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1.
Seiji Matsumoto Takeshi Kon Motoomi Yamaguchi Hirohiko Takeshima Yuji Yamazaki Takahiko Mukai Kaoru Kuriiwa Masanori Kohda Mutsumi Nishida 《Ichthyological Research》2010,57(1):71-77
The swamp eel Monopterus albus is widely distributed in tropical and subtropical freshwaters ranging from Southeast Asia to East Asia, and is unique in
its ability to breathe air through the buccal mucosa. To examine the genetic structure of this widespread species, molecular
phylogenetic analyses of mitochondrial 16S rRNA sequence (514 bp) were conducted for 84 specimens from 13 localities in Southeast
and East Asia. The analyses showed clearly that this species can be genetically delineated into three clades based on geographical
populations [China–Japan (Honshu + Kyushu), Ryukyu Islands, and Southeast Asia clades], with each clade exhibiting its own
reproductive behavior. Therefore, “M. albus” is believed to be composed of at least three species. The Southeast Asia clade with the highest genetic diversity may include
more species. The Ryukyu clade was estimated to have diverged more than 5.7 million years ago, suggesting that the Ryukyuan
“M. albus” is native. In contrast, in the China–Japan clade, all haplotypes from Japan were closely related to those from China, suggesting
artificial introduction(s). 相似文献
2.
The morphology of the early stage of Eumegistus was described from three specimens [E. brevorti: 23.0 mm in standard length (SL) juvenile; E. illustris: 5.8 mm SL postflexion larva, and 40.0 mm SL juvenile] recently rediscovered in museum collections. Larval and juvenile pigmentation
patterns were reported for the first time for this genus. The 5.8 mm SL postflexion larva of E. illustris had pigmentation on the head and anterior half of the body, through to the middle of the dorsal fin base. In larvae and juveniles
of both species, the outer side of the pelvic fin was pigmented. The two juveniles possessed several spines on the lachrymal
and protruding rays in the middle of the caudal fin. Although it is known previously that the notochord flexion occurs at
5.0–6.0 mm SL in E. brevorti, the reexamined 5.0 mm SL specimen had the notochord completely flexed. Furthermore, we could not confirm whether the previously
studied 4.0 mm SL specimen was E. brevorti because it was badly damaged. 相似文献
3.
Martin V. Sørensen Iben Heiner Ole Ziemer Birger Neuhaus 《Helgoland Marine Research》2007,61(4):247-265
One new kinorhynch genus and species and one new species from the genus Zelinkaderes are described from sandy sediment off Fort Pierce, Florida. The new genus and species, Tubulideres seminoli gen. et sp. nov. is characterized by the presence of the first trunk segment consisting of a closed ring, the second segment
of a bent tergal plate with a midventral articulation and the following nine segments consisting of a tergal and two sternal
plates. Cuspidate spines are not present, but flexible tubules are located on several segments, and in particular concentrated
on the ventral side of the second segment. Middorsal spines are present on all trunk segments and are alternatingly offset
to a position slightly lateral to the middorsal line. Zelinkaderes brightae nov. sp. is characterized by its spine formula in having middorsal spines on trunk segments 4, 6 and 8–11, lateroventral
acicular spines on segment 2, lateral accessory cuspidate spines on segments 2 and 8, ventrolateral cuspidate spines on segments
4–6 and 9, lateroventral acicular spines present on segments 8 and 9, and midterminal, lateral terminal and lateral terminal
accessory spines on segment 11. The spine formula of Z. brightae nov. sp. places it in a position in between Z. submersus and a clade consisting of Z. klepali and Z. floridensis. The new findings on Z. brightae nov. sp. have led us to propose an emended diagnosis for the genus. 相似文献
4.
A taxonomic review of three color morphotypes of the Sebastes inermis species complex established the existence of three valid species, viz. S. inermis, S. ventricosus, and S. cheni. The complex is defined by having two sharp lachrymal spines, the head weakly armed with nasal, preocular, supraocular and
parietal spines, and the caudal fin not distinctly emarginated. Sebastes inermis, known from southern Hokkaido southward to Kyushu, Japan, and the southern part of the Korean Peninsula, is characterized
as follows: body dark red or light brown dorsally and laterally when fresh, pectoral fin extending beyond level of anus when
depressed, pectoral-fin rays 15, anal-fin rays 7, pored lateral line scales 36–44 and gill rakers 31–37. Sebastes ventricosus, known from Iwate and Ishikawa Prefecture southward to Kyushu, Japan, and the southern part of the Korean Peninsula, is characterized
as follows: body somewhat greenish-black dorsally and dark silver ventrally when fresh, pectoral-fin rays 16, anal-fin rays
7–8, pored lateral line scales 43–49, and gill rakers 35–39. Sebastes cheni, known from Iwate and Akita Pref. southward to Kyushu, Japan, and the southern part of the Korean Peninsula, is characterized
as follows: body dark golden-brown dorsally and laterally when fresh, pelvic fin extending beyond anus when depressed, pectoral-fin
rays 17, anal-fin rays 8, pored lateral line scales 37–46 and gill rakers 32–37. In the genetic analysis, the presence or
absence of two AFLP fragments was completely fixed among the three species. Sebastes tokionis and S. guentheri are regarded as junior synonyms of S. inermis and S. ventricosus, respectively. A lectotype is designated for S. cheni, and a key to the three species of the S. inermis species complex provided. 相似文献
5.
