New Dasycladales and microbiota from the lowermost Valanginian of the Mirdita Zone

A rich diversified algal microbiota is described from the lowermost Valanginian limestone reworked in the Upper Cretaceous clastics of the Metohija Cretaceous Unit (Mirdita Zone). Two new dasycladalean taxa are introduced: Zujovicella nov. gen. (type species Suppiluliumaella gocanini RADOI^I], 1972) and Furcoporella vasilijesimici nov. sp. Microbiota of this bioclastic limestone (containing dominantly corals and other metazoan fragments) consists of algae, microbial epiliths, microproblematica, foraminifera, calcispongie and a few calpionellids of the Calpionellopsis Zone – Calpionellopsis oblonga (CADISCH), Remaniella cadischiana (COLOM), Tinntinopsella carpathica (MURGEANU & FILIPESCU). Besides the new taxa dasycladales also associated are: Salpingoporella pygmaea (GÜMBEL), Salpingoporella sp., Gyroporella lukicae SOKA^ & VELI], Neomerinae and several indetermined taxa. Lithocodium aggregatum (ELLIOTT), other encrusting Lithocodioidea and different microbial epiliths are an important component of this microbiota association. Foraminiferal assemblage consists of: Coscinophragma cf. C. cribrosum (REUSS), Mohlerina basiliensis (MOHLER), Nautiloculina bronnimanni ARNAUD-VANNEAU & PEYBERNÈS, Neotrocholina valdensis REICHEL, Neotrocholina sp. Placopsilina sp., Protopeneroplis trochangulata SEPTFONTAINE, Trocholina alpina (LEUPOLD), Trocholina delphinensis ARNAUD-VANNEAU, BOISSEAU & DARSAC, Trocholina sp., lituolids, miliolids and other small benthic taxa. The analyzed lowermost Valanginian limestone originated from the topmost sequence of the Tithonian–Neocomian cycle which ended as a consequence of the Main Cimmerian Events, which occerred, as in the Vardar zone, after the lowermost Valanginian. Cretaceous cycle (Mirdita Crtaceous Unit) begins in the Hauterivian.


Introduction
Dasycladales Suppiluliumaella gocanini were described from Lower Valanginian limestone of the Orahovac region, Mirdita Zone (Fig. 1).In the locality between the villages of Kravoserija and Boka this limestone was not found in situ (RADOI^I], 1972).According to the Geological Map, the sheet Orahovac 1:100 000 (LON^ARE-VI], 1986), this area is covered by Upper Cretaceous carbonate clastics.On the footpath between the mentioned villages, in a small outcrop of 2-2.5 m thick clastics, horizontally arranged cobblestones in the microbreccia bed were observed.One of them (cobble of cca 15×12 cm) was limestone with large (to 6 cm) coral and other metazoan fragments.On the surface of broken pieces, in the matrix between large fragments (bioclastic packstone-rudstone), some dasycladalean, different coating algal and microbial structures and foraminifera, were observed under a lens.The matrix between large metazoan fragments was used for thin slides (17), in some of which sections of Suppiluliumaella gocanini were found.
The purpose of this paper was the revision of Suppiluliumaella gocanini, based on which Zujovicella nov.gen. is described, and the presentation rich associated biota including new dasycladalean species Furcoporella vasilijesimici.

Kravoseria Coble
The studied limestone coble bears abundant diversified biota.Corals (different species) were its most important component, calcisponge, hydrozoa, mollusk and other metazoa remains were also present.The microbiota consisted of algae (Dasycladales, Udoteaceae, Lithocodioidea), microbial epiliths, foraminifera and miroproblematica; while calpionellids were represented by only a few specimens.The corals were an especially alluring substrate for encrusting algae and similar microbial epiliths.Other metazoan remains and dasycladales were also the subject of epilithic activity.
The list of foraminifera includes: Coscinophragma The presence of calpionellids is important for the dating of this coble: Calpionellopsis oblonga (CADISCH) (Fig. 2A), Remaniella cadishiana (COLOM) (Fig. 2B) and Tintinnopsella carpathica MURGEANU & FILIPESCU indicate its lowermost Valanginian age (Calpionellopsis Zone).This Valanginian limestone originates from the youngest sediments of the Tithonian-Neocomian cycle, which ended as a consequence of the Main Late Cimmerian Events.A new Cretaceous cycle begins discontinuously in Hauterivian (Metohija Cretaceous Unit).Valanginian shallow water limestone in the area of this cretaceous unit was not known in situ.Resedimented benthic biota of this age occurs in some microbreccia and calcarenite beds of the proximal basinal Tithonian--Neocomian succession, outcropping in the same area.
Valanginian limestone with corals as the essential component and Zujovicella gocanini was deposited in the reef thallus area.

