◄ Carnets Geol. 13 (L07) ►
Contents
[1. Introduction] [2. New data and discussion]
[3. Systematics]
[4. Conclusion] and ...
[Bibliographic references]
Department of Ecology and Evolutionary Biology, The
University of Kansas, 1200 Sunnyside Avenue, Lawrence, Kansas 66045 (USA)
Manuscript online since December 25, 2013
[Editor: Michel ;
copy editor: Bruno ; language editor: Stephen
]
First ascribed to the Triploporellacean genus Dissocladella ( in & , 1936), the species D. hauteriviana in et al., 1999, was supposedly characterized by a thallus bearing whorls of laterals each consisting of a stumpy primary with a tuft of four slim secondaries at its top. A restudy of the laterals proves that they split, not only once, but several times, and stepwisely decrease in diameter. The species is re-ascribed to the Family Thyrsoporellaceae in a new combination to the genus Deloffrella & , 1987. Its known stratigraphic range is rather short (Late Valanginian-earliest Barremian). In addition, it disappears earlier than its companion Polyphysacean alga, i.e., Clypeina paucicalcarea (, 1970), and its geographical distribution is broader, which makes it a good index fossil for lower Urgonian carbonate platform series.
Calcareous fossil algae; Dasycladales; Thyrsoporellaceae; Deloffrella; Hauterivian; lowermost Barremian.
B. (2013).- Dissocladella hauteriviana in et al., 1999 (non , 1976), another lower Urgonian Dasycladalean alga revisited.- Carnets de Géologie [Notebooks on Geology], Brest, Letter 2013/07 (CG2013_L07), p. 347-355.
Dissocladella hauteriviana in et al., 1999 (non , 1976), révision d'une autre algue dasycladale urgonienne ancienne.- Attribuée à l'origine au genre Dissocladella ( in & , 1936) de la Famille des Triploporellacées, l'espèce D. hauteriviana in et al., 1999, était supposément caractérisée par un thalle portant des verticilles de latérales constituées chacunes d'une ramification primaire trapue portant un bouquet de quatre ramifications secondaires minces à leur extrémité distale. Une révision de ces latérales démontre qu'elles se divisent plusieurs fois, et non une seule, et ce faisant diminuent de diamètre à chaque étape. L'espèce est ré-attribuée à la Famille des Thyrsoporellaceae dans une nouvelle combinaison au genre Deloffrella & , 1987. Dans l'état actuel des connaissances, sa distribution stratigraphique est relativement courte (Valanginien supérieur-Barrémien basal) ; de plus, elle disparaît plus tôt que sa compagne Polyphysacée, i.e., Clypeina paucicalcarea (, 1970), et sa répartition géographique est plus importante, ce qui en fait un bon marqueur pour les séries de plate-forme de l'Urgonien ancien.
Algues calcaires fossiles ; Dasycladales ; Thyrsoporellaceae; Deloffrella ; Hauterivien ; Barrémien basal.
Following the recent revision of Clypeina paucicalcarea (, 1970) (, 2013), this report is the second systematic revision of a key Dasycladalean alga found in lower Urgonian (Hauterivian-Lower Barremian pro parte) limestones. The scientific name (i.e., the binomial name followed by the authors' citation) of Dissocladella hauteriviana in et al., 1999 (non , 1976), summarizes the successive changes of its nomenclatural status: first described by , 1976, this species was long considered a nomen nudum (see discussion in & , 1993), before it was validated more than two decades after its original description ( et al., 1999). However, the story does not end there as we are about to write a new chapter.
Dissocladella hauteriviana was first reported from "Lower Hauterivian" strata cropping out in Marseilles
area, Provence (France), by
(1976) who illustrated 9
sections of the alga (op. cit.: Pl. 4, figs. 8-16; Fig. 1 
herein). As he thought the verticillated laterals divide only once he ascribed
his new species to the genus Dissocladella ( in
& , 1936).
