Last modified Mar. 30, 2000

FAMILY TRIPLOPORELLACEAE

TRIBE SELLIPORELLEAE

GENUS Neoteutloporella BASSOULLET et alii 1978

SPECIES Neoteutloporella rajkae PARENTE et CLIMACO 1999

(by M. Parente)

1. Synonymy list

1999  Neoteutloporella rajkae n. sp.- Parente & Climaco, Pl. 34, fig. 1-8; Pl. 35, fig. 1-8

2. Types

Holotype: Pl. 34, fig. 1 & 3, thin section N° AC572.7;
Isotypes : Pl. 34, fig. 2 & 4, thin section N° AC554.23; Pl. 34, fig. 5, thin section N° AC354.21; Pl. 34, fig. 6, thin section N° AC561.2; Pl. 34, fig. 7, thin section N° AC561.6; Pl. 34, fig. 8, thin section N° AC560; Pl. 35, fig. 1, thin section N° AC559.1; Pl. 35, fig. 2, thin section N° AC554.22; Pl. 35, fig. 3, thin section N° AC561.1; Pl. 35, fig. 4, thin section N° AC554.23; Pl. 35, fig. 5, thin section N° AC562.2; Pl. 35, fig. 6, thin section N° AC565.12; Pl. 35, fig. 7, thin section N° AC554.20; Pl. 35, fig. 8, thin section N° AC565.1, V. Zamparelli Collection, Dipartimento di Scienze della Terra, Università di Napoli "Federico II" (Italy)

Type locality: Mte Rotonda, E Maratea, Basilicata (Italy)

Stratum typicum: Upper Triassic, Norian

3. Diagnosis

Original diagnosis (Parente & Climaco, 1999): « Calcareous skeleton simple, articulated (undulated) with well spaced swellings consisting of thin hook-like apophyses. Primary laterals inclined upward, short and acrophore, arranged in well spaced whorls. Each primary lateral bears a tuft of 4-6 elongated secondary laterals each consisting of 3-4 segments separated by constrictions. First segment of secondary laterals acrophore; second segment acrophore to slightly trichophore, third and fourth segment slender and trichophore. Secondary laterals keep at first the same inclination as the primary laterals, then bend upward setting subvertical and finally bend downward paralleling the hook-like apophyses at the outer surface of the skeleton. Reproductive organs unknown, seemingly cladospore and located in the first or second segment of secondary laterals. »

