Balmeisporites (Cookson and Dettmann, 1958) Dettmann, 1995

Santamarina, Patricio E., Barreda, Viviana D., Iglesias, Ari & Varela, Augusto N., 2018, Salvinialean megaspores in the Late Cretaceous of southern Patagonia, Argentina, Acta Palaeontologica Polonica 63 (3), pp. 607-616 : 612

publication ID	https://doi.org/ 10.4202/app.00491.2018
persistent identifier	https://treatment.plazi.org/id/870AF07D-FFE9-FFFF-FF9E-3C127262F994
treatment provided by	Felipe
scientific name	Balmeisporites
status

Treatment

Balmeisporites cf. B. holodictyus Cookson and Dettmann, 1958

Fig. 4 View Fig .

1958 Balmeisporites holodictyus sp. nov.; Cookson and Dettmann 1958: 42, pl. 2: 1–6, text-fig. 3.

Material. — 32 specimens measured. MPM-Pb-18907a ( J53 /3, H32 /4, K49 /1, Q49 /1, F39 ,D28/2, C33 /3, C30 /2, B40 /2, H32 /4, R33 ); MPM-Pb-18907b ( Z33 /4, W39 /4, U49 /2, J37 /1, C38 /2, E36 /2); MPM-Pb-18907 SEM stub 1 (5 specimens); MPM- Pb-18955a ( M35 /3, W43 , Y44 /2, Y34 /3); MPM-Pb-18955b V44 /3, J52 /1, N42 /3); MPM-Pb-18955c ( G25 /1); MPM-Pb- 18955d ( Z45 , H25 /1). Cenomanian of Patagonia , Argentina. Cerro Waring and Estancia Mata Amarilla localities, Mata Amarilla Formation .

Description. —Trilete megaspore with round to elliptical body. Laesurae with membranous, highly elevated lips ( Fig. 4A, B View Fig ). Lips finely granulated ( Fig. 4C View Fig ). Megaspore surface irregularly reticulate. Lumina polygonal to irregular in shape, larger near the equator ( Fig. 4A, B View Fig ), sculpture inside lumina scabrated. Muri of the reticulum narrow and low ( Fig. 4B View Fig ).

Dimensions. —Total length (body and lips) 125–197 μm, body diameter 90–142.9 μm, lumina diameter 7–20 μm, reticulum wall thickness 1–3.5 μm, length of lips 36–45 μm, width of lips 80–136 μm.

Remarks. —The Patagonian specimens broadly fit with the general diagnosis of B. holodictyus ( Cookson and Dettmann 1958; Dettmann 1995) but differ in lacking the three winglike outgrowths in each radial equatorial region. Some specimens show variations in the development of the reticulum

Fig. 4D, E View Fig ), a feature also reported for specimens from the Aptian–Albian of Australia ( Tosolini et al. 2002). Bearing in mind that we only recovered few poorly preserved specimens, we temporarily retain these megaspores within B. cf. B. holodictyus ( Fig. 4D, E View Fig ), although we cannot rule out that they belong to a different species. This species has been widely reported from the Barremian to Danian around the globe (Dettmann 1995).