 73).
Tidarren haemorrhoidale Breene et al., 1993: 59, f. 27A-C (mf).
Tidarren haemorrhoidale Knoflach & van Harten, 2006: 1590, f. 260-265, 267-271 (mf).

Tidarren horaki Knoflach & van Harten, 2006: 1582, f. 184-185, 195, 243-246 (Df).

Tidarren konrad Knoflach & van Harten, 2006: 1540, f. 16, 136-141 (Df).

Tidarren lanceolatum Knoflach & van Harten, 2006: 1561, f. 176, 204-207 (Df).

Tidarren levii Schmidt, 1957: 283, f. 4-5 (Df).
Tidarren levii Knoflach & van Harten, 2006: 1562, f. 208-211 (f).

Theridium mixtum O. Pickard-Cambridge, 1896a: 206, pl. 24, f. 11 (Df).
Steatoda mixta F. O. Pickard-Cambridge, 1902a: 383, pl. 36, f. 8 (f).
Tidarren mixtum Chamberlin & Ivie, 1934: 9, pl. 2 (mf).
Tidarren mixtum Kraus, 1955b: 19, f. 43-44 (f; f. 45-48 see see Tidarren haemorrhoidale).
Tidarren mixtum Levi, 1957c: 72, f. 40, 46-48 (f).
Tidarren mixtum Knoflach & van Harten, 2006: 1597, f. 272-275 (f).

Tidarren obtusum Knoflach & van Harten, 2006: 1585, f. 186, 190-192, 247-258 (Dmf).

Tidarren perplexum Knoflach & van Harten, 2006: 1565, f. 177, 212-215 (Df).

Theridion scenicum Thorell, 1899: 24 (Df).
Theridion turrigerum Simon, 1900g: 418 (Df) [urn:lsid:nmbe.ch:spidersp:008754].
Theridion guineense Simon, 1907d: 257 (Df) [urn:lsid:nmbe.ch:spidersp:008405].
Tidarren scenicum Knoflach & van Harten, 2006: 1567, f. 178-180, 216-221 (f, T from Theridion, S of Theridion guineense and T. turrigerum).
Tidarren scenicum Dippenaar-Schoeman et al., 2021A: 45, 5 f. (f).

Tidarren sheba Knoflach & van Harten, 2006: 1543, f. 77, 142-153, 155 (Dmf).

Theridion sisyphoides Walckenaer, 1841: 321 (Df).
Theridion ansatum Walckenaer, 1841: 320 (Df) [urn:lsid:nmbe.ch:spidersp:062913].
Theridium fordum Keyserling, 1884a: 23, pl. 1, f. 9 (Df) [urn:lsid:nmbe.ch:spidersp:062915].
Dipoena proba O. Pickard-Cambridge, 1899a: 294, pl. 37, f. 9-10 (Dmf) [urn:lsid:nmbe.ch:spidersp:062918].
Steatoda forda F. O. Pickard-Cambridge, 1902a: 382, pl. 36, f. 7 (f).
Theridium fordum Petrunkevitch, 1930a: 194, f. 39 (f).
Tidarren fordum Chamberlin & Ivie, 1934: 5, pl. 1 (mf).
Tidarren sisyphoides Chamberlin & Ivie, 1944: 57 (removed from S of Theridion tepidariorum, rejecting Petrunkevitch, 1911: 207, S of Tidarren fordum).
Tidarren sisyphoides Levi, 1957a: 21 (S of Theridion ansatum).
Tidarren sisyphoides Levi, 1957c: 70, f. 41-45, 58-60 (mf).
Tidarren fordum Levi, 1957c: 73 (S of Tidarren elevatum, T. fordulum, Tidarren minor and T. texanum, all rejected by Levi, 1969: 71, see Tidarren haemorrhoidale, f. f. 49-57, 61-64 see T. haemorrhoidale).
Tidarren sisyphoides Levi & Levi, 1962: 44, f. 87-89 (mf).
Tidarren sisyphoides Levi, 1963a: 138 (S of Dipoena proba).
Tidarren sisyphoides Levi, 1969: 72 (S of Tidarren fordum confirmed).
Tidarren sisyphoides Levi & Randolph, 1975: 47, f. 48-50 (mf).
Tidarren sisyphoides Gruia, 1977: 159, f. 2-4 (mf).
Tidarren sisyphoides Roth, 1982: 47-9, f. 48-50 (mf).
Tidarren sisyphoides Roth, 1985: B43-9, f. 48-50 (mf).
Tidarren sisyphoides Roth, 1994: 183, f. 48, 50 (mf).
Tidarren sisyphoides Agnarsson, 2004: 601, f. 86A-G, 87A-F (mf).
Tidarren sisyphoides Knoflach & van Harten, 2006: 1599, f. 1, 5-6, 37, 266, 276-289 (mf).
Tidarren sisyphoides Jiménez et al., 2024: 199, f. 74-75, 137-139 (f).

Tidarren ubickorum Knoflach & van Harten, 2006: 1571, f. 181-182, 193, 222-225 (Df).
Tidarren ubickorum Dippenaar-Schoeman et al., 2021A: 46, 2 f. (f).

Tidarren usambara Knoflach & van Harten, 2006: 1573, f. 183, 226-229 (Df).