4. Description

Original description (Parente & Climaco, 1999):
« General characters of the calcareous skeleton. The calcareous skeleton of Neoteutloporella rajkae n. sp. is articulated. Its outer surface is characterised by well spaced swellings whose maximum height, taken in the proximal portion, is about 250-350 μm. The long (800-1440 μm) portions of skeleton intervening between two subsequent swellings are bound outward by slightly concave surfaces.
The type of articulation present in Neoteutloporella rajkae n. sp. can be described as undulation, following the nomenclature of PIA (1912) and DE CASTRO (1997), because even in the most constricted parts the skeleton is rather thick. As in other species showing this type of articulation the skeleton was massive, undulation did not affect its rigidity and specimens are found as whole skeletons and not as isolated articles.
The swellings are made of thinning outward apophyses of the calcareous skeleton. These thin and fragile apophyses can be partly to almost completely obliterated by subsequent abrasion and breakage. Where completely preserved they show an hook-like shape in longitudinal and oblique sections (Pl. 34/2, 35/7) with a short and thicker proximal part directed upward, a longer and thinner median part perpendicular to the central stem axis and a very short and thin distal part bending downward. Most frequently in our material subsequent abrasion truncated the hook-like distal part so that only the proximal and median ones are preserved (Pl. 35/3, 35/4). In a few specimens abrasion went as deep as to leave only short stumps at the outer surface of the skeleton (Pl. 34/1, 35/1). The variable morphology of the apophyses is certainly a preservation artefact since different parts of the same specimen often show the whole range of shapes (Pl. 35/1, 35/4, 35/7).
The maximum outer diameter of the calcareous skeleton (D_max), taken at the distal end of the apophyses is 2080-5120 μm (3495 ± 791 μm). The corresponding maximum thickness of the skeleton (e_max) is 700-2060 μm (1315 ± 344 μm). The minimum outer diameter, taken at the constrictions of the skeleton (D_min), is 1520-4720 μm (2623 ± 818 μm). The corresponding minimum thickness of the skeleton (e_min) is 460-1860 μm (889 ± 365 μm). These values have been measured from longitudinal and oblique sections of specimens (Tab. 1). The biometric values of specimens in transversal sections vary because the section may run through a swelling or through a constriction (Tab. 2).
The longest specimens in our material are up to 2 cm long. They show that the outer diameter of the skeleton increases slightly and regularly upward (Pl. 35/4). Unfortunately the inner surface of the skeleton is not preserved in these very long specimens so that we cannot control if the diameter of the central stem is increasing too.
In well-preserved specimens of Neoteutloporella rajkae n. sp. the calcareous skeleton envelopes the laterals from their insertion point on the central stem up to their distal ends. Therefore in these specimens the inner diameter of the skeleton (d) corresponds to the diameter of the central stem. Its value is 560-1120 μm (835 ± 158 μm) (Tab. 3).
We observed many specimens and fragments of Neoteutloporella rajkae n. sp. where only the outer part of the skeleton is preserved. Their specific identification is based on the very peculiar morphology of the hook-like apophyses of the skeleton. In some specimens the inner part of the skeleton is totally missing (Pl. 35/4). In others the central stem wall is preserved and lined by a thick micritic rim but large and irregular cavities occur in the proximal and median part of the skeleton (Pl. 35/2).
The laterals. In fossil Dasycladales, shape, size and arrangement of laterals are deduced from the pores of the calcareous skeleton as observed in random sections (De Castro, 1997). In specimens of Neoteutloporella rajkae n. sp. the preservation of the pores of the skeleton is far from perfect. In many specimens the pores have been almost completely obliterated by recrystallization (Pl. 34/2, 34/3, 34/7). Very often the inner part of the calcareous skeleton is completely missing or largely destroyed by dissolution. Our conclusions on shape and arrangement of laterals are therefore largely based on a few "lucky" specimens where the pores are preserved as cement filled cavities lined by a thick micritic rim.
Neoteutloporella rajkae n. sp. is characterised by short acrophore primary laterals bearing a tuft of long and segmented trichophore secondary laterals.
The primary laterals are arranged in well spaced whorls (Pl. 34/1, 35/3 ). The distance between whorls (h) is 800-1440 μm (1123 ± 165 μm). Each whorl is made of 15-26 (21 ± 4) laterals (Tab. 3). The primary laterals are short and acrophore (Pl. 34/1 , 34/3, 35/3) and are always inclined upward (a₁=35°-65°). Their length (l₁) is 250-350 μm (296 ± 40 μm). The vertical diameter (p_1r) is 125-150 μm (148 ± 8 μm); the verticillar diameter (p_1v) is 150-200 μm (180 ± 21 μm).
Each primary lateral bears a tuft of secondary laterals. Their number per whorl is very difficult to count the number of laterals per tuft. Some longitudinal and oblique sections show that each primary bears 3-4 secondary laterals in a longitudinal plane (Pl. 34/1, 34/3, 35/5). Transversal sections show 1-2 secondary per primary lateral (Pl. 34/7). In tangential sections (or tangential parts of oblique sections), cutting through the proximal part of a tuft, the pores are so crowded that is impossibile to correlate each pore to its tuft (Pl. 35/1). Our best guess is that each primary lateral bears a tuft of 4-6 secondary laterals.
The secondary laterals of Neoteutloporella rajkae n. sp. are segmented (Pl. 4/3, 34/4, 34/6, 35/2, 35/6, 35/8). Each lateral consists of at least 3-4 segments separated by constrictions. The first segment is acrophore (Pl. 34/1, 34/2, 34/4). Its length (l_2') is 450-600 μm (525 ± 65 μm), its vertical diameter (p_2'r) is 150-175 μm (153 ± 9 μm). The second segment is more elongated, acrophore to slightly trichophore (Pl. 34/1, 34/2, 34/4,34/6, 35/6). Its length (l_2") is 400-900 μm (650 ± 250 μm); the vertical diameter (p_2"r) is 100-150 μm (113 ± 25 μm). The remaining part of the secondary lateral is long, slender and distinctly trichophore (Pl. 34/1, 34/2, 34/6, 35/3, 35/4, 35/6). Because of the poor preservation of most specimens it is difficult to state if the trichophore part of secondary laterals comprises just one very long or two shorter segments. The length of the secondary laterals from the apex of their second segment to the outer surface of the skeleton (not including the hook-like end) is 850-1500 μm (1158 ± 227 μm). The diameter of the distal end of secondary laterals (p_2min) is 50-100 μm (75 ± 19 μm).
The very peculiar shape of the tufts of secondary laterals, as seen in longitudinal sections, is due to changes of inclination of the laterals along their course (Pl. 34/1). As stated above 3-4 laterals are usually seen in a longitudinal plane cutting through the proximal part of a tuft. The first and second segment of the central lateral(s) keeps the same inclination as the primary lateral , the upper and lower laterals at first diverge (first segment) and then converge (second segment) so to set parallel to the "central" lateral(s) (Pl. 34/3). Then all the secondary laterals bend upward setting at an angle of 10°-20° while they converge (Pl. 34/1). Finally the distal part of the secondary laterals bends downward following the hook-like course of the skeleton apophyses. The radial diameter of the tuft of secondary laterals therefore reaches its maximum at the first segment and thins out markedly at the third and fourth (?) segment (Pl. 34/1). The radial diameter of the tuft at its distal end is not larg enough to accomodate 3-4 laterals in a vertical plane. Some of them are probably displaced so that only one or two thin secondary laterals per tuft are seen in longitudinal sections at the outer surface of the skeleton.
Reproductive organs. We can only suppose that Neoteutloporella rajkae n. sp. was provided with uncalcified cladospore reproductive organs seemingly located in the primary laterals or in the first or second segment of secondary laterals. »

Measurements (see above: blocks 1 & 2, longitudinal and oblique sections; block 3, transversal sections)

5. Remarks

6. Stratigraphic range

Norian (Parente & Climaco, 1999)

7. Real distribution

Italy (Parente & Climaco, 1999)

8. Paleoecology

10. Reference

PARENTE M., CLIMACO A. (1999).-
Dasycladalean green algae from the Upper Triassic of Mt. Rotonda (Verbicaro Unit, Calabria-Lucania border, Southern Italy). Facies, Erlangen, 41, p. 159-182, 7 pl. (34-40).