A new species of sculpin,Icelus ecornis (Scorpaeniformes: Cottidae) from the southwestern Okhotsk Sea 总被引:1,自引:1,他引:0
A new cottid species,Icelus ecornis, is described on the basis of 31 specimens collected from 159–226 m in the southwestern Okhotsk Sea off Hokkaido, Japan.
It is distinguished from all other members of the genusIcelus by the following combination of characters: no supraocular and parietal spines; short blunt nuchal spine; cirri absent from
head and body, except for supraocular, parietal and nuchal regions; platelike scales of dorsal row bearing 6–10 long uniform
spinules; tubular lateral line scales bearing small spines on dorsal and posterior margins; large oval black spot on first
dorsal fin; 16–20 anal fin rays. 相似文献
6.
Recruitment courses of three amphidromous sleeper species, Eleotris acanthopoma, E. melanosoma, and E. fusca, were investigated at the surf zone adjacent to the river mouth and at five stations in the Teima River on Okinawa Island,
Japan. All three species occurred at the surf zone as pelagic larvae with transparent and compressed body, a conspicuous air
bladder, and an emarginated caudal fin. Eleotris fusca (16.0–19.6 mm in standard length: SL) sometimes possessed a vestige of the larval chin barbel and were larger than E. acanthopoma (9.7–13.2 mm SL) and E. melanosoma (11.2–12.8 mm SL). The pelagic larvae were also collected during full tide from the lower reaches of the tidally influenced
area of the river. The pelagic larvae may be carried in and out of the estuary with some tidal fluxes, and they may settle
when they reach the upper tidally influenced area where the salinity becomes extremely low. Body width and pigmentation of
newly settled larvae increased. E. fusca was considered to migrate upstream to the freshwater area against the flow of the river just after reaching the settled stage.
After settlement, all three species became completely pigmented, the caudal fin became round in shape, and the fin ray counts
became complete with growth. Also, E. acanthopoma dispersed widely to the lower part of the tidally influenced area or to the lower reaches of the freshwater area, E. melanosoma dispersed to the lower part of the tidally influenced area, and E. fusca dispersed upstream. 相似文献
7.
Symphurus hondoensis Hubbs, 1915, originally described only from the holotype taken in 390–542 m in Suruga Bay Japan, has long been considered
a junior synonym ofS. strictus Gilbert, 1905, known from waters off Hawaii, Japan, the Philippine Islands, and South Africa. Based on new information from
the holotype and a specimen recently captured from deep waters (789–815 m) off Amami-Oshima Island, southern Japan,S. hondoensis is now established as a valid species.Symphurus hondoensis is unique among congeners in having the combination of a 1–2–3 pattern of interdigitation of proximal dorsal pterygiophores
and neural spines, 10 abdominal vertebrae, 14 caudalfin rays, 111–113 dorsal-fin rays, 95 anal-fin rays, 59 total vertebrae,
105–106 scales in longitudinal series, blind side nearly as darkly pigmented as the ocular surface, and a black peritoneum.
Recognition ofS. hondoensis increases the number of described species ofSymphurus in waters off Japan to three (S. orientalis Bleeker,S. strictus, andS. hondoensis), with at least one more underscribed species occurring in deepwater hydrothermal vent areas off southern Japan. 相似文献
8.