Paleontology Observation on Suppiluliumaella gocanini RADOI^I], 1972
The genus Suppiluliumaella ELLIOTT, according to the original diagnosis, is characterized by "verticils of long thin primaries with a large conspicuous terminal swelling, each dividing into very short swollen secondaries".
The calcareous sheet of the holotype (ELLIOTT, 1968, Pl. 3, Fig. 1) is micritized, whereas secondary laterals are not well preserved.The presence of secondaries are discernable only at two or three points in this section.The paratype in Fig. 3 is an oblique section corresponding to an inclination of the stalky portion of primaries, while the secondary laterals, in central part of the fragment, were cut obliquely -therefore it is not their real length (they are not so short).The impression that the secondary laterals of some Suppiluliumaella species grow out from primaries in the form of a finger-like continuation (SOKA^& NIKLER, 1983) is not a primary feature -it is only apparent (see BARATTOLO, 1984).
At first sight, Suppiluliumaella gocanini (densely set funnel-like whorls built of very long tubular primary laterals which touch each other over a considerable part of their length and form terminal swellings; primaries carry at their ends tufts of the secondary laterals) resembles only the type-species Suppiluliumaella polyreme.In fact it differs from any known Suppiluliumaella species by having: 1. Larger (wider and longer) primary laterals, with apparent terminal swellings; 2. Quite different, trochophorous secondary laterals which could be extended hairy growth.In other species, although not fully preserved, secondary laterals are described as phloiophorous (ELLIOTT, 1968;BAKALOVA, 1971;DRAGASTAN, 1978DRAGASTAN, , 1989;;BARATTOLO, 1984).
These differences are the reason for the doubt as to whether this species belongs to the genus Suppiluliumaella.Reexamination of Suppiluliumaella gocanini type material (and some new sections) led to the conclusion that this species is not a Suppiluliumaella.The pri-mary laterals are only apparently terminated by a "swollen" portion.In fact, a tuft of trochophorous secondaries starts from the top of the tubular primary laterals, enclosing a fertile ampulla.These characteristics indicate the affiliation of this species to the tribus Dasycladeae.

