Taxonomy and ontogeny of the Lituitida (Cephalopoda) from Orthoceratite Limestone erratics (Middle Ordovician)
Author
Aubrechtová, Martina
CAF4231-8787-4051-8D76-F983332517EE
Institute of Geology and Palaeontology, Faculty of Science, Charles University Prague, Albertov 6, Prague, 12843, Czech Republic. & Institute of Geology, Czech Academy of Sciences, Rozvojová 269, Prague, 16500, Czech Republic.
aubrech1@natur.cuni.cz,aubrechtova@gli.cas.cz
Author
Korn, Dieter
286CA4F3-7EBC-4AEF-A66A-B2508D001367
Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstrasse 43, 10115 Berlin, Germany.
dieter.korn@mfn.berlin
text
European Journal of Taxonomy
2022
2022-03-08
799
1
1
108
http://dx.doi.org/10.5852/ejt.2022.799.1681
journal article
20271
10.5852/ejt.2022.799.1681
f53d5465-7162-45d6-892b-dfc0b8d99789
2118-9773
6341270
F52DBAB0-38C7-400F-9BA1-E2D8E6B19E7E
Lituites bottkei
sp. nov.
urn:lsid:zoobank.org:act:
E0CCF553-04EB-4E2C-9E3F-6653ABF2432A
Figs 54B
,
56–57
,
Tables 9–10
Diagnosis
Species of the genus
Lituites
with coiled part ca
26 mm
in diameter; coiling open, the last whorl approaches preceding whorls just before uncoiling. Uncoiled part moderately curved, expansion angle 6–7°. Shell ornament with growth lines, transverse lirae and annuli; irregularly developed in thickness and spacing. Ornament elements biconvex in the coiled conch. Ventral sinus moderately deep, lateral sinus wide and shallow, dorsolateral sinus shallow, dorsal projection low.
Etymology
After the late Werner Bottke (1943–2020), the collector of the
holotype
.
Type material
Holotype
SWEDEN
•
Island of Öland
,
Gärdslösa
;
Middle Ordovician
;
Bottke
Coll.;
MB.C.29651
(illustrated in
Fig. 54B
).
Paratype
POLAND
•
West Pomerania
,
Ustronie Morskie
(former Henkengahen);
Ordovician
;
Müldner?
Coll.;
MB.C.30536
.
Description
Holotype
MB.C.29651 (
Fig. 54B
) consists of the coiled part (dm =
26 mm
; coiling is open with the whorls not in contact; only the last whorl nearly touches the preceding just before uncoiling;
Fig. 56
) and the moderately curved backcoiled and straight parts (length =
300 mm
; wh =
42 mm
; EA ~ 6°). The ornament is best preserved in the penultimate whorl. It is here composed of various successive elements including shallow, rounded annuli, irregularly spaced growth lines and raised lirae. In the backcoiled part, very weak annuli are developed with irregular distances (between 0.5 and 1.0 mm apart); they are particularly well-visible in the ventrolateral area. Lirae (
0.1–0.3 mm
apart) cover the annuli and their interspaces. They are slightly coarser on the ridges of annuli. The ornament elements become progressively more prominent until the beginning of the straight part (wh ~
17 mm
,
Fig. 57
), where the shell bears traces of healed injuries (
Fig. 6A
). For another
21 mm
of conch length following the position of the damage, the shell ornament is composed of widely spaced annuli (ca
4 mm
apart) and lirae (
0.6 mm
apart). After that, the annuli become weaker, less regularly developed; at the end of the straight part of the conch, the annuli attain a maximum distance of ca
3 mm
. The ornament elements extend with moderately deep ventral sinus, wide and shallow lateral sinus, shallow dorsolateral sinus and low dorsal projection. The chamber length can be measured only locally (CLR between 0.36 and 0.42).
Fig. 56.
Lituites bottkei
sp. nov.
A
. Outline of coiled conch part of holotype MB.C.29651.
B–E
. Conch proportions and coiling rates of holotype MB.C.29651. Scale bar units = 1 mm.
Fig. 57.
Lituites bottkei
sp. nov.
A
. Lirae of holotype MB.C.29651 (Bottke Coll.) from Gärdslösa (Island of Öland, Sweden), at wh = 32 mm.
B–C
. Ontogenetic development of lirae distance (in mm) and lirae distance/whorl height of holotype MB.C.29651. Blue dots = individual measurements, black lines = three data point averaged values. Scale bar units = 1 mm.
Remarks
Lituites bottkei
sp. nov.
differs from
L. lituus
in the loosely coiled part of the conch and in the ornament, which is generally finer with biconvex course in the coiled conch.
Lituites bottkei
sp. nov.
differs from
L. perfectus
in regular coiling (i.e., the whorls are not eccentric) and greater expansion angle (6° vs 1–3°) of the uncoiled part.
Specimen MB.T.4492.52 is a nearly complete body chamber with several chambers of the phragmocone, which corresponds to the dimensions and expansion angle of
L. bottkei
sp. nov.
However, the ornament is coarser (annuli up to
4 mm
apart) and the specimen is therefore classified as
Lituites
cf.
bottkei
.
Geographic and stratigraphic occurrence
Sweden
(in situ) and
Poland
(in erratics within Pleistocene gravels); Middle Ordovician.