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A New Species in the Marphysa sanguinea Complex (Annelida, Eunicidae) from Hong Kong

Marphysa hongkongensa n. sp. (Annelida: Eunicidae) is described based on samples from the intertidal zone of Tolo Harbour, Hong Kong. This new species belongs to the Marphysa sanguinea species complex. It is characterized by a subacicular hook from chaetiger 26-58 to the posterior end, branchiae with up to 5-10 filaments from chaetiger 14-35 to the posterior end, and four types of pectinate chaetae. Molecular analyses indicated that the cytochrome oxidase c subunit I gene and 16S RNA gene of Marphysa hongkongensa diverged from the corresponding sequence of the closest related species of Marphysa in GenBank by 19.5% and 12.1%, respectively. An identification key is provided for species in the Marphysa sanguinea complex along the Chinese coast.

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Effects of Greenfall on Ground-dwelling Arthropods in a Subtropical Forest

Resource events such as typhoon-triggered greenfall have consequences for multiple ecological mechanisms, ranging from population dynamics and trophic interactions to ecosystem processes. Arthropods are sensitive to environmental disturbances, and many taxa have been used as indicator species. In a field experiment, we tested the effects of greenfall on ground-dwelling arthropods (mostly litter-dwelling taxa) in a forest of Taiwan red pine (Pinus taiwanensis) in the summer of 2013. Of 20 field plots (5 × 5 m), half received P. taiwanensis greenfall while the other half served as unaltered controls. As predicted, some arthropod taxa responded more strongly than others to the greenfall addition. Among the examined arthropod taxa (Araneae, Coleoptera: Carabidae, Coleoptera: Staphylinidae, Hymenoptera: Formicidae, Collembola, Isopoda: Oniscidea), the predatory staphylid beetles (Staphylinidae) responded positively to greenfall addition while the larger-sized detritivore woodlice (Oniscidea) responded negatively. Contrary to our prediction of a positive response, the smaller-sized detritivore springtails (Collembola) were unaffected by the greenfall addition. At the beginning of this study, we observed short-term effects of a naturally-occurring typhoon, to which springtails and ants (Formicidae) responded negatively while staphylid beetles responded positively. Also contrary to our prediction, these taxon-specific responses did not suffice to alter the composition of arthropod communities. We concluded that the intra-annual effects of typhoons-specifically those associated with greenfall-are more likely to impact certain taxa, including staphylid beetles, woodlice, springtails and ants. At the taxonomic level examined here, these intra-annual effects on community composition are non-detectable. As typhoon frequency and intensity are likely to change with global warming, the study makes a timely contribution to our understanding of typhoon-induced ecological dynamics in subtropical plantation forests.

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Hormonal Regulation of Testicular Development in the Finless Porpoise Neophocaena asiaeorientalis sunameri: Preliminary Evidence from Testicular Histology and Immunohistochemistry

Sex hormones play a crucial role in regulating testicular development and maintaining spermatogenesis in the male reproductive system. Knowledge of hormonal regulation in odontocetes is limited to captive species. In this study, the characteristics of hormonal regulation during the testicular development were assessed by histological and immunohistochemical methods in the East Asian finless porpoise (Neophocaena asiaeorientalis sunameri), native to the Chinese Yellow/Bohai Sea coast, China. The testes mass, seminiferous tubule cross section diameter, thickness of the tunica albuginea, and the level of testosterone (T) expression increased abruptly at the age of 3-3.5 years (body length 140-145 cm). However, the estradiol (E_2) expression level decreased with age after 3 years. Therefore, we inferred that the male East Asian finless porpoise (EAFP) ＞ 3 years old (body length ＞ 140 cm) could be classified as the age of puberty onset. Immuno-localization with T was only observed in the interstitial fluid of all animals at all ages. In contrast, a positive reaction for E_2 and its receptor could be observed in the Leydig, myoid, Sertoli, and germ cells at different developmental stages. T is presumed to maintain the tubular microenvironment for spermatogenesis while E_2 may directly regulate spermatogenesis at the level of germ cells. Our findings provide useful information for understanding reproductive status and hormonal regulation in the male EAFP.

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Swimbladder Evolution of Longfin Herrings (Pristigasteridae, Teleostei)