Type species. Suppilluliumaella gocanini RADOI^I], 1972
Origin of name.The genus is dedicated to Prof. JOVAN @UJOVI] (1856-1936), founder of geology in Serbia and the author of the first geological map of Serbia printed in Vienna 1886.
Diagnosis.Cylindrical or club-shaped thallus with densely set whorls, unfertile whorls can also be present.The fertile whorls consist of densely arranged cylindrical primary laterals each giving a second whorl segment: tufts of trochophorous secondary laterals and a fertile ampulla situated in the center of the tuft.Surface of the calcareous sheet indentated.
Comparisons.The genus Neomeris has a cylindrical to clavate thallus, ampulla and two secondary laterals placed in one plane, the thallus surface is faceted.Cymopolia has an anarticulated thallus and primaries with ampulla and 4-8 secondary laterals enlarged at the outer ends forming a faceted surface Zujovicella gocanini (RADOI^I], 1972) nov. comb. Fig. 3;Pl. 1, Figs. l-6;Pl. 2, Figs. l-8 Diagnosis.A large slightly club-shaped thallus of differentiated structure -with a lower unfertile part.A wide central cavity.Densely set funnel-like whorls consisting of close-fitted laterals inclined upward at an angle of 65 to 75° from the horizontal.The long and large rounded at the top cylindrical primary laterals bear a large ooidal fertile ampulla and a tuft of 5 or 6 long trochophorous secondary laterals around the ampulla (Figs. 3,4).Calcareous skeleton compact, mainly around the distal part of the whorls.The surface of the skeleton is indentated due to the trochophorous form of the second whorl segment.
Dimension (in mm) (based on some additional sections than in 1972; the slightly oblique, deep-tangential section of the holotype is not relevant for the D and d values).
Description.It seems that not every whorl in the fertile portion of the thallus is fertile.The fertile ampulla, placed in the center of the rounded at the top primaries, is protected by secondary laterals of a peculiar trochophorous form (Figs. 3,4;Pl. 2,Fig. 4).Starting as a tubular of 0.048 mm diameter, the secondary laterals become largest (0.160 mm) at the middle of the length, closing the ampulla and distally thinning (Pl.2, Fig. 4) probably extending in a hairy growth.The cross and oblique sections of the distal tuft portion have a coptocampylodon form (Pl. 2, Fig. 7; Pl. 8, Fig. 10).
The inner part of the thallus -main axis and first segment of the whorls -is usually not calcified.According to a reconstruction, the main axis was narrow, probably not wider than 25% of the external diameter.Calcification was limited to the distal area of the whorls, diminishing toward the interior.The membrane of the primaries, partly preserved in only some specimens, was very thinly calcified (Pl. 1,Figs. l,3).The membrane of the fertile ampulla and secondaries was also thinly encrusted (visible as a thin dark line in diverse sections).In fact, the compact calcareous skeleton is formed by a calcified mucilage layer around the secondaries (Pl. 1,Figs. 3,5;Pl. 2,Figs. 4,5).Secondary sparry calcite had deposited (before the sheet was coated) mainly in the secondaries and sometimes in the ampulla or inside the primaries.In the slightly oblique deep-tangential section (holotype, Pl. 1,Figs. 1,[3][4], differently preserved second whorl segments are visible.Its different aspect depends also on the cut plane.Hence, for slightly recrystallized segments (= ampullae and basal parts of the secondaries shown in Pl. 1, Fig. 4, arrow 1) it can be wrongly interpreted that the ampulla ("swelling") bears finger-like short secondaries.A similar apparent relation between the ampulla and "short" secondaries is shown by arrow 2. Tangentially cut primaries and tufts are indicated by arrow 3.
The indentated skeleton surface was usually eroded and often corroded by microbial epiliths.The corroding effect in some specimens appears to have been locally arrested.In such cases it seems that the epiliths even contributed to the preservation of some structure by protecting the skeleton from further erosion and dissolution and moderating the effect of further diagenetic processes.
Pl. 4, Fig. 5 Neomerinae are a minor component in this Valanginian algal association.Only an oblique section of a  compact cylindrical skeleton (Drimella?)and a small fragment of another species have been found.The fragment shown in the same plate Fig. 6, could be related to Neomerinae.
Family Triploporaceae (PIA 1920) BERGER & KAEVER, 1992Tribus Salpingoporelleae BASSOULLET et al., 1979 Genus Furcoporella PIA (in TRAUTH), 1918 The genus Furcoporela was introduced by PIA from the Middle Eocene in Austria with the species Furcoporella diplopora (PIA, 1918).The simple cylindrical thallus of this species is characterized by spaced whorls of horizontally disposed two orders of laterals.The primary laterals are short, divided into two divergent secondaries enlarged to the exterior.Hitherto, the genus was monospecific.(Based on the characteristic of a new species, upward inclined laterals, diagnosis of thus genus should be amplified).

