Species Card of Copepod
Calanoida ( Order )
    Diaptomoidea ( Superfamily )
        Acartiidae ( Family )
            Acartia ( Genus )
                Acartiura ( Sub-Genus )
Acartia (Acartiura) omorii  Bradford, 1976   (F,M)
Syn.: Acartia clausi : Mori, 1937 (1964) (p.103, figs.F,M); Shen & Bai, 1956 (p.223, figs.F,M); Tanaka, 1965 (p.387, figs.F,M); Anraku, 1975 (p.79, microdistribution); Hirota & Hara, 1975 (p.115, fig.5); Hirota & Hara, 1975 (p.115, fig.5); Hirota & Uno, 1977 (p.77, eggs, seasonal abundance); Uye, 1980 (p.1, development); 1980 a (p.11, development); ? Hirota 1981 (p.19, Table 1, length-weight-CHN, in Inland Sea, Japan); Uye, 1981 (p.255, egg production); 1982 (p.149, relation length-weight-C-N); 1982 a (p.55, population dynamics, production); Uye & al., 1984 (p.390, resting eggs-survival); Uye, 1985 (p.440, resting eggs); ? Ayukai, 1987 (p.137, feeding, defaecation rate).
Ref.:
Bradford, 1976 (p.173,figs.F,M); Ueda, 1986 b (p.134, figs.F,M); