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Bakhtiariella, a new genus of Larger Benthic Foraminifera is described from the upper Maastrichtian Tarbur Formation of Iran. The new taxon is characterised by a trochospirally coiled initial test ...

In his monograph on Mesozoic-Cenozoic Larger Benthic Foraminifera from the area of Middle East and south-western Asia, Henson (1948) erected the genus Dictyconella for more or less "compressed-conical" dictyoconids including D. complanata (type-species) and D. minima. Both are however, structurally completely different, e.g. aligned (in the latter) versus alternating structural elements (in the former), and cannot either belong to the same genus or the same subfamily (Dictyoconinae versus Dictyorbitolininae). Therefore, the new genus Gusicella is erected with the type-species Dictyoconella minima, resulting in the new combination Gusicella minima. Gusicella represents the only taxon of the Dictyorbitolininae in the Upper Cretaceous Global Community Maturation Cycle of Larger Benthic Foraminifera (here: conical agglutinated). Due to the revision, Dictyoconella is described as a monospecific genus and an assumed Maastrichtian newcomer which, like Gusicella, became extinct shortly afterwards, namely at the K-Pg boundary mass-extinction event. Both taxa appear to be restricted to the former Arabian Plate of the southern Neotethyan margin. The new data provided are based on material from the Maastrichtian Tarbur Formation of southwestern Iran (Zagros Zone).

The micropalaeontological inventory of the shallow-water carbonates of the Paleocene Chehel-Kaman Formation cropping out in the Kopet-Dagh Basin of north-eastern Iran is poorly known. New sampling has evidenced for the first time the occurrence of layers with abundant calcareous green algae including Dasycladales and Halimedaceae. The following dasycladalean taxa have been observed: Jodotella veslensis Morellet & Morellet, Cymopolia cf. mayaense Johnson & Kaska, Neomeris plagnensis Deloffre, Thyrsoporella-Trinocladus, Uteria aff. merienda (Elliott) and Acicularia div. sp. The studied section is devoid of larger benthic foraminifera and can be referred to the middle-upper Paleocene (SBZ 2-4) due to the presence of Rahaghia khorassanica (Rahaghi). Some of the dasycladalean taxa are herein reported for the first time not only from Iran but also the Central Neotethyan realm.

A new larger benthic foraminifera is described as Broeckinella hensoni from the upper Maastrichtian Tarbur Formation of SW Iran (Zagros Zone). In comparison to the type species of the genus, Broeckinella arabica Henson, which also occurs in the Tarbur Formation, the new species has distinctly larger dimensions (e.g., size and thickness of test, chamber height). The first record of a microspheric specimen of B. arabica shows previously unrecorded annular chambers in the final test stage. Therefore, the generic diagnosis is herein emended. In the Tarbur Formation, both B. hensoni n. sp. and B. arabica occur in foraminiferal-algal wackestones. However, B. arabica occurs in a wider range of microfacies, including packstones and grainstones. It is assumed that Broeckinella originated in the Upper Cretaceous with Broeckinella neumannae Gendrot. The upper Albian Broeckinella aragonensis Peybernès is herein transferred to the porcellaneous genus Peneroplis Montfort.

The upper Palaeocene shallow-water carbonates of the Qorban member (Sachun Formation) in Iran are characterised by a well-diversified larger Foraminifera and green algae assemblages. A new ornatoro...

The upper Maastrichtian Tarbur Formation of the Zagros Zone, SW Iran, contains a rich assemblage of larger benthic Foraminifera including agglutinating, porcelaneous, and lamellar-perforate taxa. T...

