Brissopsis Ottnangensis HOERNES, 1875

Brissopsis Ottnangensis HOERNES, 1875

sides of the pores facing each other; interporal area is crossed six slit-shaped unipores with an extensive attachment area in by a narrow ridge of stereom, which links the two pores). In each ambulacrum (Fig. 80.A). the adapical third of the anterior poriferous zones of the ante- Interambulacra: Aborally the interambulacra are strongly in- rior paired petals the pores are distinctly reduced in size. In the flated between the petals. Aboral tuberculation is very dense posterior poriferous zones and in both poriferous of the poste- and homogenous. The tubercles become larger towards the rior paired petals this is not the case (Fig. 78.D). The posterior ambitus and on the oral side. On the plastron the tubercles are paired petals are usually between 70 and 85 % of the length of arranged in a fan-shaped pattern, radiating from an elevation the anterior ones. In juveniles and sub-adult specimens (TL ~ in the posterior part of the plastron. The plastron belongs to 15 mm) they can be even shorter (~ 65 %). Anterior paired the holamphisternous type (Figs. 79.A-D) and forms a strong petals extending about 60 to 70 % of the corresponding test keel along its central suture. The labrum is short, T-shaped, radius, while the posterior paired petals extend about 50 %. slightly wider than long and projects slightly into the peri- The anterior paired petals diverge at an angle of about 85 to stome. Usually it does not extend beyond the first ambulacral 115°, the posterior ones at about 50 to 75º. Neither, anterior plate of the adjacent ambulacra (Fig. 80.A). In a single speci- nor posterior petals are confluent (Figs. 78.C-D). men, however, it extends to the second ambulacral plate (Fig. Ambulacra II, III and IV are sparsely tuberculated ambitally 80.B). According to TURNER & NORLUND (1988) this atypical con- and bear vertically elongated, slit-shaped unipores. On the oral dition may occur in Brissopsis species which are usually charac- side ambulacra I and V form broad, naked peri-plastronal areas terised by a labrum that does not extend beyond the first am- bearing few secondary and miliary tubercles. The pores in bulacral plates. these areas are antero-posteriorly elongated, slit-shaped uni- Plastron width is relatively variable. In the material from the pores. Five ambulacral plates extend into the subanal fasciole, type-locality it increases during ontogeny due to allometric bearing four enlarged pores on each side (Fig. 80.C-D). Ad- growth. In the smallest specimens (TL ~ 15 mm) it ranges from orally all ambulacra form small phyllodes consisting of five to 33 to 37 % of TW and increases to 41 % in the largest speci- Figure 80: Brissopsis ottnangensis HOERNES, 1875: labrum shape, typical condition (A: Badenian, Devínska Nová Ves, Slovak Republic, SNM z24181), rare condition with labrum extending to 2nd ambulacral plate on each side (B: Badenian, Devínska Nová Ves, Slovak Republic, SNM z24180), anal plating (C: Ottnangian, Ottnang, OÖ, Austria, NHMW 1997z0178/0520; D: Badenian, Retznei, Styria, Austria, NHMW 2004z0098/0002). Interambulacra shaded, poorly visible sutures omitted or stippled, subanal fasciole dotted. Numbering of anal and preanal plates follows the Lovénian system; Abbreviations: ep = episternal plate, pa = preanal plate, an = anal plate. Figure 81: Brissopsis ottnangensis HOERNES, 1875: peripetalous fasciole shape (A: Badenian, Devínska Nová Ves, Slovak Republic, SNM z24179; B: Badenian, Devínska Nová Ves, Slovak Republic, SNM z24182; C-D: A: Badenian, Kalksburg, Vienna, Austria, NHMW 1981/55/12). 172 SYSTEMATIC PART SYSTEMATIC PART 173 mens. In specimens from the Badenian of Devínska Nová Ves a specimens), more circular outline (TW ranging from 96 to 103 markedly narrower plastron (~ 30 % of TW in 30 mm speci- % TL), and less strongly indented peripetalous fasciole in inter- mens) is observed. ambulacra 1 and 4. Unfortunately no specimens have been The shape and number of the preanal and anal plates is available for direct comparison. It is also unclear how the Bur- similar to the condition observed in B. atlantica by TURNER & digalian specimens of B. duciei look like, as all illustrations NORLUND (1988: fig. 3 A), both in material from the type local- depict specimens from the Messinian Upper Coralline Lime- ity Ottnang (Fig. 80.C) and in younger (Badenian) specimens stone. In any case the two species seem to be closely related (Fig. 80.D). There is only one pair of preanal plates (plates and further investigations involving material from the Burdi- 5.a.4, 5.b.4), and the first anal plates (5.a.5, 5.b.5) are dis- galian of Malta are necessary to see if the two forms might be tinctly elongated vertically, tapering and form only a narrow end-members of a species with broader intraspecific varia- portion of the periproctal margin. tion. Peristome: The peristome is situated anteriorly on the oral side Brissopsis specimens from the Badenian of Austria differ of the test, about 15 to 25 % of TL from the anterior margin. from B. ottnangensis from the type-area by its