Furcoporella vasilijesimici n. sp. Pl. 3, Figs. 1-3
Origin of name.The species is dedicated to Dr VASILIJE SIMI] , one of the pioneers of modern geology and paleontology in Serbia.
Holotype.longitudinal oblique section shown in Pl. 3, Fig. 1, thin slide RR2190, the author's collection deposited in the Geozavod -Geological Institute in Belgrade.
Isotypes.Specimens in thin slides RR2184 and 2201 figured in Pl. 3, and two poorly preserved specimens in thin slides RR2186 and 2189.
Diagnosis.Thallus cylindrical with a relatively large axis and spaced whorls consisting of two order of laterals inclined upward, alternating from one whorl to the next.Short primary laterals divided in two vesicular secondaries, slightly swollen at the distal end.Secondary laterals are in a somewhat irregular, oblique position.Calcification is massive, from the axis to the subcortical area.Description.The peculiarity of this species lies in the position of the secondary laterals which is reflected in more advanced corrosion and dissolution in some parts of the skeleton.The upward inclined secondaries are irregularly disposed, more in the distal area.They are arranged in an oblique to radial plane, which is evident in the transversal or slightly oblique-transversal sections (Pl 3, Figs, 2 and 3).
Comparison.The thallus structure of this species differs from Furcoporella diplopora in having inclined laterals, i.e. funnel like whorls and a different position of the secondaries.
Salpingoporella ?sp.Pl. 4, Fig. 10 Fragment of the oblique section showing a specimen with regularly arranged dense whorls of primary laterals (35 or more per whorl).
Genus Gyroporella GÜMBEL 1872, emend.BENECKE, 1878 According to BASSOULLET et al., (1978), the genotype Gyroporella vesiculifera is a species with "Aspondyl disposition of laterals of one single order of vesiculiferous type".ZANIN-BURI (1965) in a study of carbonate algae from Trias of the Lombardian Pre-alpes presented very well preserved euspondyle specimens of Gyroporella vesiculifera from the Norian of the Dolomites (imprints on a rock surface and sections in thin slides: Pl. 46,Figs. 1,2,and Pl. 47).In these specimens "I pori sono fittamente and omogeneamente disposti tanto che sono in contatto gli uni cogli altri, la loro disposizione e cosi regolare che si puo trovare un perfetto allineamento in file orizzontali, verticali e diagonali." As to the disposition of the laterals (aspondyle or euspondyle) see discussion by BARATTOLO et al. (1993).According these authors, the possibility should not be excluded that the genera Gyroporella and Griphoporella PIA are synonyms, which could be resolved by revision of Gyroporella vesiculifera type material.
According to the original description, the thin calcareous skeleton is perforated by numerous pores (23-30) of vesiculiferous laterals which "tending to be arranged in more or less clearly marked whorls with approximately alternating neighbouring whorls which are not always clearly visible" SENOWBARI-DARYAN et al. (1994), considering that the genus Gyroporella is aspondyle, proposed new combination: Anisoporella lukicae (SOKA^& VELI]).The comparison with Anisoporella has not been justified.The genus Anisoporella has an entirely different structure: "L'arrangement des rameaux se fait en general par serie de deux (= double verticilles) come chez Oligoporella."L'alternance des rameaux est presque la regle, mais les pores sont tantot disposes en quinquonce, tantot par paires, tantot par groupes de trios.Ces trois modes de distribution se retrouvent alternativement sur le meme manchon, dans un ordre de succession quelconque" (BOTTERON, 1961).
In the Kravoseria limestone coble, Gyroporella lukicae is a relatively frequent fossil (cylindrical skeleton and numerous fragments), and of very variable dimensions.Besides specimens which correspond to the type material, there are larger forms with densely set more numerous laterals in the whorls (Pl. 3,Figs. 8,10).The peculiarity of the specimen in Pl. 3, Fig. 9 is the supraterminal growth (note: evidently thinner and denser laterals at top of the rounded thallus).
Dimensions (in mm; extreme values given in brackets): Dasycladales div.sp.
Pl. 9, Figs.3-6 The transverse section of Nipponophycus ramosus illustrated by SENOWBARY-DARYAN et al. (1994) in Pl. 7, Fig. 3, and the transverse section of Nipponophycus sp.illustrated in the same plate, Fig. 8 have a clearly lobed periphery.These specimens differ from numerous Nipponophycus talli presented in the same paper in Pl. 7. Poorly preserved, recrystallized specimens of this type are found in the studied thin slides.Some oblique sections, such as those illustrated in Pl. 9, Figs.3-6, indicate a segmented morphology of the thallus (short hemispherical somewhat irregular flabelliform segments) These sections are very similar to the oblique section of a segmented thallus showed by SANOWBARY-DARYAN et al. (1994) in Pl. 5, Fig. 15 as Pinnatiporidium sp.cf Pinnatiporidium cylindricum DRAGASTAN.
The genus Pinnatiporidium is characterized by a segmented thallus with superficial constrictions and segments with three distinct zones: central, lateral (with two types of branching) and cortical (DRAGASTAN, 1990).As shown by the illustrated specimens, these structures are generally not observable due to poorly preserved or recrystallized thalli; the central medular zone was not preserved, while relatively large, second order branches are visible only in the section on Pl. 9, Fig. 4, while treads of thin branching of the cortical zone can be soon on the same plate, Fig. 5.
Pl. 9, Fig. 8 The thallus of Felixporidium, "built of bush-like hemispherical segments or flabellae," crossed by a large medullary siphon which, in every segment, is followed by two order siphons (filaments) "branched dichotomically and disposed radially".Felixporidium is related to Pinnatiporidium DRAGASTAN, 1990 by the similar form and structure of the thallus.The differences between the two genera a the generic level is an open question.
In the longitudinal-oblique section of the illustrated specimen, the flabelliform arranged three order laterals appertaining to successive segments are well preserved.Similar flabelliform branching can be discerned on the poorly preserved specimen of Felixporidium alpidicum DRAGASTAN, 1999, illustrated in the original publication on Pl. 6, Fig. 8.This species, according to DRAGASTAN, has an inner morphology which is very close to Pinnatiporidium cylindricum, (type species of the genus).