A new microgranular-imperforate foraminifera, attributed to the family Pfenderinidae, is described as Pseudochablaisia subglobosa gen. et sp. nov. from the upper Maastrichtian Tarbur Formation (Zagros Zone, SW Iran). It occurs in inner platform wackestones/packstones associated with other larger benthic foraminifera (e.g., Loftusia, Omphalocyclus, Gyroconulina) and dasycladacean green algae (e.g., Cymopolia, Dissocladella, Thyrsoporella). Pseudochablaisia gen. nov. is compared with possible ancestral morphotypes, the Middle Jurassic to Oxfordian homeomorph Chablaisia Septfontaine, 1978 and sections of a taxon classically assigned to the middle-Late Cretaceous “Nezzazatinella” Darmoian (1976) which type-material is incompletely known from loose isolated specimens. These two homeomorphic taxa and the new genus Pseudochablaisia possess a trochospirally coiled test, with a pseudokeriothecal wall texture (sometimes hardly visible). The central structure of the test comprises an umbilical (“siphonal”) hollow columella in early stages continuing in a deep umbilical cavity in later stages. The chamber interior is occupied by a zone of coalescence of the septa and a septal button, lacking in sections of “Nezzazatinella".

A new Dasycladale is described as Dissocladella? chahtorshiana Rashidi & Schlagintweit n. sp. from Selandian carbonates of Mount Chah Torsh, Central Iran (type locality). Other occurrence is from the Sistan Suture Zone of Eastern Iran (Selandian?, Thanetian?). The medium-sized taxon displays cylindrical to slightly claviform thalli with a relatively large main axis bearing alternating primaries of variable shape. The latter show either slowly widening towards the distal end or are club-shaped displaying very short secondaries. The morphological variability of the primaries, both typical and atypical for Dissocladella, account for some doubts on the generic assignment of the new species. Dissocladella? chahtorshiana occurs in bioclastic packstones with Cymopolia mayaense Johnson & Kaska, Acroporella cf. anceps Segonzac, Halimeda sp., and benthic foraminifera (e.g., soritiids) at its type locality.

The Maastrichtian carbonates of the Tarbur Formation from the Zagros zone (SW Iran) are very rich in larger Foraminifera. Additionally, smaller benthic Foraminifera occur as well, one of them presented here as Zagrosaria pinnata gen. et sp. nov. It occurs abundantly at the Mandegan section within two levels corresponding to the lower photic zone. Based on the existence of a central pile along with an umbilical plate, and the lacks of true interiomarginal apertures, likely represented by a perforate surface, the suprageneric placing of Zagrosaria gen. nov. remains controversial. The ultimate aperture is represented by a central elongate double-bifid slot that arguably lies on a finely perforated and heavy feathered apertural face. Based on the reduced dimensions and lack of dimorphism the new taxon could be considered an epifaunal or shallow-infaunal r-strategist.

The shell architecture of Fissoelphidium operculferum Smout from the Tarbur Formation, Maastrichtian of Zagros, has been re-studied. Based on the characters of the canal system geometry and that of folia, Fissoelphidium became comparable with the Maastrichtian-Paleocene genus Laffitteina Marie. A radial network of infolded folia builds the umbilical ornamentation of Fissoelphidium. After these thoughts, the suprageneric position of F. operculiferum is out from the family Miscellaneidae and considered under Cuvillierinidae (subfamily Laffitteininae). The associated lamellar perforate benthic Foraminifera, including rotaloideans, from the studied Tarbur Formation outcrops are here illustrated and commented. Although most of them remain under open nomenclature, they could be critical to characterize the dispersal of fauna between the Mediterranean Tethys and the Middle East domain, evidencing their paleobiogeographic as well as the possible biostratigraphic importance.

The new crustacean microcoprolite Broennimannia persica n. ichnogen., n. ichnosp., is described from the Paleocene (Danian-Selandian) of eastern Iran. The new microcoprolite is characterized by a bilateral symmetrical system of longitudinal “canals” that in transverse sections display an irregular (labyrinthine) outline with concave infoldings and rounded protuberances. The crescentic outline of parts of the canal system recalls the long-ranging ichnogenus Palaxius Bronnimann & Norton (Carboniferous to Pleistocene). In the latter ichnogenus, however, the canals are isolated. A general determination key for microcoprolites in transverse section is provided. The new microcoprolite occurs in poorly sorted foram-algal grainstones/packstones with a fine-grained siliciclastic content. The associated microfauna and –flora includes common miliolids, among the agglutinating Haymanella, Stomatorbina sp., serpulids, and dasycladalean algae (Cymopolia sp., Trinocladus atacis Segonzac). From Iran, fossil microcoprolites have been described so far only from the Upper Jurassic, Lower Cretaceous, and Miocene. Broennimannia persica represents the first Paleocene record from this area.

