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The radiological risks to the Tohoku hynobiid salamanders (class Amphibia), Hynobius lichenatus due to the Fukushima Dai-ichi Nuclear Power Plant accident were assessed in Fukushima Prefecture, including evacuation areas. Aquatic egg clutches (n = 1 for each sampling date and site; n = 4 in total), overwintering larvae (n = 1-5 for each sampling date and site; n = 17 in total), and terrestrial juveniles or adults (n = 1 or 3 for each sampling date and site; n = 12 in total) of H. lichenatus were collected from the end of April 2011 to April 2013. Environmental media such as litter (n = 1-5 for each sampling date and site; n = 30 in total), soil (n = 1-8 for each sampling date and site; n = 31 in total), water (n = 1 for each sampling date and site; n = 17 in total), and sediment (n = 1 for each sampling date and site; n = 17 in total) were also collected. Activity concentrations of (134)Cs + (137)Cs were 1.9-2800, 0.13-320, and 0.51-220 kBq (dry kg) (-1) in the litter, soil, and sediment samples, respectively, and were 0.31-220 and0.29-40 kBq (wet kg)(-1) in the adult and larval salamanders, respectively. External and internal absorbed dose rates to H. lichenatus were calculated from these activity concentration data, using the ERICA Assessment Tool methodology. External dose rates were also measured in situ with glass dosimeters. There was agreement within a factor of 2 between the calculated and measured external dose rates. In the most severely contaminated habitat of this salamander, a northern part of Abukuma Mountains, the highest total dose rates were estimated to be 50 and 15 μGy h(-1) for the adults and overwintering larvae, respectively. Growth and survival of H. lichenatus was not affected at a dose rate of up to 490 μGy h(-1) in the previous laboratory chronic gamma-irradiation experiment, and thus growth and survival of this salamander would not be affected, even in the most severely contaminated habitat in Fukushima Prefecture. However, further studies of the adult salamanders may be required in order to examine whether the most severe radioactive contamination has any effects on sensitive endpoints, since the estimated highest dose rate to the adults exceeded some of the guidance dose rates proposed by various organisations and programmes for the protection of amphibians, which range from 4 to 400 μGy h(-1). Conversely, at one site in Nakadori, a moderately contaminated region in Fukushima Prefecture, the dose rate to the adult salamanders in spring of 2012 was estimated to be 0.2 μGy h(-1). Estimated dose rates to the overwintering larvae in spring of 2012 were 1 and 0.2 μGy h(-1) at one site in Nakadori, and in Aizu, a less contaminated region in Fukushima Prefecture, respectively. These results suggest that there is a low risk that H. lichenatus will be affected by radioactive contamination in these districts, though further studies on dose rate estimation are required for definitive risk characterisation.

Arisaema tosaense Makino develops either 1 or 2 leaves during both the male and female phases. To clarify the relationship between growth stage (sexual stage) and leaf number in this species, we conducted morphological analysis using A. tosaense, A. japonicum Bulme, A. sikokianum French. & Sav., and A. ringens (Thunb.) Schott. We found that increase in size of pseudostem of these Arisaema species is correlated to changes in the growth stage from sterile to male and from male to female phases. In particular, 1-leaf individuals of A. tosaense appeared at the beginning of both male and female phases, suggesting that they contribute to the earlier appearance of the fertile phase from sterile stages

Pilophorus typicus (Distant) (Heteroptera: Miridae) is a predatory bug occurring in East, Southeast, and South Asia. Because the active stages of P. typicus prey on various agricultural pest insects and mites, this species is a candidate insect as an indigenous natural enemy for use in biological control programs. However, the mass releasing of introduced natural enemies into agricultural fields may incur the risk of affecting the genetic integrity of species through hybridization with a local population. To clarify the genetic characteristics of the Japanese populations of P. typicus two portions of the mitochondrial DNA, the cytochrome oxidase subunit I (COI) (534 bp) and the cytochrome B (cytB) (217 bp) genes, were sequenced for 64 individuals collected from 55 localities in a wide range of Japan. Totals of 18 and 10 haplotypes were identified for the COI and cytB sequences, respectively (25 haplotypes over regions). Phylogenetic analysis using the maximum likelihood method revealed the existence of two genetically distinct groups in P. typicus in Japan. These groups were distributed in different geographic ranges: one occurred mainly from the Pacific coastal areas of the Kii Peninsula, the Shikoku Island, and the Ryukyu Islands; whereas the other occurred from the northern Kyushu district to the Kanto and Hokuriku districts of mainland Japan. However, both haplotypes were found in a single locality of the southern coast of the Shikoku Island. COI phylogeny incorporating other Pilophorus species revealed that these groups were only recently differentiated. Therefore, use of a certain population of P. typicus across its distribution range should be done with caution because genetic hybridization may occur.