He gave the following description (, 1976: p. 180): "Cette forme présente des ramifications primaires renflées (attachées directement à l'axe principal) qui donnent naissance à 4 ramifications secondaires situées dans 2 plans perpendiculaires. La portion proximale des ramifications primaires dilatées (en ampoule fertile) est légèrement rétrécie et présente l'aspect d'un court pédoncule, mal différencié. L'axe principal est cylindrique ou présente de faibles étranglements entre les verticilles" [translation: This form has swollen primary branches (attached directly to the main axis) that give rise to four secondary branches arranged in two perpendicular planes. Primary branches are dilated (in fertile ampulla), however their proximal part is slightly narrower and has the appearance of a short, poorly differentiated stalk. The main axis is cylindrical or displays slight narrowings between successive whorls]. He also gave measurements (op. cit.: p. 181), a part of them is duplicated in the first column of Table 1.
This description fits with the generic diagnosis that was given by et al. (1978: p. 90) because ( & , 1936) did not provide one, but a description of the type species: "Cylindrical to club-shaped thallus. The skeleton may be linked in successive rings. The primary branches are short, globular, or widened. At the distal end of the primary branches, there are, at least, 4 secondary phloiophorous branches having a shape similar to the primary branches. Possible adaptation of slightly modified primary branches into fertile ampulla."
Click on thumbnail to enlarge the image.
Figure 1: 8-14 & 16: Dissocladella hauteriviana in et al. 15: see discussion below regarding this figure. I retained the original numbering for these duplicates of the original photomicrographs (, 1976: Pl. 4, figs. 8-16). Because most of them came with discrete scales (x 64, 80, 84, 140, 160, 170), they were modified in order to get the same scaling factor. As a result of this unitization, they can be compared with a single graphical scale bar representing 100µm. All thin sections are stored in the J.-P. 's collection, Université de Provence, Marseilles (France) [Some rights reserved].
However, revision of the original figures as well as new finds
prove that this interpretation was wrong. For instance, the uppermost lateral of
the original fig. 14 of his Pl. 4 (, 1976;
Fig. 1.14
herein) shows that divisions occur at least at two discrete levels, i.e., the
lateral divides at least twice, and consequently that there are three orders of
ramifications within the laterals, not two as previously thought. When this point is agreed it becomes also clear,
even in complementary sections (such as Pl. 4, figs. 12 & 16, op.
cit.; Fig.
1.12 & 1.16
herein), that the branching pattern is not that advocated by
(1976). The branching is probably dichotomous: a primary divides into two
secondaries that are arranged longitudinally, these secondaries divide in turn
into two tertiaries that are arranged transversally. In transverse sections (op.
cit.: Pl. 4, figs.
9-11; Fig. 1.9-11
herein), the tertiaries form the short portions visible at the
distal ends of the laterals; the long portions in the proximal part of the laterals correspond
to the combination of the primaries and their associated secondaries.
The cruciform pattern of the secondaries observed in the
original fig. 15 of his Pl. 4 (Fig. 1.15
herein) looks like it is incompatible with the layout of the previously discussed lateral (,
1976: Pl. 4, fig.
14; Fig. 1.14
herein) that gets three distal openings set in the same plane: such a cruciform
pattern would not have more than two. However, this cruciform pattern can also be observed in
genuine Deloffrella quercifoliipora
& , 1987
(see Fig. 4.10
herein), as it depends on the orientation of the cut.
Actually the material of Dissocladella hauteriviana originally
illustrated by (1976: Pl. 4,
figs. 8-16; Fig. 1
herein) is heavily calcified. But the new material, which originates from several localities including the Gulf of
Gascony,
France (Fig. 2.2 & 2.5-6 ),
and Oman (Fig. 2.3-4, 2.8-9 & 2.13 ),
is weakly calcified. It helps for a better understanding of the division pattern of the
laterals.
Click on thumbnail to enlarge the image.
Figure 2:
1-6, 8-9 & 13: Dissocladella hauteriviana in
et al.