The shell architecture of the benthic foraminifera Elphidiella multiscissurata Smout 1955 has been reviewed using material from Tarbur formation in Zagros Mountains isochronous to the type-level in Qatar (Borehole; Maastrichtian of Jebel Dukhan). Characterized by planispiral geometry and wide canaliculate umbilical plugs, the Middle-East species multiscissurata is removed from the Cenozoic genus Elphidiella Cushman 1936 (type species Polystomella artica Parker and Jones) and attributed to Palaeoelphidium gen. nov. In the new genus, spiral umbilical canals border the umbilical plugs. The spiral umbilical canal is constrained between the umbilical plate, folium and the adjacent coil and is produced by the fusion of consecutive foliar chamberlets. Vertical canals pierce the umbilical plug, thus producing communication with the spiral canals and the intraseptal interlocular spaces. Massive ponticuli lie on chamber sutures, nevertheless no retral process were defined in Smout's original description nor seen in the thin sections at our disposition. These characters place the species Palaeoelphidium multisciussuratum gen. nov. within the family Elphidiellidae at the base of the Elphidiids (sensu lato) architecture as the oldest representative of the group. The stratigraphic range of P. multiscissuratum is constrained into the Maastrichtian and its palaeogeography circumscribed to the central-eastern part of the Arabian plate (Qatar, Iraq and Zagros mountains in Iran).

The poorly known dasycladalean alga Cymopolia eochoristosporica Elliott, 1968 is reported for the first time from the upper part of the Tarbur Formation (Zagros Zone, SW Iran) assigned to a late Maastrichtian age. It was reported so far from the Maastrichtian Aruma Formation of Saudi Arabia (type-locality), the Maastrichtian Simsima Formation of Oman, and the Maastrichtian (e.g., Zongshan Formation) of Tibet. All these Maastrichtian occurrences belong to the southern Tethyan margin, with special concentration within the Arabian plate, evidencing its palaeobiogeographic as well as biostratigraphic importance. C. eochoristosporica occurs in algal-foraminiferan wackestones together with other dasycladaleans (e.g., Salpingoporella pasmanica Radoicic) and halimedaceans, benthic foraminifera (Broeckina, Tarburina, Laffiteina, Gyroconulina, Loftusia, Omphalocyclus), rudists, gastropods, as well as corals. As a peculiarity, the calcification of the alga is made up of light-brownish calcite, presumably replacement of the original aragonitic composition. The dasyclad-bearing deposits are assigned to an internal infralittoral, possibly polyhaline depositional setting.

The new dasycladalean alga Dissocladella compressa is described from the lower part of the Tarbur Formation of SW Iran (Zagros Zone). The medium-sized representative of the genus is characterized by rather large primaries displaying slight vertical compression. It occurs in a foraminiferan-algal packstone associated with larger benthic foraminifera typically Omphalocyclus macroporus Lamarck, Loftusia sp., Siderolites cf. calcitrapoides Lamarck, and scattered corals. Associated algae include Trinocladus tripolitanus Raineri, Thyrsoporella longa Radoicic, Ovulites delicatula Elliott, accessory udoteaceans, and corallinaceans.