Morphologically putative introgressive hybrids of Arisaema sikokianum Franch. et Sav. and A. tosaense Makino were newly found in Kochi and Tokushima Prefectures in Japan. All the individuals have the same morphological characteristics as A. tosaense excluding a purple spathe. Molecular analysis using PCR-RFLP of internal transcribed spacer (ITS) in nuclear DNA (nrDNA) indicates that these putative introgressive hybrids have the same pattern as A. tosaense. Moreover, the sequences of chloroplast DNA (cpDNA) of the putative introgressive hybrids were identical to A. sikokianum from Kochi Prefecture and A. tosaense from Tokushima Prefecture. The results suggest that the plants are introgressive hybrids of A. sikokianum and A. tosaense and that they have highly exchanged genes with A. tosaense.

Although earthworms are hermaphroditic animals with biparental sexual reproduction, some parthenogenetic species have been found. Evolutionary trends in parthenogenetic earthworms revealed a reduction in the reproductive organs. To clarify the phylogenetic relationships of parthenogenetic earthworms with different degree of degraded reproductive organs, we conducted a morphological analysis of the reproductive organs and molecular phylogenetic analyses of Amynthas vittatus which usually degraded a part of reproductive organs. Morphological analysis revealed that almost all individuals collected around Mt. Aobayama, Sendai city of northeastern Japan, possessed male pores, while individuals collected from areas located across Hirose River did not. Phylogenetic analysis using mitochondrial DNA sequences of 48 individuals representing 20 populations indicated that almost all individuals collected around Mt. Aobayama belonged to a different lineage from the other populations collected around Sendai, and that almost all individuals collected from across Japan belonged to the latter lineage. We suggest that the difference in the male pore possession rate was caused by histories of each population, but the A. vittatus population found on Mt. Aobayama belongs to a different lineage as compared to the other Japanese populations and not the primitive population. Thus, the parthenogenetic earthworm A. vittatus has undergone at least two morphological evolutionary processes.

To describe the phylogeographic structures of Asparagus schoberioides Kunth (Asparagaceae) in Japan, we investigated its nucleotide sequence variations with respect to its geographic distribution pattern. Sequencing of the internal transcribed spacer (ITS) 1 region in 29 samples of A. schoberioides revealed 20 polymorphic nucleotide sites. As a result, the 29 samples of A. schoberioides fell into 15 distinct haplotypes and phylogenetic analyses revealed these haplotypes fell into two major clades, Clade 1 and Clade 2. The haplotypes of Clade 1 were distributed chiefly along the Pacific Ocean side of Japan, while those of Clade 2 occurred mainly along the Japan Sea side. This result suggests that A. schoberioides has migrated via two routes in Japan.

To determine the eVolutionary history of Asparagus cochinchinensis (Asparagaceae), we investigated the geographic pattern of its nucleotide sequence variations in Japan, Taiwan, South Korea and China. We found 21 polymorphic nucleotide sites by sequencing the internal transcribed spacer (ITS) region, which gave rise to a total of 15 haplotypes, labeled A to O. The A-type was found only in inland China (Guizhou and Sichuan), and the other haplotypes in China extended to several lineages; therefore, A. cochinchinensis may have its origin in the interior of China. The I-type has large distribution area and it also experienced a quick expansion in relative recent years. Haplotype differentiation was observed between the eastern and western side of the Central Mountain Ridge in Taiwan. Two lineages were found in Japan, one in the Yaeyama Islands and the other in remaining areas of Japan, implying that A. cochinchinensis independently colonized in Japan at least twice.

A morphologically intermediate plant between Arisaema sikokianum Franch. et Sav. and A. serratum (Thunb.) Schott has been newly found in Kochi Prefecture, Shikoku, Japan. The putative hybrid has the intermediate morphological characteristics of the parental species. Molecular analysis using PCR-RFLP of internal transcribed spacer (ITS) in nuclear DNA (nrDNA) indicates that the putative hybrid has a combined pattern of the two putative parent species. Moreover, the sequence result of chloroplast DNA (cpDNA) of the putative hybrid was identical to that of A. sikokianum. These results suggest that the putative hybrid is a hybrid between A. sikokianum and A. serratum and that it was formed by interactive gene exchanging via pollens from A. serratum to A. sikokianum. It is the first record of a hybrid between A. sikokianum and A. serratum.

"Supplemental Table 1" in the 23rd line from the top in the right column on the 32nd page should be replaced with "Table 5".