slightly more It is kidney-shaped and measures 2.5 vs. 7 mm in a 40 mm TL diverging anterior (~ 90-115°) and slightly less diverging pos- specimen. The labrum is only slightly projecting. terior (50-60°) paired petals. Yet these features show consider- Periproct: The periproct lies high on the posterior face of the able variation in the “population” from the type-locality too test. It is nearly circular in shape but poorly preserved in most and the overlap is large. Moreover, the different preservation available specimens. In some specimens, especially in smaller hampers comparison and distorts metric features (Ottnangian ones it is partially visible in aboral view due to the obliquely specimens come from pelitic sediments, are deformed and usu- truncated posterior end. ally lack the original test; Badenian specimens, in contrast come Fascioles: Both peripetalous and subanal fascioles are present. from carbonates and retain the original shell). The key features They belong to the orthofasciole type (sensu NÉRAUDEAU & al. used for the differentiation of extant Brissopsis species (petal 1998b). The peripetalous fasciole is indented between the an- shape and structure, labrum shape, number and shape of the terior and posterior paired petals (Figs. 81.A-C) and has a dis- preanal and anal plates, shape of the fascioles and number of tinct kink in interambulacra 2 and 3 (Fig. 81.D). The subanal ambulacral plates extending into the subanal fasciole) are iden- fasciole is kidney shaped (Fig. 80.D). tical in the material from both time slices. Thus they are treated as conspecific here. Differential diagnosis: VADÁSZ (1915) identified this species with B. consobrinus Brissopsis crescenticus WRIGHT, 1855 from the Early Miocene LAMBERT, 1909 from the “Helvétien” (? Middle Miocene) of of Malta differs from this species by its confluent petals, with Sardinia, which is indeed extremely similar to the present tax- distinctly laterally flexed petal tips, much less strongly diverg- on. Without knowledge on the plating pattern, width of the ing posterior petals, and more elongated outline [based on plastron and other features not mentioned by LAMBERT an at- topotypic material collected from the Lower Globigerina Lime- tribution to that species can only be tentative. stone in Malta; see also CHALLIS, 1980; the material from the Several of the Brissopsis species and subspecies of BOTTO- Burdigalian of the Rhône Basin attributed to B. crescenticus by MICA (1896) are similar to B. ottnangensis. All of them are, PHILIPPE (1998) is not typical of that species, if at all conspeci- however, based on internal moulds and plating patterns, plas- fic]. tron structure and shape of the fascioles are unknown. Because The Pliocene to extant B. atlantica MORTENSEN, 1907, which is of this lack of information it is impossible to judge their relation the descendant of B. crescenticus according to MORTENSEN to B. ottnangensis without re-examination of BOTTO-MICA’s (1951), likewise differs by its confluent posterior petals and material. laterally flexed anterior petals (among other features; compare MORTENSEN, 1913; BORGHI, 1997; LACOUR & NÉRAUDEAU, 2000). Occurrence: The extant B. elongata MORTENSEN, 1907 from the Caribbean and the South Atlantic differs by its confluent posterior petals, Austria: Eggenburgian (Early Burdigalian) to Late Badenian different arrangement of the anal and preanal plates and (Early Serravallian) straight labrum margin (compare TURNER & NORLUND, 1988). Molasse Zone: Antiesenhofen, near Schärding/Inn, OÖ The Late Miocene to extant species Brissopsis lyrifera ([NHMW]); borehole Eisenhub 2, OÖ (SCHAFFER & GRILL, (FORBES, 1841) is very similar to B. ottnangensis and the latter 1951); Großwiesenhardt, near St. Marienkirchen, OÖ species certainly belongs into the Brissopsis lyrifera – group as ([NHMW]); Haller Schlier, Pfarrkirchen, OÖ ([NHMW]); identified and characterised by LACOUR & NÉRAUDEAU (2000). Mechters, near St. Pölten, NÖ (ABEL, 1904); Ort, near Bad Main differences to B. lyrifera are the shape of the individual Füssing, OÖ (WEIDLINGER, 2003); Ottnang, OÖ (HOERNES, petals (more lanceolate in B. lyrifera, wider and more lobate in 1875a, b; KITTL, 1886; COMMENDA, 1900; TOULA, 1914; VEIT, B. ottnangensis), fasciole shape and overall test shape [extant 1943; SCHAFFER & GRILL, 1951; SIEBER, 1956; PAPP & THENIUS in B. lyrifera are more elongated (TW of ~ 85-91% TL) than B. KÜHN, 1962; STOJASPAL, 1975; RUPP et al., 1991; [GBA]; ottnangensis] (compare data and illustrations found in [NHMW]); Pichl, WNW of Wels, OÖ (SUESS, 1891); Pielach MORTENSEN, 1951; BORGHI, 1997; LACOUR & NÉRAUDEAU, 2000). river, south of Völlerndorf, NÖ ([NHMW]); Platt, near The Cuban species B. aguayoi SÁNCHEZ ROIG, 1952 from the Zellerndorf, NÖ (SIEBER, 1935; KROH, 2003b); St. Pölten, NÖ Oligocene to Miocene and B. jimenoi COTTEAU, 1875 from the (ABEL, 1904; [NHMW]); Schlierfazies der Innviertler Serie, Miocene differ by their strongly confluent posterior and later- OÖ (TOLLMANN, 1985) ally flexed anterior petals (compare KIER, 1984).

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