= Deloffrella hauteriviana, nov. comb.;
1: tangential-longitudinal section (, 1976: Pl. 4, fig. 12;
Fig. 1.12
herein) to be used as a reference specimen for direct visual comparison; 2: tangential section. Well Orion, 3148.40m, Gulf of Gascony (France) [J.
collection]; 3: subaxial section. Mu Aydin, MU base (Oman) [M.
leg.]; 4:
subtransverse section. Wadi Kamah 1, K3 (Oman) [M.
leg.]; 5: subtransverse section. Well Orion, 3148.40m, Gulf of Gascony (France) [J.
collection]; 6: subtransverse section. Well Orion, 3148.40m, Gulf of Gascony (France) [J.
collection]; 8: subtransverse section. Wadi Kamah 1, K16 (Oman) [M.
leg.]; 9: oblique section. Wadi Kamah 1, K2 (Oman) [M.
leg.]; 13: two oblique sections (one subaxial). Wadi Kamah 1, K7
(Oman) [M.
leg.]; 7, 10-12 & 14: Deloffrella quercifoliipora
& , 1987; 7: section of an
isolated lateral showing the branching pattern.- MX 85-752a, Tithonian, Veracruz-Oaxaca
(Mexico) [F.
leg.]; 10: tangential section of an heavily calcified thallus.- MX
84-78c, Tithonian, Veracruz-Oaxaca (Mexico) [F.
leg.]; 11: tangential section of a poorly calcified thallus.- MX
84-22a, Tithonian, Veracruz-Oaxaca (Mexico) [F.
leg.]; 12: tangential section of a thallus
with its original aragonitic sheath. 12071, Berriasian, N Sarajevo (Bosnia-Herzegovina)
[J.-P. leg.]; 14: "oblique section of a poorly calcified thallus, MX 85-751a = FSL
411.123" (= Pl. I, fig. 3 in
& , 1987),
Tithonian, Veracruz-Oaxaca (Mexico)
[F. leg.].
In the new material, for instance, four sections (Fig.
2.2-3, 2.9 & 2.13 )
can be compared with one of the originals (, 1976: Pl. 4, fig. 12; Fig. 1.12
herein) as they all display almost the same type of tangential section with laterals
looking like "oak leaves" ("feuilles de chêne" in French). This
structure is characteristic of the genus Deloffrella
& , 1987, with the type species D. quercifoliipora
& , 1987 (the name of which means "having
pores with the shape of an oak leaf"). The sections listed above can also
be
compared with sections of D. quercifoliipora illustrated by the authors (
& , 1987:
Pl. I, figs. 6 & 9-10; Fig.
2.10-11
herein).
The sole notable difference is the size of quercifoliipora
being larger than hauteriviana. In addition, two of
these sections (Fig. 2.3 & 2.13 )
illustrate pore shapes looking like "tea pots" ("théières" in
French) and may in turn be compared with sections of Deloffrella quercifoliipora illustrated
by the authors (op. cit.: Pl. I, figs. 5 & 7; Fig.
2.7
herein).
The combination of "oak leaf" and "tea pot" (Fig.
3 )
suggests that
the branching pattern of hauteriviana is identical to that of
quercifoliipora, that is a branching formula 1:2:4:8, which justifies the transfer of the species hauteriviana
to the genus Deloffrella
& , 1987. This combination excludes
the genus Dobuniella , 1975
(with a short branching formula
1:2:4) and Belzungia L. , 1908, or Thyrsoporella ,
1872 (with long branching formulae).
Click on thumbnail to enlarge the image.
Figure 3:
Tentative decryption of the tea pot structures (green) and oak leave structures
(orange) on a poorly preserved segment of Dissocladella hauteriviana (,
1976: Pl. 4, fig. 12). These features are better seen on Fig.
2.2-3, 2.9 & 2.13 .
The genus Deloffrella & , 1987, includes another representative: Deloffrella ? berthoui & , 2002. The species newly combined cannot be mistaken with the other two as it is by far the smallest of them all (Table 1).