Nucleotide-binding site-leucine-rich repeats (NBS-LRR) gene families are one of the major plant resistance genes. Genomic
NBS evolution was studied in many plant species for diverse arrays of NBS gene families. In this study, we focused on one
family of NBS sequences in an attempt to understand how closely related NBS sequences evolved in the light of selection in
domesticated plant species. A phylogenetic analysis revealed five major clades (A–E) and five subclades (A1–A5) within clade
A of cloned NBS sequences. Positive selection was only detected in newly evolved NBS lineages in subclades of clade A. Positively
selected codon sites were found among NBS sequences of clade A. A sliding-window analysis revealed that regions with Ka/Ks ratios of >1 were in the inter-motifs when paired clades were compared, but regions with Ka/Ks ratios of >1 were found across NBS sequences when subclades of clade A were compared. Our results based on a family of closely
related NBS sequences showed that positive selection was first exerted on specific lineages across all NBS sequences after
selective constraints. Subsequently, sequences with mutations in commonly conserved motifs were scrutinized by purifying selection.
In the long term, conserved high frequency alleles in commonly conserved motifs and changes in inter-motifs were maintained
in the investigated family of NBS sequences. Moreover, codons identified to be under positive selection in the inter-motifs
were mainly located in regions involved in functions of ATP binding or hydrolysis. 相似文献
9.
Charles Masembe Vincent B. Muwanika Silvester Nyakaana Peter Arctander Hans R. Siegismund 《Conservation Genetics》2006,7(4):551-562
Phylogeographic and population genetic studies using sequence information are frequently used to infer species boundaries and history; and to assess hybridization and population level processes. In this study, partial mitochondrial DNA (mtDNA) control region (423 bp) and cytochrome b sequences (666 bp) of Oryx beisa sampled from five isolated localities in its entire current range in Africa were analyzed to investigate the extent of genetic variation and differentiation between populations. We observed high nucleotide diversity at the control region in the total sample (6.3%) but within populations, it varied considerably ranging from 1.6% to 8.1%. Population pairwise genetic differentiation was generally significantly high (ranging from F
ST = 0.15, P<0.01 to F
ST = 0.54, P<0.001). In the total sample, 29 and 12 haplotypes were observed in the control region and the cytochrome b data sets respectively. For both data sets, the haplotypes cluster into three distinct clades (sequence divergence ranged from 6.0%–12.9% to 0.8%–1.0% for the control region and cytochrome b sequences, respectively) that do not correspond to sampling locations. Two of these clades are found in the same localities (Samburu and Marsabit), which represent the O.beisa beisa subspecies, whereas the last clade represents the fringe-eared oryx (O. beisa callotis). We interpret these findings in terms of an ancient hybridization and introgression between two formerly isolated taxa of Oryx beisa. 相似文献
10.
A new acropomatid, Malakichthys barbatus, is described on the basis of 27 specimens (76.3–180.1 mm SL) collected from Suruga Bay to Tosa Bay, along the southern Pacific
coast of Japan. The new species is unique in having numerous pairs of spines on the chin (a pair of spines in other congeners).
Although the new species resembles M. elegans in having a slender body (the depth less than 35% SL), the former is further distinguishable from the latter in having a
slender first proximal radial of the anal fin with no hollow (broad with a cone-shaped hollow in M. elegans), 43–48 lateral line scales (48–51), modally 21 gill rakers on the lower arm (modally 23), and a dark blotch on the opercle
(no remarkable blotch).
Received: July 2, 2000 / Revised: September 27, 2000 / Accepted: January 30, 2001 相似文献
11.
Embryonic, larval, and juvenile development of two cyprinid species belonging to the Zacco temminckii species' group, Z. temminckii (Temminck and Schlegel) and Zacco sp. (type A), are described and compared with each other from laboratory-reared and wild specimens. The eggs of both species
were closely similar except in diameter [1.92–2.20 mm in Z. temminckii vs. 1.60–1.75 mm in Z. sp. (type A)], being demersal, almost spherical in shape, transparent and unpigmented, with a pale yellow yolk, and no oil
globule. Hatching occurred 40–53 h after fertilization in Z. temminckii and after 47–60 h in Z. sp. (type A). The newly hatched larvae of both species [4.9–5.3 mm in body length (BL) in Z. temminckii and 3.5–4.8 mm BL in Z. sp. (type A)] also resembled each other, having a large transparent pear-shaped yolk and lacking body pigmentation. Myomere
counts of Z. temminckii and Z. sp. (type A) larvae and juveniles were 24–27 + 14–17 = 41–42 and 23–27 + 14–17 = 40–41, respectively. The yolk was completely
absorbed at 8.3 mm BL in Z. temminckii and at 6.6 mm BL in Z. sp. (type A). Notochord flexion was initiated and completed at 7.8 mm BL and 8.2 mm BL in Z. temminckii and at 6.3 mm BL and 6.6 mm BL in Z. sp. (type A), respectively. Aggregate numbers of all fin rays were completed at 17 mm BL in Z. temminckii and 13 mm BL in Z. sp. (type A). Although the morphology of larvae and juveniles of both species was very similar, differences in body length
of each developmental stage, the duration and process of disappearance of the adipose finfold, the anal fin ray counts, and
pigmentation on the lateral body surface were clearly recognized.
