Medullopteris dżosiufucus sp. n. i jego zasięg stratygraficzny

Abstract

Podano diagnozę oraz omówiono szerzej nowy gatunek rośliny karbońskiej Medullopteris dżosiufucus sp. n. z Górnośląskiego Zagłębia Węglowego, kreowany przez Dźo Siu-Fu w niepublikowanej rozprawie doktorskiej jako Dicksonites sinopolonicus. Nowe znaleziska tej rośliny pozwalają na poprawne sformułowanie jej diagnozy i opisu oraz sprecyzowanie zasięgu stratygraficznego tego gatunku. MEDULLOPTERIS DŻOSIUFUCUS SP. N. AND ITS STRATIGRAPHIC RANGEThe paper presents diagnosis and discussion of new species of Carboniferous plants from the Upper Silesia Coal Basin, Medusopteris dżosiufucus sp. n. This species was described for the first time in 1962 by Dżo Siu-Fu, Chinese scholarship holder of the Academy of Mining and Metallurgy in Cracow, in his D. Sc. thesis entitled “Flora and microflora of the Westphalian C and the lowermost Westphalian D of the Jaworzno-Libiqdz area and its stratigraphic value”. The thesis was, unfortunately, not published and despite of marked scientific value of the material, it should be completely rewritten before publication nowadays.Acorrding to the Arrticle no.11a of the International Code of Zoological Nomenclature (1963), this species is invalid as its description was not published.Detailed paleobotanic studies carried out in the Upper Silesia Coal Basin and especially southern limb of the, Main Basin by the Geological Institute in 1961–1975, made it possible to precise stratigraphic ranges of several species of Carboniferous plants including the new species Medullopteris dżosiufucus and to give appropriate diagnosis and description of this interesting plant on the basis of the specimens from the Dżo Siu-Fu and present author's collections. Medullopteris dżosiufucus sp. n.(Tables I–IV)1962 Dicksonites sinopotonicus sp. n.; Dżo Siu-Fu (manuscript), p. 61–68, Table XI, figs. 1–2;Table XII, figs. 1­–2; Table XIII, XIV, XVI, figs. 1–2; Table XLIII, fig. 1; Table XLVIII.H o l o t y p u s: Table I, fig. 2; specimen no. 560 from the Dżo Siu-Fu collection, figured in manuscript of this author (1962) in Table XI, fig. 2; Arch. of the Rock Coal Deposit Laboratory of the Academy of Mining and Metallurgy in Cracow.T o p o p a r a t y p u s: Table II, fig. 3; Table Ill, figs. 4, 5 ­– specimens from the Dżo Siu-Fu collection; Table IV, fig. 8 - specimen from the, collection no. 6 of the Arch. Of the Geological Institute in Sosnowiec.A s y n c h r o n p a r a t y p u s: Table IV, figs. 6, 7 – specimens from the collection no. 122 from the Arch. of the Geological Institute in Sosnowiec.L o c u s  t y p i c u s: Jaworzno mine in the Upper Silesia Coal BasinS t r a t u m  t y p i c u m: Top of the seam no. 206 – Chełm beds – Westphalian C.De r i v a t i o  n o m i n i s: In honour of Dżo Siu-Fu who proposed the species Dicksonites sinopotonicus.D i a g n o s i s : The species of the genus Dicksonites with, small, circular to slightly elongate leaves 2–3 mm long and 1.5–2 mm wide, strongly concave, closely spaced, seated with whole base on the last-order axes to which they are set perpendicular or sometimes at acute angle.D e s c r i p t i o n. Final leaves of feather are rounded, somewhat larger than the remaining ones and often connected with those situated beneath them. Number of leaves in feather ranges from 5 to 9. Innervation of leaf is feather-like, usually invisible, obscure in thick leaf blade. Lower-order axes thin, fine and smooth. Higher-order a.xes longitudinally striated, covered with fine points after falling down trichomes.These plants ructify in the way typical of seminal ferns of the type Leptotesta grand eurii Laubiere.O c c u r r e n c e. The new specimens of Medullopteris dżosiufucus sp. n. are derived from the Góra IG 25 borehole (depth of 1161.0 and 1161.4 m) in southern part of the Central Basin of the Upper Silesia Coal Basin. The identification of coal seams (A. Kotas, W. Malczyk, 1966) showed that these specimens were found above the top of the seam no. 301 and slightly higher. The bulk of specimens are derived from the seams no. 210, 207 and 203 of the Bierut mine at Jaworzno in the Jaworzno region (south-eastern part of the Upper Silesia Coal Basin). The largest concentration of these plants was found in the seam no. 206 in that mine. Up to the present, these plants were found neither above the seam no. 200 nor below the seam no. 301. It follows that their stratigraphic range comprises the Łaziska and CheŁm beds corresponding to the Westphalian Band C.In proposing the change of generic name of this interesting endemic species there was taken into account the suggestion made by A. N. Krysthofovich and E. O. Novik (E. O. Novik, 1947). It seems justified to make a distinction between these undoubtedly seminal plants and proper ferns to which belong Recent dicksonids and to which the specimens studied were previously assigned.