Phylum Chlorophyta
Class Dasycladophyceae et al., 1995
Order Dasycladales , 1931
Family Thyrsoporellaceae & in et al., 2012
Genus Deloffrella & ,
1987
Deloffrella
hauteriviana in et al.,
1999 (non , 1976), nov.
comb.
(Figs. 1.4-14 & 1.16
- 2.1-6, 2.8-9 & 2.13
- 3
- 4.1-8 )
1976 Dissocladella
hauteriviana n.sp. (nomen nudum).- , p.
180-181, Pl. 4, figs. 8-14 & 16, Hauterivian, Provence
(France); "holotype": Pl. 4, figs. 9-10 et 16 [duplicated in Fig.
1
herein];
? 1976 Dissocladella hauteriviana n.sp. (nomen nudum).- , p. 180-181, Pl. 4, fig. 15, Hauterivian, Provence (France);
1976 Dissocladella hauteriviana (nomen nudum).- & , p. 184, Fig. 9.c, Hauterivian, Catalonia (Spain);
1982 Dissocladella hauteriviana (nomen nudum).- & , Fig. 5.g, Hauterivian, Maestrazgo (Spain);
1989 Dissocladella
hauteriviana (nomen nudum).- & ,
p. 281, Pl. II, fig. 4, Lower Hauterivian, Switzerland; Pl. II, fig. 5, (Upper ?) Hauterivian, Doubs
(France) [duplicated in Fig. 4.5-6
herein];
1993 Dissocladella
hauteriviana.- , Pl. 1, fig.
11 = Pl. 4, fig. 9 in , 1976
[duplicated in Fig. 1.9
herein], Lower Hauterivian, Marseille (France);
1993 Dissocladella hauteriviana (nomen nudum).- & , p. 30 (not illustrated);
non 1994 Dissocladella ? sp. aff. hauteriviana (nomen nudum).- , p. 152, Pl. V, fig. 1, Lower Barremian, Romania; Pl. V, figs. 2-11, Upper Barremian-Bedoulian, Romania;
1995 Dissocladella
hauteriviana (nomen nudum).- ,
p. 68, Pl. XII, figs. 1-4, Hauterivian, Switzerland [duplicated in Fig.
4.1-4
herein];
1999 Dissocladella
hauteriviana.- in et al.,
p. 234, selection of the holotype as been Pl. 4, fig. 16 in ,
1976 [duplicated in Fig. 1.16
herein];
2002 Dissocladella hauteriviana.- & , p. 130 (not illustrated);
2007 Piriferella
paucicalcarea.-
et al., Pl. 6, fig. Q (labelling error) [duplicated in Fig.
4.9
herein];
2007 Dissocladella
hauteriviana.-
et al., Pl. 6, fig. R, Upper
Hauterivian, France; Pl. 6, fig. S, Upper
Hauterivian, Switzerland [duplicated in Fig. 4.7-8
herein].
Emended diagnosis: A small-sized representative of the genus Deloffrella & , 1987. Thallus tubular, simple or branched. Laterals arranged in quincunx along the main axis. After a proximal narrowing they rapidly increase in diameter, then they divide dichotomously, probably three times, at more or less regular intervals, and doing so they stepwisely decrease in diameter. Biometric measurements (Table 1) help discriminating this species from the other representatives of the genus. The amount of calcification is variable from one specimen to the other.