Received: August 10, 2001 / Revised: March 14, 2002 / Accepted: March 27, 2002 相似文献
12.
Larvae of two paralichthyids, Pseudorhombus oculocirris and P. arsius, are described and illustrated from specimens collected off Tosa Bay, southern Japan. Peudorhombus oculocirris larvae (5 specimens, 4.5–7.8 mm BL) are characteristic in having 6 or 7 elongated anterior dorsal fin rays and poorly developed
head spines and melanophores on the tail. Pseudorhombus arsius larvae (3 specimens, 5.3–8.4 mm BL) are distinctive in having 11 or 12 elongated anterior dorsal fin rays and well-developed
head spines, including a row of spines on the sphenotic.
Received: June 28, 2001 / Revised: November 2, 2001 / Accepted: November 22, 2001 相似文献
13.
A new freshwater goby, Rhinogobius wangi, was collected from a small tributary of the Hanjiang Basin, Guangdong Province, southeastern China. The species can be distinguished
from all congeneric species by the following unique combination of features: second dorsal fin rays I, 8; anal fin rays I,
7; pectoral fin rays 16; rather large scales as longitudinal scale series 26–27; predorsal scales 8–9; vertebral count 10 + 17 = 27;
seven parallel, deep brown oblique stripes crossing on cheek in male; branchiostegal membrane with brownish-red spots in male;
seven longitudinal deep brown lines on lateral side of body; pectoral fin base with a blackish-brown bar. A key to all nominal
species with high vertebral counts from China (Hanjiang to Chiangtangjiang basins), Taiwan, and Japan is also provided. 相似文献
14.
15.
Atsushi Fukui Miyuki Suzuki Yachiyo Suzuki Itsuro Uotani 《Ichthyological Research》2002,49(2):159-164
The early ontogeny of Lophonectes gallus (Bothidae) is described based on 83 specimens (1.9–17.5 mm BL), collected from the Tasman Sea off southeastern Australia.
The larvae are diagnosed by the following array of characters: vertebrae 10 + 30–31 = 40–41; one elongated dorsal fin ray
and several melanophores present on gut in preflexion stage (1.9–4.7 mm BL); and spines on posterior basipterygial process,
and urohyal, cleithrum, and epiotic without spines after postflexion stage (8.0–17.5 mm BL). The larvae are relatively small
at metamorphosis (15–18 mm BL) compared with other bothid larvae.
Received: March 22, 2001 / Revised: December 12, 2001 / Accepted: December 26, 2001 相似文献
16.
Yukio Iwatsuki Seishi Kimura Hirokazu Kishimoto Tetsuo Yoshino 《Ichthyological Research》1996,43(4):417-429
Gerres macracanthus Bleeker, 1854, for many years having been explicitly or tentatively synonymized withG. filamentosus Cuvier, 1829, is redescribed as a valid species.Gerres macracanthus differs fromG. filamentosus in lacking vertical rows of dark ovoid spots on the body, having instead only indistinct vertical bands in both subadult
and adult stages, in addition to shorter second and third anal fin spines (9.1–13.9% and 10.4–14.4% of standard length [SL]
vs. 12.3–19.6% and 11.9–17.3% of SL), fewer ored lateral line scales (41–44 vs. 43–46) and fewer scales between the base of
the 5th dorsal fin spine and the lateral line (4–5 vs. 4 1/2–5 1/2), and above and below the lateral line (5 1/2–6 1/2/9 1/2–10
1/2 vs. 6 1/2–7 1/2/10 1/2–11 1/2). AlthoughG. filamentosus has similarly, indistinct vertical bands on the body up to ca. 100 mm SL, specimens over ca. 100 mm SL develop diffuse ovoid
spots in each vertical band. Furthermore,G. macracanthus is generally a smaller species, apparently attaining a maximum size of ca. 170 mm SL, compared with ca. 250 mm SL forG. filamentosus. Formerly known from the Philippines, Indonesia, New guinea, India and the Arabian Gulf,G. macracanthus is newly-recorded from Japan, China, the Gulf of Thailand, the Red Sea and South Africa. A lectotype and three paralectotypes
are designated forG. macracanthus Bleeker, 1854, in addition to a neotype forG. filamentosus Cuvier, 1829. 相似文献
17.