Genus Nipponophycus YABE & TOYAMA, 1928
Nipponophycus ramosus YABE & TOYAMA, 1928 Pl. 9, Figs.1-2 The few specimens assigned to this species with a cylindrical branching thallus are strongly recrystallized: the medulare zone is represented by a narrow cavity, The encrusting alga Lithocodium aggregatum characterized by a high degree of variability in both: the thallus morphology and, especially, the internal structure (ELLIOTT, 1956;BANNER et al., 1990).The Lithocodium nodules are usually formed by superimposed thalli.This is, certainly, the green alga with the most variable features.Therefore, it seems justified, as noted by BAN-NER et al., that the genus Lithocodium "may subjectively be monotypic".
In the same Lithocodium thallus, different arrangements the structure of the medulla and cortex can be observed.The specimen illustrated on Pl. 5, Fig. 4 has one type of Lithocodium structure developed only in a part of the growth: a coarse medula followed by some order of variously ramifing filaments, ending with short fine cortical filaments covered by a thin calcareous sheet (Fig. 7 shows detail of Fig. 4).Laterally, this structure grades into a somewhat reduced subcortical zone similar to those of the thallus in the Fig. 3, or grades in a part of the thallus, apparently "terminated" without these structures.
The narrow elongate growth (aspect in the section!) on Pl. 5, Fig. 3 has, immediately below the cortical structure, relatively large septate filaments of the medulla.Here, the ramification is reduced: large medulla filaments immediately give numerous very short fine cortical (bifurcate?) filaments terminating in a thin well preserved calcareous sheet Solitary corals are usually encrusted by a Lithocodium or other Lithocodioidea crust and more or less corroded (Pl. 6,Figs. 3,4,); often it is superimposed by a new Lithocodium or another encrusting growth.
Elements encased and more or less corroded by Lithocodium are metazoan, their fragments, foramini-fera, dasycladales, other algal and problematic structures and different rock grains.The corroding process can results in a more or less disintegrated substratum.It seems that disintegration is usually not an effect of only Lithocodioidea activity but also of some preceding microbial chasmoendoliths.For example, in the pores between the skeleton elements of corals and hydrozoa encrusted by Lithocodioidea, the earlier activity of microbial chasmoendolith is evident.
Lithocodium aggregatum is one of the widely distributed fossils (Upper Jurassic -Albian, BANNER et al., 1990) particularly in the Lower Cretaceous limestone of both Tethyan margins.In the analyzed limestone, Lithocodium aggregatum and similar encrusting growth are important components.

Lithocodioidea KL11
Pl. 9, Fig. 9 The thin compact crust of the only specimen in the available thin slides is characterized by thin bifurcate filaments, perpendicular or subperpendicular to the surface.Similar crust ("aff.KL11") is shown in Fig. 10 on the same plate

Lithocodioidea KL12
Pl. 8 Fig. 2 Agglomeration (encased in Lithocodium) of thinwalled, subcircular and irregular rounded cells is the single specimen of this type of structure.