| Measurements | Dissocladella hauteriviana , 1976 |
Deloffrella hauteriviana (OMAN) |
Deloffrella quercifoliipora (MEXICO) |
Deloffrella ? berthoui (PORTUGAL) |
| L | 1.1 mm | 2.5 mm | 2.18 mm | |
| D | 0.22 - 0.28 mm (0.25 in average) |
0.185 - 0.415 mm | 0.785 - 0.925 mm | 0.54 - 0.68 mm |
| d | 0.10 - 0.12 mm (0.12 in average) |
0.120 - 0.175 mm | 0.385 - 0.525 mm | 0.30 - 0.32 mm |
| d/D | 23% in average | 40 - 60% | 40 - 67% | 47 - 56% |
| l | 0.055 - 0.085 mm | 0.285 - 0.415 mm | 0.19 mm | |
| h | 0.110 mm | 0.175 mm | 0.13 mm | |
| p | 0.03 - 0.04 mm + 0.06 - 0.07 mm |
0.065 mm | 0.085 - 0.110 mm x 0.120 - 0.165 mm |
0.06 mm |
| w | 6 - 8 | 6 - 8 | 6 - 8 | ? 8 |
| w'' | 4 | 2 | 2 | 2 |
| w''' | 4 | 4 | 4 | |
| w'''' | ? 8 | 8 | ? 8 |
Table 1: Biometric data of 1) Dissocladella hauteriviana sensu , 1976, 2) Deloffrella hauteriviana (, 1999) from Oman, and 3) Deloffrella quercifoliipora & , 1987, from Mexico. Legend: L: maximum length; D: external diameter; d: diameter of the stem; h: interverticillar spacing sensu lato, i.e., distance from a reference plane in one whorl to the same plane in the next; l: length of the laterals (R); p: width of the laterals (R) near their proximal end; w: number of laterals (R) per verticil; w'': number of secondaries (R2) per primary (R1); w''': number of tertiaries (R3) per primary (R1); w'''': number of quaternaries (R4) per primary (R1).
Click on thumbnail to enlarge the image.
Figure 4: 1-4: Dissocladella hauteriviana from (1995: Pl. 12, figs. 4, 3, 2 & 1); 5-6: Dissocladella hauteriviana from & (1989: Pl. II, figs. 4-5); 7-8: Dissocladella hauteriviana from et al. (2007: Pl. 6, figs. S & R); 9: "Piriferella paucicalcarea" from et al. (2007: Pl. 6, fig. Q) [Some rights reserved]; 10: section of a lateral with a cruciform pattern in a Deloffrella quercifoliipora & , 1987, Morand borehole, -271m, Vions Fm., Upper Berriasian, Montricher, Vaud (Switzerland).
Deloffrella hauteriviana (, 1999) is reported from strata ranging in age from the Early Hauterivian to the earliest Barremian (, 1993; & , 1993; et al., 2007). There it is commonly found associated to the classical "lower" Urgonian species: Clypeina paucicalcarea (, 1970), Falsolikanella danilovae ( ex , 1978), Montiella elitzae (, 1971), Pseudoactinoporella fragilis , 1970, Salpingoporella genevensis ex et al., 1973, Montenegrella corbarica ex & , 1993, etc. However the finds with illustrations are from the Lower Hauterivian ( & , 1989; , 1993), undifferencied Hauterivian (, 1976; & , 1976; J. & , 1982; , 1995), (Upper ?) Hauterivian ( & , 1989) and Upper Hauterivian ( et al., 2007). The Omanese specimens ( in , 2011) were collected in the median part of the Lekhwair Fm (i.e., Lekhwairian regional stage), which spans the Valanginian-Lower Barremian interval (, 2008). The youngest record (, 1994) does not expressly refer to the species (op. cit.: "Dissocladella ? sp. aff. hauteriviana"). According to et al. (2007), the species is not known above the Hugii Zone (lowermost Barremian), i.e., not above the first ammonite zone of the (Lower) Barremian. Finally, its first occurrence is not accurately defined but (personal communication, Oct 7, 2013) found it below levels with Neocomites peregrinus & in Upper Valanginian strata.
This lower Urgonian (Upper Valanginian, Hauterivian and Lower
Barremian pro parte) species was found in several localities of
southwestern Europe: France (Provence: , 1976,
1993; Jura: & ,
1989;
et al., 2007), Switzerland (Jura: &
, 1989; ,
1995;
et al., 2007) and Spain (Catalonia:
&
, 1976; Maestrazgo:
& , 1982). First the find in the Gulf of
Gascony (Fig. 2.2 & 2.5-6 )
was confirming the hypothesis of a possible algal provincialism in Western Europe
(as for its companion Clypeina paucicalcarea (, 1970),
see , 2013), but the recent find in Oman (
in , 2011; Fig. 2.3-4, 2.8-9 & 2.13
herein)
demonstrates this hypothesis is not valid.