Longfin herrings form a monophyletic, circumtropically distributed family of mostly marine teleost fishes, the Pristigasteridae (Clupeoidei), that includes 38 species classified into nine genera and three main lineages (the Pelloninae, Pristigasterinae, and the genus Ilisha). The external morphology and osteology of the Pristigasteridae provide only a few, sometimes conflicting, informative characters which makes it difficult to reconstruct their phylogeny, but their swimbladder (a visceral gas-filled chamber that has several important functions in the Teleostei) appears to be highly specialized and variable among species. In particular, the swimbladder of most Indo-West Pacific pristigasterid species exhibits one or paired post-coelomic extensions, whereas New World species do not. The presence of these extensions conflicts with the current systematic classification, as they are only found in subsets of different taxa. To examine this conflict, the most comprehensive molecular phylogenetic tree of the Pristigasteridae to date was built using six molecular markers and 21 species. This tree deeply disagreed with the current classification in that it indicated that the subfamilies Pelloninae and Pristigasterinae are not monophyletic and neither are the genera Ilisha, Pellona, and Opisthopterus. Using this tree to infer the evolution of the post-coelomic extensions, it was found that their absence is the ancestral condition in the Pristigasteridae. Indo-West Pacific species with post-coelomic extensions evolved later and form a monophyletic group, inside which species with only one extension form a monophyletic group. The consequences of our findings on the evolution and classification of Pristigasteridae are discussed. We suggest that only species of Pristigasteridae having one or paired post-coelomic extensions should be included in the genus Ilisha.

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Postnatal Growth and Vocalization Development in the Long-fingered Bat, Myotis capaccinii (Chiroptera, Vespertilionidae)

We simultaneously monitored postnatal growth and vocalization development in a free living population of the long-fingered bat, Myotis capaccinii, in a maternity colony in the Mahidasht cave, western Iran. Length of forearm and body mass of 1-day-old neonates averaged 19.59 ± 1.23 mm and 3.59 ± 0.23 g and followed linear pattern of growth at mean growth rates of 0.74 mm/day and 0.15 g/day until 28 days of age, after which is increased slowly. A similar nonlinear growth pattern was found for ten wing characteristics (wingspan, wing area, handwing length, handwing area, armwing length, armwing area, aspect ratio, wing loading, tip length ratio, and tip area ratio). However, postnatal growth followed a two phase linear pattern of increase-decrease for the epiphyseal-phalangeal gap and decrease-increase for wing loading. At birth, infant bats produced low, short frequency sonar and oral calls in isolation before they could open their eyes. Isolation calls obtained at age 1-4 days old from M. capaccinii pups were frequency modulated shallow calls with longer duration (7.54 ± 1.83 ms) and lower peak frequency (20.07 ± 0.89 kHz) compared to adult female calls (2.35 ± 0.75 ms and 54.02 ± 4.34 kHz). During days 12-16, calls began to resemble adult echolocation calls. Duration of calls increased slightly before 7 days old and then gradually decreased. The peak, start and end frequencies of spontaneous calls increased with age. When the juvenile bats started foraging outside the cave, they only omitted nasal FM calls with 1-2 harmonics. Comparing postnatal changes in body and wing characteristics with those of vocalization, we found that the most positive correlation was between body (forearm length and body mass) and wing features (wing area, wingspan, handwing area, armwing area and aspect ratio) and call parameters (peak, start and end frequency), while wing loading had a significant negative correlation with the call parameters.

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Variation in the Karyotype, Cytochrome b Gene, and 5S rDNA of Four Thunnus (Perciformes, Scombridae) Tunas

Thunnus tunas in Scombridae are divided into the temperate subgenus Thunnus (bluefin group) and tropical subgenus Neothunnus (yellowfin group) species based on anatomic traits and distributions. The main purpose of this study was to examine the systematic status of T. obesus based on karyotype, cytochrome (Cyt) b gene, and 5S ribosomal DNA sequences. All T. obesus, T. albacares, T. alalunga, and T. orientalis specimens were caught in southeastern coastal waters off the main island of Taiwan. The karyotypical formula of T. obesus was 2 m + 2 st + 44 t, that of T. albacares was 2 m + 2 sm + 2 st + 42 t, that of T. alalunga was 2 m + 2 sm + 2 st + 42 t, and that of T. orientalis was 2 m + 2 sm + 44 t (m: metacentric; sm: submetacentric; st: subtelocentric; t: telocentric chromosome). According to a molecular genetics analysis for these species using Cyt b gene sequences (1141 bp), interspecific genetic distances ranged from 0.004 (T. orientalis vs. T. alalunga) to 0.038 (T. alalunga vs. T. obesus). The genealogy tree exhibited these 4 species as being categorized into 4 monophyletic groups with high bootstrapping values; T. alalunga and T. orientalis are sister species. This result suggests that the species currently allocated in Thunnus and Neothunnus might need new taxonomic characters to redefine the monophyly of the two subgenera. The sequence lengths of all cloned 5S genes from the 4 species ranged from 327-342 bp. Interspecific genetic distances ranged from 0.016 (T. orientalis vs. T. alalunga) to 0.111 (T. orientalis vs. T. albacares). The phylogenetic tree based on 5S rDNA shows T. obesus divided into 2 groups: one similar to T. albacares and the other close to T. orientalis. These results imply that Thunnus tunas have a common synapomorphic character with Scombridae fish (2n = 48) and high numbers of telocentric chromosomes (42-44). Thunnus orientalis and T. alalunga are sister based on molecular data. Thunnus obesus may have been derived from a more-complicated speciation processes.

