Citation: Globoconusa victori Koutsoukos 2014Rank: SpeciesType specimens: Figs. 7.1–7.10, 8.1–8.7; Holotype USNM 545313 and paratypes USNM 545314–545323, USNM 545325–545328 (in October 2011), USNM 597325, and USNM 597326 deposited at the National Museum of Natural History, Smithsonian Institution, Washington, D.C. Additional unpublished topotypes are deposited in the NMNH collections with the curatorial numbers USNM 545324, USNM 545329, USNM 597385, and USNM 597423–597427Type sample (& lithostrat): 134–136 cm ; Tamoios Member of the Ubatuba FormationType age (chronostrat): Lower Danian, Zone P1cType locality: Piston Core from Campos Basin, offshore Brazil; -22.82N; -39.07EType repository: Washington, USNM
Original Description Test small; low, compact trochospiral, tightly coiled; spiral side slightly flattened to somewhat depressed, slightly concave in outline, umbilical side inflated, and thickness , ⅔ of the diameter. Last whorl composed of 3–3½ globular chambers increasing rapidly in size; ultimate chamber is characteristically highly inflated (globular), commonly occupying from ½–⅔ of test size (~40–60%). Equatorial outline is typically trilobate. Axial periphery broadly rounded. Sutures are straight to slightly curved, depressed on umbilical side, and nearly flush/ indistinct (in the early ontogenetic stage) to slightly depressed on the spiral side. Primary aperture a very low, elongate arch or low-arched slit, extraumbilical-umbilical in position. Test microperforate, pores widely dispersed, with a distinct hispid/pustulose surface, covered by scattered to abundant blunt to more commonly sharp-pointed small pustules (enlarged view in Fig. 7.1b). Size: Holotype (USNM 545313; Fig. 7.1): maximum diameter 121 µm, thickness 87 µm, proloculus indistinct; paratypes: maximum diameter 120–180 µm (averaging 144 µm), thickness 88–125 µm (averaging 108 µm). Etymology: Named after my son Victor de Souza Koutsoukos, who accompanied me during a research period (1986–1990) in Plymouth, U.K. Extra details from original publication Synonymy:
Globigerina kozlowskii Brotzen & Pozaryska, 1961, p. 162, pl. 1, figs. 1, 2?, 7, 8 (ex interc.?).
Globoconusa tripartita Morozova et al., 1967, pl. 5, figs. 6a–c (paratype; ex interc.).
Globastica daubjergensis (Brönnimann). Blow, 1979, p. 1235, pl. 256, fig. 4 (ex interc.?).
Globoconusa daubjergensis (Brönnimann). Olsson et al., 1999, pl. 64, figs. 5?, 6 (ex interc.).
Remarks. The species is characterized by its small trilobate form with a distinctive test surface. It is distinguished from its ancestral species, Globoconusa daubjergensis, in having a compact, trilobate form with a flattened to somewhat depressed spiral side, rather than a high trochospire; a highly inflated ultimate chamber occupying from ½–_ of test size; and a distinct extra-umbilical-umbilical (rather than umbilical) aperture. Intermediate specimens occur with overall similar trilobate morphology, but with a slightly higher spire and an aperture varying from more extraumbilical and slit-like (see Olsson et al., 1999, pl. 64, fig. 6) to slightly extraumbical but arched, close to Gl. daubjergensis (Fig. 8.8; see also Morozova et al., 1967, pl. 5, figs. 6a–c).
Phylogenetic relationships. The species evolved from Gl. daubjergensis (Brönnimann) within Zone P1c through the development of a more compact trilobate test with a much larger highly inflated last chamber, and by the sharp decrease of spiral height to produce a flattened or somewhat depressed profile.
Stratigraphic range. Zone P1c (lower Danian; Fig. 4). The total range is unknown because the core is short and at its base Zone P1c unconformably overlies Zone P1a sediments.
Geographic distribution. This initial report of Gl. victori n. sp. in a deep-water core implies a preference for tropical to subtropical conditions, but this requires confirmation from additional sites.
Stable isotope paleobiology. Currently unrecorded. Editors' Notes
Koutsoukos, E. (2014). Phenotypic plasticity, speciation, and phylogeny in Early Danian planktic foraminifera. Journal of Foraminiferal Research. 44: 109-142. gs
Globoconusa victori compiled by the pforams@mikrotax project teamviewed: 29-11-2022