liik

Planolites montanus Richter, 1937

Taksoni kirjeldused

Stachacz, 2012b

Diagnosis. Relatively small, curved to contorted Planolites, less than 5 mm in diameter (Pember ton and Frey, 1982; Fillion and
Pickerill, 1990).

Christopher et al., 1994

Remark.P. beverleyensis a relatively large unornamented form, while P. montanus is relatively small (less than 5 mm in diameter) and unornamented (Pemberton and Frey, 1982; Fillion and Pickerill, 1990).

Hofmann et al., 2012

Description.—Subcylindrical to cylindrical, horizontal to inclined vermiform structures with smooth surface, predominantly preserved as full-reliefs within heterolithic facies (Fig. 7.8). Burrow width is 1 to 8 mm but is most commonly 3 to 5 mm. Overlap among specimens is common. Fill differs from host rockin being typically finer-grained.

Remarks.—Planolites montanus is distinguished from other ichnospecies of Planolites by its tortuous course with horizontal and inclined segments, penetrative nature, and lack of ornametation (Pemberton and Frey, 1982).

Pemberton & Frey, 1982

Irregularly cylindrical, sinuous, undulose and meandrous small burrows exibiting no obvious pattern other than a general dendency toward horizontal development. Burrow diameters may remain more or less constant but typically exhibit slight to pronounced small-scale variations. True branching is relatively rare, crossovers, interpenetrations and reburrowed segments may be abundant to profuse. Many specimens are highly undullose; inthese only short segments coincide with any given plane. Horizontal erosional truncation of vertically or obliquely oriented segments may give the appearance of knobby or "punctate" bedding surfaces. Burrow fills tend to consist of cleaner, better sorted sediments than the host matrix. Preserved an endichna, hypichnal ridges and epichnal grooves.

Lima & Netto, 2012

Horizontal or slightly inclined, rectilinear to slightly curved burrows of flattened to cylindrical section. No branching is observed and overlapping is rare. Burrow with smooth margins, without lining. Burrow fill differs from the host rock by having coarser grains and, apparently, being devoided of organic matter. Average burrow diameter 3.2 mm, the smallest measuring 1.18 mm and the biggest 7.41 mm. Preservation in positive hyporelief.

Orłowski & Źylińska, 1996

Horizontal burrows, straight or gently curved, with smooth walls, oval in cross section, diameter from 1 to 5 mm. They were produced close to the surface of the clay and follow very complex surfaces modelled by other burrowers. The burrow was apparently open to the surface along its whole length and is completely filled with sand from the overlying bed. Convex epireliefs.

Sünonüümika
1937     Planolites montanus sp. nov. — Richter , lk. 151, joon. text fig. 1-5
1962     Planolites montanus — Häntzschel , joon. text fig. 129.7
1963     Planolites montanus — Seilacher , lk. 84 , joon. text fig. 1
1970     Planolites ballandus sp. nov. — Webby , lk. 95, joon. 14A–C
1975     Planolites montanus Richter, 1937 — Alpert , lk. 513, joon. 2:3,6
1975     non Planolites montanus Richter, 1937 — Alpert , joon. 2:3,6
1982     Planolites montanus Richter, 1937 — Pemberton & Frey , lk. 869-870, joon. 2:4,7; 3:9
1984     Planolites montanus Richter, 1937 — Pickerill et al. , lk. 423, joon. 6A
1984     Planolites montanus Richter, 1937 — Howard & Frey , lk. 207, joon. 15
1985     Planolites montanus Richter, 1937 — Frey & Howard , lk. 386, joon. 5.10; 5.16; 10.8; 19.4
Valik taksonit käsitlevast teaduskirjandusest
Toom, U., Vinn, O., Hints, O. 2019. Ordovician and Silurian ichnofossils from carbonate facies in Estonia: A collection-based review. Palaeoworld 28, 1-2, 123-144. DOI:10.1016/j.palwor.2018.07.001
Landing, E., Peng, S., Babcock, L. E., Geyer, G., Moczydlowska-Vidal, M. 2007. Global standard names for the Lowermost Cambrian Series and Stage. Episodes 30, 4, 287-289. DOI:10.18814/epiiugs/2007/v30i4/004
Knaust, D. 2004. Cambro-Ordovician trace fossils from the SW-Norwegian Caledonides. Geological Journal 39, 1, 1-24. DOI:10.1002/gj.941
Orłowski, S., Żylińska, A. 1996. Non-arthropod burrows from the Middle and Late Cambrian of the Holy Cross Mountains, Poland. Acta Palaeontologica Polonica 41, 4, 385-409.
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