Noriyuki Fujii Kunihiko Ueda Yasuyuki Watano Tatemi Shimizu 《Journal of plant research》1999,112(1):87-95
Primula cuneifolia Ledeb. (Primulaceae), we analyzed intraspecific variation of the nucleotide sequences of non-coding regions of chloroplast
DNA: the intergenic spacers between trnT (UGU) and the trnL (UAA) 5′exon, the trnL (UAA) 3′exon and trnF (GAA), and atpB and rbcL. In 20 populations of P. cuneifolia, 22 nucleotide substitutions and five insertions/deletions were inferred, and their genetic distances ranged from 0.001 to
0.008. Eight distinct haplotypes could be recognized and each haplotype was found to be geographically structured. Three major
clades (the Northern, Hokkaido and Southern clades) were revealed in phylogenetic analyses of the haplotypes. The haplotypes
of the Northern clade had a wider distribution area in the populations of Mt. Rausu and Rishiri Island of eastern and northern
Hokkaido in Japan, northward to Unalaska Island in the Aleutians, and those of the Hokkaido clade were distributed in the
populations of central Hokkaido and Mt. Iwaki of the northern Honshu in Japan; in addition, those of the Southern clade were
observed only in the populations of the central Honshu. It was shown that the genetic diversifications of the Southern clade
were higher than those of the Northern and Hokkaido clades. Furthermore, it was shown that the topology within the Southern
clade was hierarchical, and the haplotypes of the Southern populations in the clade were derivative. From these results, we
concluded that the cpDNA haplotypes of the three clades in P. cuneifolia arose and assumed the present distribution areas through several cycles of glacial advance and retreat in the Pleistocene.
Received 24 June 1998/ Accepted in revised form 28 December 1998 相似文献
18.
Investigation of the life history of corals is hampered by an inability to identify early recruits. In this study, the pattern
of formation and morphology of the juvenile skeletons of three laboratory-reared pocilloporids, Seriatopora hystrix, Stylophora pistillata and Pocillopora damicornis, were compared to determine whether they could be reliably distinguished. The pattern of skeleton formation, including the
origin and structure of the septa, columella and corallite wall was similar in all species. Following the completion of the
primary corallite wall after 4–5 days, these species could be identified by differences in the diameter of the primary corallite.
The mean diameter (±SE) of each species differed markedly: S. hystrix 400 ± 2.7 μm, range 325–450 μm; S. pistillata 505 ± 3.5 μm, range 400–550 μm; P. damicornis 697 ± 7.5 μm, range 492–885 μm. Values for the primary corallite diameter overlapped in only 3% of samples, demonstrating
the potential utility of this feature as a tool for classifying recruits obtained from the field.
Accepted: 4 January 2000 相似文献
19.
S. Víllora-Moreno 《Polar Biology》1998,19(5):336-341
A new species of marine tardigrade is described coming from the muddy sediment of the Antarctic deep sea. Angursa antarctica sp. nov. is characterized by the presence of balloon-shaped primary clavae, long lateral cirri, long cephalic cirri, spines
on legs I, hemispherical capsule-shaped papillae on legs IV, and short external peduncles. Geographical distribution of the
genus Angursa extends to Antarctic waters, suggesting a cosmopolitan distribution for this bathyal and abyssal genus. A table comparing
the main differentiating characteristics of the species of Angursa is presented.
Received: 25 July 1997 / Accepted: 9 November 1997 相似文献
20.
Showe-Mei Lin 《Journal of applied phycology》2006,18(3-5):671-678
Four flattened Gracilaria species have been reported from Taiwan: G. spinulosa, G. vieillardii, G. textorii and G. punctata, identified based on branching pattern, the presence or absence of spines, and characters that often vary seasonally. Gracilaria spinulosa was originally described from the type locality, Tainan. Species with toothed margins are usually referred to G. “vieillardii”; those with smooth margins to G. “textorii”, and those with smooth margins and dark spots scattered over the blade to G. “punctata”. Molecular analyses show that specimens with marginal teeth cluster in three different groups: a G. “vieillardii” clade, a G. spinulosa clade, and a clade sister to G. spinulosa. An undescribed species comprises the third clade, which is distinguished by its relatively large gonimoblast cells and weakly developed tubular nutritive cells. The three clades can be separated by the character of the tubular nutritive cells, the size of gonimoblast cells and certain vegetative features. Plants with entire margins form a single clade characterized by cystocarps with basal tubular nutritive cells and their absence in the cystocarp cavity. They are nested in the Hydropuntia complex and are referred to as Gracilaria “punctata” here. The records of G. textorii and G. punctata from Taiwan require reinvestigation in comparison with the Japanese species. 相似文献