UDK 561.26:551.76(497.1)
Stratigrafsko značenje mezozojskih dasikladaceja s obzirom na nova taksa u Jugoslaviji*
Ivan Gušič
Biostratigrafsko značenje mezozojskih dasikladaceja razabire se iz činjenice, da je u zadnjih 15 godina u Jugoslaviji opisano preko 40 novih vrsta (sa 7 novih rodova), a od toga preko 35 iz naslaga mladih od trijasa. Tako se danas može reci da je donja kreda ono razdoblje koje se ističe po varijabilnosti oblika, a razlog tome leži barem djelomično i u činjenici da je to razdoblje kad istovremeno egzistiraju j oš oblici koji su svoj maksimum postigli u paleozoiku i trijasu, odnosno neposredno iz njih izvedeni oblici, a več se i dosta obilno javljaju visoko organizirani oblici (Triploporelleae i srodni) koji če skoro potpuno prevladati u tercijaru.
Na više primjera pokazano je da se različiti tipovi morfološke (strukturne) i fiziološke (reproduktivne i dr.) organizacije kod dasikladaceja pojavljuju rani je nego što se do nedavno smatralo, odnosno da su se pojedini dogadaji u evoluciji dasikladaceja više puta opetovali u različito vrijeme na različitim razvojnim linijama, ili, gledano s drugog stajališta, da več vrlo rano (večinom več u paleozoiku) imamo prisutne sve morfološke i strukturne oblike.
Od otvorenih problema ukazano je na neke sinonime: Pianella Ra-doičič = Salpingoporella Pia, Favoporella annulata Sokač = Diplopora annulatissima Pia, Triploporella neocomiensis Radoičič = Diplopora john-soni Praturlon, Clypeina jurassica minor Kerčmar = C. inopinata Favre = C. jurassica Favre, Cymopolia heraki Gušič = C. mayaense Johnson & Kaska, a generička pripadnost problematična je kod Oligoporella chia Herak, Teutloporella gallaeformis Radoičič, Macroporella adriatica Gušič, te Cylindroporella anici Nikler & Sokač u vezi s poimanjem rodova Cylindroporella-Heteroporella. Brojne nove vrste i rodovi koje su iz donje krede Nikšičke 2upe, Črna Gora, postavili Sokač & Nikler opet aktualiziraju pitanje da li je prikladnije usko shvačanje taksionomskih kategorija, ili nešto šire shvačanje, sa širim rasponom varijacija? Na kraju je spomenut i problem tzv. »Munieria baconica« (prema Ca-rozzi-u), koji izgleda da se počeo rješavati u dobrom smjeru.
Bibliografija obuhvača preko 100 referenci, od kojih nije moguče izdvojiti samo nekoliko najvažnijih, pa se zato ovdje ne navodi.
Stratigraphic Significance of Mesozoic Dasycladaceans with Regard to New Taxa in Yugoslavia
Ivan Gušič Abstract
Biostratigraphic significance of the Mesozoic dasycladaceans in Yugoslavia can be seen from the fact that, during the last 15 years, more than 40 new species (among which over 35 from the deposits younger than Triassic) and 7 new genera have been established. Thus it can now be said that this is the Lower Cretaceous which occupies the first place as to the richness and variability of different forms. This can be, at least partly, explained by the fact that this is the time when simultaneously exist the forms which had reached their maximum development already in the Palaeozoic and Triassic (or the forms which can be directly traced from these), and the highly organized forms (such as Triploporelleae and related forms) which will predominate in the Tertiary.
Several examples have been chosen to show that different types of morphologic (structural) and physiologic (reproductive etc.) organization in the dasycladaceans occur earlier than it has been thought until recently. Or, in other words, single events in the dasyclad evolution took place repeatedly at different times in different evolutionary lineages, or, taken from other standpoint, most morphologic and structural types are present already in the Palaeozoic.
Several taxonomic problems have been put forward. Following forms are considered synonyms: Pianella Radoičič = Salpingoporella Pia, Favo-porella annulata Sokač = Diplopora annulatissima Pia, Triploporella neo-comiensis Radoičič = Diplopora johnsoni Praturlon, Clypeina jurassica minor Kerčmar = C. inopinata Favre = C. jurassica Favre, Cymopolia heraki Gušič C. mayaense Johnson & Kaska, and the generic attribution is held problematic for Oligoporella chia Herak, Teutloporella gallaeformis Radoičič, Macroporella adriatica Gušič, and Cylindroporella anici Nikler & Sokač (owing to the relationship between the genera Cylindroporella and Heteroporella). Numerous new genera and species established by Sokač and Nikler from the Lower Cretaceous of Nikšička 2upa, Montenegro, re-actualize the question as to which characteristics are relevant in differentiating closely related genera and species, i.e. whether an extremely restrained generic and specific concept, or a more ample one, leaving more place for variations, is preferable? Finally, the problem of so-called "Munieria baconica" (after C a r o z z i) has been briefly touched upon.
A complete bibliography would include over 100 references, among which it is not possible to extract only a few, and therefore it is not listed here.