The species Salpingoporella arumaensis Okla, 1995 was so far only reported from its type-locality, the Campanian?-Maastrichtian of Saudi Arabia. It is here reported for the first time from the upper Maastrichtian of the Tarbur Formation, Zagros Zone, SW Iran. It is taxonomically discussed and with some reservation newly combined as Zittelina? arumaensis (Okla). Suppiluliumaella tarburensis n. sp. is a small to medium-sized species of the genus characterized by a comparably small number of close-set laterals of two orders typical for the genus. It represents the youngest representative of the genus described so far. The new discoveries contribute to a better knowledge of the so far poorly known microflora of the Tarbur Formation of Iran. Z.? arumaensis might be an endemic taxon like Pseudocymopolia anadyomenea (Elliott) or Cymopolia eochoristosporica Elliott, restricted to the Arabian Plate and Tibet.

Pianella turgida , originally described from Cenomanian limestones of the external Dinarids, was subsequently transferred to the genus Salpingoporella . In the middle of the last century, Varma described the genus Morelletpora with Morelletpora nammalensis as type species from the Paleocene of India. Varma considered the new alga to be articulated, with club-shaped segments and only first order laterals. This foundation of Morelletpora was questioned for a long time. Attribution of a second species to Morelletpora , Morelletpora dienii , from the uppermost Cretaceous of southern Italy by Parente, reopened discussion of the genus. Subsequently, Barattolo attributed Salpingoporella turgida to Morelletpora , as Morelletpora turgida nov. comb., and considered the species as being “structurally similar to M. dienii ”. Recent studies of Lower Cretaceous deposits from Iran revealed the existence of numerous, well-preserved specimens of Morelletpora turgida in the upper Barremian-Aptian Taft Formation of the Ardekan–Hersisht and Anarak areas of central Iran. These specimens allow a thorough morphological re-description of this alga and provide clear evidence for both the segmented character of the thallus and the characteristic shape of the laterals. These new data reinforce the assignment of this alga to Morelletpora , adding observations that support emendation of the diagnosis. Morelletpora turgida has been identified in limestones of Barremian-Cenomanian age from numerous regions representing the southern and central part of the Tethyan Domain.

We describe a new Maastrichtian species of the benthic foraminifer Elazigina siderea from Tarbur Formation. Its main characters are the presence of heavy feathered umbilical sutures, a wide umbilical plug, and umbilical piles. This species, formerly reported from Turkey as Smoutina cruysi, constitutes the oldest known record of the genus Elazigina. Elazigina siderea sp. nov. comes from the Arabian domain and its presence is probably related to the migration of the Cretaceous foraminifer Orbitokathina. Prior to this study, the oldest representatives of this genus were only known from the Paleocene. Therefore, the presence of the new taxon in the Maastrichtian suggests the genus Elazigina passed the Cretaceous–Paleogene boundary, and survived to the environmental crisis associated with a great biosphere mass extinction that wiped out most of the Late Cretaceous larger foraminifers. This is supported by shell features displayed by Elazigina siderea sp. nov., interpreted as adaptation to thrive under elevated trophic levels, like the species of another benthic foraminifer Laffitteina.

Anew larger benthic porcelaneous foraminifer of soritid affinity is described as Tarburina zagrosiana n. gen., n. sp. from the late Maastrichtian of the Tarbur Formation, Zagros Zone, SW Iran. It occurs in foraminiferal–dasycladalean wackestones and packstones, in association with Loftusia ssp., dicyclinids/cuneolinids, Neobalkhania bignoti Cherchi & Schroeder, Gyroconulina columellifera Schroeder & Darmoian, Spirolina? farsiana Schlagintweit & Rashidi, Broeckina cf. dufrenoyi (d’Archiac), other benthic foraminifers, and dasycladalean algae. Due to its elongate test and marginal chamber subdivision by aligned vertical partitions, Tarburina n. gen. can be compared with representatives of the Praerhapydionininae. The interio-marginal slit-like foramina/aperture of Tarburina represents an outstanding feature in complex porcelaneous taxa. The monospecific genus Tarburina is considered a Maastrichtian newcomer within the Late Cretaceous Global Community Maturation cycle of larger benthic foraminifera. A biostratigraphic and palaeobiogeographical restriction seems possible, as reported for many other Late Cretaceous larger benthic foraminifera.