Lithocodioidea KL13
Pl. 8, Fig. 1 A crust with a peculiar subcrustal structure is part of the superimposed growth on Lithocodium.

Incertae Sedis (algae)
"Tubiphytes" morronensis CRESCENTI, 1969 Pl. 9, Fig. 7 The enigmatic fossil "Tubiphytes" morronensis was widespread in the Upper Jurassic and Lower Cretaceous reef areas of both Tethyan margins.Many of those specimens represent a differentiated axial "nubeculariform" part from a coated growth (probably of microbial nature).This taxon is not frequent in the Kravoserija limestone.
"Gryphoporella" perforatissima CAROZZI, 1955 Pl. 3, Fig. 9 p. p. to this CAROZZI'S species.According to BASSOULLET et al. (1978), dasycladalean affinity of this species is doubtful.Fossils related to CAROZZI'S species were described as Gryphoporella piae by DRAGASTAN in 1971, then, based on the same specimens, finding similarity with Trinocladus pinarensis KEIJZER, DRAGASTAN in 1978 introduced a new genus Pseudotrinocladus.The doubt in the dasycladalean nature of this species seems justified.This fossil could be related to udoteacean algae.

Microproblematica KL15
Pl. 8, Fig. 7 The small claviform corpuscles with a thin regularly reticulate wall are parts of a larger structure.
Koskinobullina socialis is interpreted as "small vesicular individuals forming colonies of varying dimensions which are fixed upon a substrate" "either as solitary individuals or, more frequently, in the form of crust-like agglomeration" (CHERCHI & SCHROEDER, 1984).
Lithocodium and similar structures alternate with crust-like Koskinobullina agglomerations as those shown on Pl. 7, Fig. 1.In the same plate, Fig. 2, the colonia of Koskinobullina socialis is covered by rodophycean alga.

Microbial epiliths and other microbiota
Microbial epilith KL16 Pl. 6, Fig. 6 Lammelar (stromatolithic) microbial buildup with fine horizontal filaments.The same structure in Fig. 1, also developed on Lithocodium aggregatum nodula, is poorly preserved and is not clearly visible in this photograph.KL17 and KL18 Pl. 8,Figs. 3,4 The microbial crust coating of an about 7.2 mm long bioclast seems homogeneous without a clear internal structure (except for a few large pores).On the upper side of the bioclast the microbial crust is thicker with a tuberculate surface (Pl.8, Fig. 3).Meanwhile, on the photograph made at low exposition, two different organisms are evident.In the first thin encrusting micrit-ic layer (KL17, calcisponge?crust, Fig. 4) perpendicular to the surface, wedge-like spicules with upward oriented wider ends were noted (wedge-like form of spicules could be apparent!).This even thick layer was encrusted by microbialite of a tuberculate surface (KL18, Fig. 4) in which a fine tubular filamentous tissue could be discerned.

Microbial epilith
The thin crust of atuberculate surface, in Fig. 8 on plate 6, corroding a mollusk shell has large pores only in the figured part of the growth.Excluding this element of the structure, the tissue of the crust seems similar to that of the microbialite KL18.

Microbial epilith KL19
Pl. 7, Fig. 3 On a part of a, Lithocodium mélange nodula, a fine complex crust was developed.It consists of a barely discernible, densely porous micritic tissue covered by thin porous calcitic lamina.

Microbial epilith KL20
Pl. 6, Fig. 7 a, b On the same melange nodula, in two parts, a crust of fine, chain-like, slightly interlaced threads were developed.They are longitudinal sections of fine tubules of 0.016 mm diameter.In Fig. 7b transversal sections of tubules are visible.

Microbial chasmoendolith KL22
Pl. 8, Fig. 8 In this case, the pores in the Cladocoropsis? skeleton has been lined by the microbial chasmoendolit.
Calcisponges, usually not well preserved, in the analyzed limestone are more abundant than immediately apparent.Some of them are illustrated on Plates 7 (Aka sp.).