With a rather short stratigraphic range (Late Valanginian-earliest Barremian) and a broad geographical distribution (from Spain to Oman) Deloffrella hauteriviana (, 1999) should help correlating relatively well-known European sections and their commonly poorly age-constrained Middle-East counterparts. In conclusion, it is potentially a good index fossil for lower Urgonian carbonate platform series of the Tethyan realm.
The author thanks Ioan , Filippo , and Felix , who kindly reviewed the manuscript and suggested some additions to improve its impact. It is worth mentioning that the Systematics views expressed in this letter are not shared by Marc André . The author also expresses his appreciation to Stephen for his help in polishing the English text of the original manuscript. Last but not least, special mention goes to Jean-Pierre for sharing information on his Dissocladella hauteriviana and for the gift of nicely preserved specimens of Deloffrella quercifoliipora he collected many years ago in Bosnia-Herzegovina.
J.-P., P., M.A., R. & M. (1978).- Les Algues Dasycladales du Jurassique et du Crétacé ; révision critique.- Géobios, Villeurbanne, Mémoire spécial, n° 2, 330 p.
M.C. (1995).- Importance des discontinuités dans l'enregistrement sédimentaire de l'Urgonien jurassien. Micropaléontologie, sédimentologie, minéralogie et stratigraphie séquentielle.- Géologie Alpine, Grenoble, Mémoire HS n° 24, 299 p.
I.I. (1994).- Algues calcaires de la zone de Reşiţa-Moldova Nouă (Carpathes Méridionales, Roumanie).- Revue de Paléobiologie, Genève, vol. 13, n° 1, p. 147–209 (XXII Pls.).
J. & P. (1982).- La plate-forme hauterivienne des Ibérides sud-orientales (Espagne) et ses environnements bio-sédimentaires.- Cretaceous Research, London, vol. 3, n° 1-2, p. 91-101.
B., J., M., R., R., S., E., R., A. D., B., J. & M. (2007).- Dating and progradation of the Urgonian limestone from the Swiss Jura to South-East France.- Zeitschrift der Deutschen Gesellschaft für Geowissenschaften, Stuttgart, Bd. 158, Heft 4, p. 1025-1062.
M.A. & J.-P. (1989).- Les algues calcaires des formations carbonatées de l'Hauterivien-Barrémien pro parte du Jura vaudois et neuchâtelois (Suisse).- Mémoires de la Société neuchâteloise des Sciences naturelles, t. XI, p. 277–290 (Pls. I-II).
M.A. & B. (1976).- Hauterivian-Albian Dasycladaceae from Urgonian limestones in the French and Spanish eastern Pyrenees.- Geologica romana, vol. XV, p. 175–197.
E. (2011, unpublished).- Architecture stratigraphique et sédimentologique des systèmes carbonatés progradants : étude intégrée en sismique et à l'affleurement du système Lekhwair/Habshan/Salil au Sultanat d'Oman (Crétacé inférieur), et applications réservoir. - Thèse de Doctorat en Science de la Terre, Université Michel de Montaigne - Bordeaux 3, 437 p.
G.F. (1975).- Transported algae as indicators of different marine habitats in the English Middle Jurassic.- Palaeontology, London, vol. 18, part 2, p. 351-366 (Pls. 48-50).
B. (1992).- Les algues et foraminifères benthiques du Jurassique supérieur et du Crétacé inférieur du Sénégal.- Journal of African Earth Sciences, Oxford, vol. 14, n° 2, p. 239-253 (5 Pls.).
