Integrated biostratigraphy based on planktonic foraminifera and dinoflagellates across the Cretaceous/Paleogene (K/Pg) transition at the Izeh section (SW Iran)

The present work is based on semi-quantitative study carried on detailed sampling (samples are spaced by 5, 10 and 15 cm close to the boundary) of an essentially continuous and expanded section crossing the Cretaceous–Paleogene (K/Pg) boundary in Iran. By this work, we attempt to detail biostratigraphy based on planktonic foraminifera biozones and correlate biozones and subzones with dinocyst events. The entire Cretaceous–Paleogene interval contains rich, diversified and well-preserved planktonic foraminifera and dinoflagellate cyst assemblages. Four planktonic foraminiferal biozones have been recognized across the Cretaceous–Paleogene transition (K/Pg): Abathomphalus mayaroensis Biozone including Plummerita hantkeninoides Subzone from the Late Maastrichtian and Guembelitria cretacea (including Hedbergella holmdelensis and Parvularugoglobigerina longiapertura subzones), Parvularugoglobigerina eugubina Biozone and Parasubbotina pseudobulloides Biozone belonging to the Early Danian. These biozones have been correlated with four dinocyst biozones: the Manumiella seelandica Biozone belonging to the Late Maastrichtian and the Alisocysta reticulata, Senoniasphaera inornata and Damassadinium californicum biozones from the Early Danian. At this section, like at the El Kef section (GSSP for the K/Pg) and the auxiliary sections, an Ir anomaly is detected indicating the K/Pg boundary. This geochemical anomaly coincides also with mass extinctions of planktonic foraminifera species. The extinct species are in particular the large, complex tropical and subtropical taxa dwelling in subsurface and lower photic water. The mass extinctions at the Izeh section occurred over a succinct period of time similar to the K/Pg type section at El Kef (Tunisia). These sudden mass extinctions indicate a catastrophic pattern event occurring at the Maastrichtian/Danian boundary. In contrast the organic-walled dinocysts were less affected by the mass extinction and most species crossed the K/Pg boundary without showing mass and sudden extinctions. Nevertheless, they showed changes in their assemblages’ structure beyond the K/Pg boundary. Especially, Manumiella seelandica and M. druggii, typical species of Antarctic Maastrichtian dinocysts assemblages, occur in coeval deposits at the Izeh section; they persist through the Lower Danian and, like in Tunisia (e.g., El Kef section, Ellès section) show an obvious increase in relative abundance.     

Revision of the foraminiferal biozonation scheme in Upper Cretaceous carbonates of the Dezful Embayment,Zagros, Iran: Integrated palaeontological,sedimentological and geochemical investigation

Cretaceous carbonate successions of the Bangestan Group, such as the Sarvak and Ilam formations, are among the most prolific hydrocarbon reserves of the Middle East. However, relatively little is known about their detailed palaeontology and biostratigraphy. Moreover, due to lithological similarity of these carbonate formations recognition of their boundaries in subsurface studies is problematic. To investigate these units, biostratigraphic analyses were carried out on nearly 1100 m of cores, including core plug samples and thin sections prepared from five giant and supergiant oilfields in the northern and southern Dezful Embayment, SW Iran. Accordingly, 59 species of foraminifera (assigned to 43 genera) as well as 11 species of non-foraminifera (10 genera) were recognized. As a result, three biozones were identified, which in stratigraphic order are: Nezzazata-Alveolinids Assemblage Zone; Moncharmontia apenninica-Nezzazatinella-Dicyclina Assemblage Zone; and Rotalia skourensis-algae Assemblage Zone. These are compared with the Wynd's (1965) biozonation scheme, previously introduced in the Zagros area, and a revised scheme is presented. Accordingly, a Cenomanian–Turonian age and a Coniacian–Campanian age are envisaged for the Upper Sarvak and Ilam formations, respectively. In our new biostratigraphic scheme, the Sarvak–Ilam formations boundary is considered to be located above the Moncharmontia apenninica-Nezzazatinella-Dicyclina Assemblage Zone (equivalent of Valvulammina-Dicyclina Assemblage Zone of Wynd, 1965), that is Turonian in age. This zone is bounded by two palaeoexposure surfaces, which correspond approximately to the C–T boundary transitional interval and a post-Turonian, which can be possibly assigned to the Coniacian. Significant sedimentological features of these disconformities include bauxitic–lateritic horizons, karstified profiles and solution-collapsed breccias. Geochemical signatures of these meteorically altered surfaces are also considered to calibrate biofacies and biozones. Finally, we compared our new biozonation scheme with other studies in neighboring areas of SW Iran and the Middle East.     

