<BGSOUND SRC="http://www.graptolite.net/HoraMamtera.mid" LOOP=INFINITE>
Rhabdopleura kozlowskii Kulicki, 1969
GRAPTOLITHOIDEA: Order Rhabdopleuroidea, Family Rhabdopleuridae
Diagnosis. - "Zooidal and stolonal tubes similar in size to those in Rh. normani. Fuselli of stolonal tubes much more frequently arcuate than those in Rh. vistulae, Rh. eocaenica and Rh. normani. In transverse section, stolons semicircular as in Rh. normani. Peduncular stolons short and provided with 1-3 diaphragms." From: Kulicki 1969, p. 539.
Occurence. - Jurassic of Poland (Callovian and Bathonian).
Remarks. - Remains of Rh. kozlowskii were separated by etching from a calcareous concretion, about 30 kg in general weight, found in black Callovian clays in a clay pit Lapiguz in Lukow about 100 km south-east of Warsaw, Poland. Named in honour of Professor Roman Kozłowski, a famous investigator of fossil hemichordates.
       This species, according to some researchers, is the oldest known representative of the genus
Rhabdopleura Allman.
SEM micrographs of Rhabdopleura kozlowskii from Callovian (Jurassic), Lapiguz clay pit, Lukow (Poland). A. Fragment of a zooidal tube. B. Fissure in the periderm; arrow indicates a presumably bunch of cortical fibrils. C. Unconformity between two presumably bunches of cortical fibrils on the surface of a sterile bud cyst. Note a striking similarity to cortical bandages in graptolites! From Mierzejewski & Kulicki, 2001.
Rhabdopleura kozlowskii. Diagrams of the different stolons and diaphragms observed.
From Kulicki, 1969.
References:

Kulicki, C. 1969. The discovery of Rhabdopleura (Pterobranchia) in the Jurassic of Poland. - Acta Palaeontologica Polonica 14, 4, 537-551.
Kulicki, C. 1971. New observations on
Rhabdopleura kozlowskii (Pterobranchia) in the Jurassic of Poland. - Acta Palaeontologica Polonica 16, 3, 415-429.
Mierzejewski, P. and Kulicki, C. 2001. Graptolite-like fibril pattern in the fusellar tissue of Palaeozoic rhabdopleurid pterobranchs. - Acta Palaeontologica Polonica 46, 3, 349-366.
Graptolite Net | Graptolites & Graptoliters | Rhabdopleuroidea | Cephalodiscoidea | Crustoidea | Camaroidea | Tuboidea
Graptolite Net
is edited and periodically updated by
Piotr Mierzejewski, the Count of Calmont
& Countess Maja Korwin-Kossakowska
since 2002
Portal of Graptolites and Pterobranchs sponsored by Artistic Embroidery Sztandary Flags Fahnen
updated July 7, 2005