Cadmium and lead accumulation in three endogeic earthworm species.

The objective of this study was to assess the capability of earthworms from the same ecological group as heavy metal bioindicators. Three earthworm species from the endogeic group were studied: Aporrectodea caliginosa (Savigny, 1826), Perelia kaznakovi (Michaelsen, 1910) and Octolasion lacteum (Örley, 1885). Their accumulation of the heavy metals lead (Pb) and cadmium (Cd) were studied from three stations in Tehran province, Iran. O. lacteum was used to compare metal accumulations in two sites located next to a highway. A. caliginosa and P. kaznakovi were used at a third site located near the edge of a sewage system to compare metal accumulations between the two endogeic species in this area. At both locations, the concentrations of Cd and Pb in earthworms were higher than in the surrounding soil. The results of the study revealed that P. kaznakovi and A. caliginosa were better bioindicators for Pb, but O. lacteum was a better bioindicator for Cd. These earthworms can therefore be used as Cd and Pb bioindicators in environmental assessment.

New earthworm records from the Caspian Hyrcanian Forests of Iran (Oligochaeta: Megadrili).

Earthworms are the most important soil invertebrates worldwide, in terms of biomass and effects on soil processes. In this study, 21 earthworm species, including four new records were identified from Caspian Hyrcanian Forests (North of Iran). Four species; Criodrilus lacuum, Lumbricus rubellus, Metaphire californica, and Octodrilus transpadanus and the family Criodrilidae are reported for the first time. Previous studies have identified 31 earthworm species belonging to 14 genera and three families (Lumbricidae, Acanthodrilidae, and Megascolecidae) in Iran; therefore, these new records increase the number of earthworm species to a total of 35.

Reproduction of Limnatis paluda (Tennent 1859) in laboratory conditions.

The reproductive functions of Limnatis paluda were studied in laboratory conditions including imposing of two thermal conditions (T1: 18 ± 2 °C and T2: 26 ± 2 °C) and with there being placement of three bedding substrates (tile, moss, and stone) in the containers specimens were confined. Furthermore, values for reproductive variables of cocoons and hatchlings were recorded. With the T2 treatment, gravid adults had cocoon depositions, whereas those when there was imposing of the T1 treatment did not have cocoon depositions. There was cocoon deposition only on the moss bedding, and it is presumed that moss could provide a robust and stable nursing microenvironment for developing embryos. Frequency (%) of cocoon depositions did not vary during the months of the deposition period. Hatching occurred after 26 ± 2 days when there was imposing of the T2 treatment. There was no correlation between the values for size of the ovigerous cocoons and number of offspring. There was a negative correlation between number and mean weight of hatchlings. There was a difference in cocoon weight for the different months and fluctuation in mortality and hatching rate which is assumed to be related to differences in feeding behaviors.

Integrative taxonomy of some Iranian peregrine earthworm species using morphology and barcoding (Annelida: Megadrili).

Despite the biological and economic importance of earthworms, the taxonomic status and evolutionary relationships of most lumbricid genera are still under debate. Further complications arise from the recognition that earthworms also show a high cryptic diversity. Past and current field studies of Iranian earthworm fauna have resulted in the identification of a total number of 28 earthworm species. However, many specimens do not fully fit into their original descriptions, making the species assignation very difficult. In this study, we evaluated the genetic diversity using mitochondrial markers as a tool to assess the species occurrence of some problematic species in Iran. Four species with high morphological variation were selected: Aporrectodea caliginosa (Savigny, 1826), Aporrectodea trapezoides (Dugès, 1828), Dendrobaena byblica (Rosa, 1893) and Dendrobaena veneta (Rosa, 1886). Morphological identification was contrasted with the molecular information generated through COI and 16S barcoding and the COI and 16S sequences stored in the Genbank. The results of this first integrative taxonomic analysis revealed that D. veneta consisted of two separated clades and that a number of species assigned to D. byblica showed very close relationships with those belonging to the genus Philomontanus. The lack of taxonomic expertise and identification characters providing a clear and unambiguous identification of earthworms highlights the urgent need of new tools to identify species unequivocally. Therefore, it is concluded that more taxonomical studies are needed to clarify the diagnostic characters and taxonomic status of the species belonging to two genera, Aporrectodea and Dendrobaena (Lumbricidae), in Iran.

Resurrection of the earthworm species Dendrobaena fedtschenkoi (Michaelsen, 1900), a former synonym of Dendrobaena byblica (Rosa, 1893) (Clitellata: Megadrili).

Dendrobaena byblica (Rosa, 1893) is a Circum-Mediterranean earthworm species complex containing more than a dozen synonymous names. From these, only two species have been resurrected so far, D. ganglbaueri (Rosa, 1894) and Fitzingeria annectens (Rosa, 1895). Here we demonstrate that Dendrobaena fedtschenkoi (Michaelsen, 1900) described from the Pamir Mts. Tajikistan differs from D. byblica both in morphological and molecular features, and represents an independent species.

Comparative studies on reproductive traits of natural populations of Eisenia andrei Bouché, 1972 from Zagros Mountain, Iran (Annelida: Oligochaeta).

Comparative studies were carried out on growth and reproduction patterns of eight populations of Eisenia andrei (Bouché, 1972) from different parts of western Iran along the Zagros Mountains, considered to lie within the natural range of this species. Parameters were gain in body weight, number of cocoon production, hatching success, number of hatchlings, hatchlings growth and survival. There were significant differences in mean numbers of viable cocoons, incubation time, reproductive rate, growth rate and final weight between different populations. The resulting groupings did only partially coincide with genetic clusters established in a previous study. It is nonetheless suggested to include life cycle parameters as an additional set of data to understand the micro-taxonomic structure of variable species.

Review of the Eisenia muganiensis (Michaelsen, 1910) species group with description of two new species (Oligochaeta: Lumbricidae).

The Eisenia muganiensis species group is established, consisting of a set of Asian earthworm species characterized by elongate, backward placed clitellum and tubercles: Eisenia malevici Perel, 1962; Eisenia muganiensis (Michaelsen, 1910); Eisenia patriciae Szederjesi, Pavlícek, Coskun & Csuzdi, 2014 and Eisenia transcaucasica (Perel, 1967). The species are shortly reviewed and furthermore, two new species of the E. muganiensis group are described, E. kontschani sp. nov. from Turkey and E. malekae sp. nov. from Iran.