B. (2008).- Holostratigraphy of the Kahmah regional Series in Oman, Qatar, and the United Arab Emirates.- Carnets de Géologie [Notebooks on Geology], Brest, Article 2008/07 (CG2008_A07), 33 p.
B. (2013).- Heteroporella ? paucicalcarea (, 1970), an Urgonian Dasycladalean alga revisited.- Carnets de Géologie [Notebooks on Geology], Brest, Letter 2013/01 (CG2013_L01), p. 59-65.
B. & P.-Y. (2002).- Algues calcaires fossiles, nouvelles ou peu connues, du Portugal. 1ère partie - New or little known fossil calcareous algae from Portugal. Part I. In: I.I. & S. (eds.), Research advances in calcareous algae and microbial carbonates.- Proceedings of the 4th IFAA Regional Meeting (Cluj-Napoca, August 29 - September 5, 2001), Presa Universitara Clujeana, Cluj-Napoca, p. 117-126.
B. & F. (2002).- Thyrsoporella pseudoperplexa n. sp., une Dasycladacée (algue verte calcaire) du Jurassique supérieur téthysien. In: I.I. & S. (eds.), Research advances in calcareous algae and microbial carbonates.- Proceedings of the 4th IFAA Regional Meeting (Cluj-Napoca, August 29 - September 5, 2001), Presa Universitara Clujeana, Cluj-Napoca, p. 127-133.
B. & R. (1993).- Inventaire des Algues Dasycladales fossiles. II° partie- Les Algues Dasycladales du Jurassique et du Crétacé.- Revue de Paléobiologie, Genève, vol. 12, n° 1, p. 19-65.
B., D., I.I. & P. (2012).- Brasiliporella, a new mid-Cretaceous dasycladacean genus: the earliest record of the Tribe Batophoreae.- Facies, Erlangen, vol. 59, n° 1, p. 207-220.
B. & F. (1987).- Deloffrella quercifoliipora n.gen. n.sp., une Algue Dasycladacée nouvelle du Kimméridgien et du Portlandien du Sud-Est du Mexique.- Bulletin de la Société géologique de France, Paris, (8ème série), t. III, n° 6, p. 1089-1096 (Pl. I).
C.W. (1872).- Die sogenannten Nulliporen (Lithothamnium und Dactylopora) und ihre Betheiligung an der Zusammensetzung der Kalkgesteine. Zweiter Theil: Die Nulliporen des Thierreichs (Dactyloporideae) nebst Nachtrag zum ersten Theile.- Abh. d. II. Cl. d. k. Ak. d. Wiss, (Math. phys. Cl.), München, Band XI, Abh. I, p. 231-290 (Pls. D.I-IV).
J.-P. (1976).- Les calcaires urgoniens de Provence (Valanginien-Aptien inférieur). Stratigraphie, paléontologie, les paléoenvironnements et leur évolution.- Thèse Doctorat ès Sciences, Université d'Aix-Marseille II, 3 vols., 445 p. (60 Pls.).
J.-P. (1993).- Early Cretaceous Dasycladales biostratigraphy from Provence and adjacents regions (South of France, Switzerland, Spain). A reference for Mesogean correlations. In: F., P. & M. (eds.), Studies on fossil algae.- Bolletino della Società Paleontologica Italiana, Modena, Special Volume n° 1, p. 311-324.
J.-P., I.I., A. & H. (1999).- Nouvelles espèces de Dasycladales du Crétacé inférieur de Provence (SE France).- Revue de Micropaléontologie, Paris, vol. 42, n° 3, p. 231-243 (2 Pls.).
L. (1908).- Deux Algues siphonées verticillées du Thanétien de Boncourt (Oise).- Bulletin de la Société géologique de France, Paris, 4° série, t. VIII, p. 96-99.
L.R. & J. von (1936).- Fossil algae from the uppermost Cretaceous beds (the Niniyur Group) of the Trichinopoly district, S. India.- Memoirs of the geological Survey of India, Palaeontologia Indica, Calcutta, New Series, vol. XXI, n° 4, 49 p. (Pls. I-VI).