Evolution of the fusulinid Depratina in the Bashkirian–Moscovian interval

Fusulines From the Bashkirian/Moscovian Transition in the Carboniferous of the Cantabrian Zone (Nw Spain)

“…This interval is only clearly represented in the Santo Firme section. There, the Pseudostaffella species yielded by samples SF-2 and SF-3 (lower part of the lower interval), occur along with primitive subrhombic Profusulinella and allow us to correlate these strata with the Ozawainella pararhomboidalis-Pseudostaffella gorskyi Zone of the South Urals (Kulagina, 2009), which is Tashastian in age.…”

“…A valuable attempt to clarify the relationships of the early profusulinellids was made by Kulagina (2008Kulagina ( , 2009), who considered Staffellaeformes as having given rise in the late Bashkirian to two branches that differ considerably. One of these branches would give rise to Depratina and the other to Profusulinella.…”

“…One of these branches would give rise to Depratina and the other to Profusulinella. The genus "Ovatella" is not discussed by Kulagina (2009), but one may infer that species of the P. ovata group are included in Profusulinella since an occurrence of Profusulinella subovata is indicated in her figure 3. Van Ginkel (1987), analyzing a large collection of P. sitteri specimens, pointed out that this last species is as close to P. subovata as to P. prisca (p. 219, fig.…”

“…Further east, in the Urals, marine strata of Vereian age rest on the marine Bashkirian stratotype. In the midand southern Urals, fusulines around the Bashkirian/ Moscovian boundary are known from several sections (Sinitsyna & Sinitsyn, 1987;Ivanova, 2000Ivanova, , 2008Kulagina, 2008Kulagina, , 2009Kulagina et al, 2009). However, a break between the Bashkirian and the Moscovian could exist in some or all these areas (Ektova, 1969), this break being most conspicuous in the Moscow Basin.…”

“…In areas such as the South Urals, where marine strata exist below the Aljutovella aljutovica-Schubertella pauciseptata Zone, an older interval may also contain fusulines of Moscovian appearance (Kulagina, 2008(Kulagina, , 2009). This author distinguished the Depratina prisca Zone just below the Aljutovella aljutovica Zone, and assigned it to the lowermost Solontsian horizon, at the base of the Moscovian in South Urals.…”