伊朗八种跳小蜂及一新种记述（膜翅目：小蜂总科）

报道由伊朗设拉子大学农学院采集饲出的与林木害虫有关的７属８种寄生蜂,它们均属膜翅目小蜂总科、跳小蜂科,扬与林木介壳虫有关的Ａｎａｇｙｒｕｓ ｐｓｅｕｄｏｃｏｃｃｉ,Ｃｈｅｉｌｏｎｅｒｒｕｓ ｃｅｒｏｐｌａｓｉｔｓ,Ｄｕｓｍｅｔｉａ ｆａｓｃｉｐｅｎｎｉｓ,Ｈｏｍａｌｏｔｙｌｕｓ ｅｐｈｉｐｐｉｕｍ,与草蛉有关的Ｉｓｏｄｒｏｍｕｓ ａｔｒｉｖｅｎｔｒｉｓ,Ｉｓｏｄｒｍｕｓ ｃｏｌｌｉｍａｃｕｌａｔｕ     

Ichnology and sedimentology of a tide‐influenced delta in the Ordovician from the northeastern Alborz range of Iran (Kopet Dagh region)

The Middle–Late Ordovician Ghelli Formation in the Kopet Dagh region northeastern Alborz range of Iran is composed of siliciclastic rocks deposited in a variety of turbidite to marginal marine environments (deep marine clastic fan and related environments and prodelta, distal delta front, proximal delta front and distributary channels). The ichnology of the middle member of the Ghelli Formation is here reported. Combined sedimentological and ichnological analysis allows recognition of a tide‐influenced deltaic succession in the middle member of the Ghelli Formation consisting of three main facies associations: lower distributary channels, delta front and prodelta facies. Twenty‐two ichnogenera have been identified in this marginal marine succession: Arenicolites, Arthrophycus, Bergaueria, Chondrites, Conichnus, Cruziana, Cylindrichnus, Didymaulichnus, Diplichnites, Diplocraterion, Helminthopsis, Gyrochorte, Lockeia, Macaronichnus, Monomorphichnus, Palaeophycus, Planolites, Rosselia, Rusophcus, Skolithos, Teichichnus and ?Scolicia. Their distribution is clearly linked with lithofacies and depositional palaeoenvironments. The ichnological analysis reveals that the trace fossil suites developed in these environments indicate low diversity and low to moderate abundance of burrows, poor development of tiering and sporadic distribution. Low ichnodiversity and low bioturbation intensities with higher bioturbation clusters consist of facies‐crossing ichnogenera, and the impoverishment of suspension‐feeding trophic types indicates ‘stressed’, non‐archetypal expression of the Cruziana ichnofacies. The periodic higher intensities of bioturbation due to variations in hydrodynamic regimes of tidal currents reflect the archetypal of the Cruziana ichnofacies (and rare Skolithos ichnofacies).     

New bivalves from the Jurassic of Iran

Three new subgenera, Gervillaria (Platygervillaria), Isognomon (Iranognomon), and Mytilaster (Persiaster), and seven new species, Gervillaria (Platygervillaria) alifera, Isognomon (Iranognomon) arkelli, Inoperna (Inoperna) striata, Mytilaster (Persiaster) ancestralis, Astarte persipulla, Orthotrigonia fazli, and Gissaromya abramovi, from the Jurassic of Iran are described.     

Complete Genome Sequence and Genome Analysis of Eggplant mottled dwarf virus‐Iranian Isolate

The full‐length nucleotide sequence of the Iranian isolate of Eggplant mottled dwarf virus (EMDV), a phytorhabdovirus, was determined using the random polymerase chain reaction method (rPCR) followed by PCR with specific primers to fill in the gaps. The negative‐sense RNA genome of the Iranian isolate of EMDV contains 13154 nucleotides and seven open‐reading frames (ORFs) in the order 3′‐leader‐N‐X‐P‐Y‐M‐G‐L‐trailer‐5′. These ORFs encode the nucleocapsid, X protein (of unknown function), phosphoprotein, Y protein (putative movement protein), matrix protein, glycoprotein and RNA‐dependent RNA polymerase, respectively. EMDV has a 199 nt 3′ leader RNA and a 151 nt 5′ trailer, and the ORFs are separated by conserved intergenic sequences. Phylogenetic analyses indicate that EMDV is most closely related to Potato yellow dwarf virus, which has a distinctly different geographical distribution.     

Eucoptocnemis tischendorfi (Püngeler) (Lepidoptera: Noctuidae: Noctuinae): New record for Iran with description of female of Brachygalea miskoi Ronkay (Lepidoptera: Noctuidae: Oncocnemidinae)

A noctuid species, Eucoptocnemis tischendorfi (Püngeler, 1915) (Lepidoptera: Noctuidae), is first reported for the fauna of Iran and the female of Brachygalea miskoi Ronkay, 1997 is first described. Adults including genitalia of both species are illustrated.     

An improved estimation of daily clear-sky biologically EER from broadband global solar radiation

To establish a relation between biologically effective erythemal radiation (EER) and global solar radiation, the hourly and daily clear-sky broadband (310–2,800 nm) global solar radiation (G) and spectral ultraviolet radiation incident on a horizontal surface at Esfahan, Iran (32°37′N, 51°40′E) were measured during the period 2001–2005. Good correlations at statistically significant levels between the daily values of EER and the daily G were found. The seasonal variability of EER/G is also discussed and the correction factors are determined for inclusion of vertical column ozone and solar zenith angle (SZA) cycles. The comparison of the estimated daily EER against the independent observed EER revealed that under clear sky conditions the estimations are accurate to 10% or better over SZA of 10–60° and column ozone of 250–350 Dobson. The comparison of the results with the similar works that have used shorter period of experimental data showed more accurate estimates. The deduced relations could be used to a rough estimate of the daily EER from G in arid climate regions, where there is no measured UV radiation or there are instrumental and other difficulties encountered in measuring UV radiation.