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Phylogeographical and Morphological Analyses of Triplophysa stenura (Cypriniformes: Nemacheilidae) from the Three Parallel Rivers Region, China

Triplophysa stenura is an indigenous and widely distributed loach in the Qinghai-Tibet plateau and adjacent Three Parallel Rivers region of China. Morphological and phylogenetic analyses were performed in order to explore the genetic and morphological variation in T. stenura populations from different geographic regions and infer the divergence time and relationships between populations from the three rivers (Jinsha River, Nu River and Lancang River). Two mitochondrial genes (Cyt b, D-Loop) and 35 morphological characters were selected for genetic and morphological analyses, respectively. Phylogenetic and network analyses reveal that T. stenura is a single lineage with three well supported clades strictly corresponding to specific river systems. Divergence time analysis suggests that the divergence of T. stenura and formation of the Three Parallel Rivers are closely associated with the Kun-Huang Movement (1.1- 0.6 MYA), which lead to the uplift of the Qinghai-Tibet plateau. AMOVA reveals that there is moderate genetic differentiation among populations. Results from ANOVA suggest that several morphological characters show significant variation among populations and drainages. Descriptive morphological variation (e.g., color pattern) in different populations of T. stenura clarifies a set of characters that can be used to accurately identify members of this group in the future. We conclude that T. stenura has moderate population genetic structure and character variation in this study area and the divergence and evolution of T. stenura is associated with the uplift of the Qinghai-Tibet plateau.

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Seaward Migration Routes of Indigenous Eels, Anguilla japonica, A. marmorata, and A. bicolor pacifica, via Satellite Tags

The spawning migration of the Japanese eel, Anguilla japonica, along the western Mariana Ridge is considered one of the longest animal migrations. To establish an appropriate conservation policy for this species, a complete life cycle study is required, but the migratory routes of anguillid eels remain poorly documented. Anguilla japonica, A. marmorata, and A. bicolor pacifica are three common eel species in Taiwan. The present study used pop-up archival transmitting tags to track their movements during the oceanic phase of their migration. Twenty silver eels (farmed and wild) were tagged and released near the Gueishan and Liuchiu Islands. All three species in the Gueishan Island group were entrained in the Kuroshio Current, and pop-up tag data showed that, after 23 days, the farthest distance travelled was approximately 1,500 km, to the southern waters of Yakushima, Japan. In comparison, eels released near Liuchiu Island moved in the opposite direction, which suggests that they were influenced by the recirculation in the southwestern waters of Taiwan. The migration speed of eels was estimated to be between 12.9 km/d and 65.2 km/d. Several eels exhibited diel vertical migration behavior, moving into deeper water during the daytime and ascending into shallower waters at night. The farmed eels exhibited similar patterns of diel vertical migration to wild eels. The results of this study suggest that eels from Taiwan travel through the Kuroshio Current during their early migration, irrespective of species and source. Of importance, farmed eels appeared to behave similar to wild ones following artificial release. This information provides important rationale for releasing cultivated eels for resource enrichment programs.

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On Argentodromas bellanella gen. nov., sp. nov. (Crustacea, Ostracoda) from a Stream in Northeastern Argentina (South America)

Argentodromas bellanella gen. nov., sp. nov. is here described from streams in the province of Misiones, in northeastern Argentina. The new genus and species belong to the family Notodromadidae. Most species in the family have morphological adaptations to a hyponeustic mode of life: their carapaces have lip-like protrusions of the valve margins near the mouth and a flat plate-like expansion of the ventral part. The new genus can be distinguished from other genera in the subfamily Notodromadinae based on valve ornamentation (surface of valves covered with polygonal elevations and many pores with setae), the ventral plate-like expansion which is set with 3-4 rows of rounded elevations and bordered with an elevated outer list, eye tubercles softly pronounced, and soft parts features (male prehensile palps moderately asymmetrical and both with elongated first segments, posterior seta of caudal ramus longer than terminal claws and anterior seta present, hemipenis with rounded outer lobe and small rounded inner lobe). For comparative purposes, valves and carapaces of species in three other Notodromadinae genera (Newnhamia, Kennethia, Notodromas) are also illustrated and re-diagnosed.

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Accumulations of Fossils of the Whale Barnacle Coronula bifida Bronn, 1831 (Thoracica: Coronulidae) Provides Evidence of a Late Pliocene Cetacean Migration Route through the Straits of Taiwan

This paper describes a remarkably prolific accumulation of the whale barnacle Coronula bifida Bronn, 1831 in sediments of late Pliocene to earliest Pleistocene age from central Taiwan. Extant Coronula is host-specific to baleen whales; as such, this accumulation of Coronula fossils represents a site where cetaceans congregated during the Plio-Pleistocene - perhaps for breeding. Although whale bones are found at the site, they are rare and fragmentary; the relatively robust shells of Coronula are thus a useful proxy for establishing ancient cetacean migration routes.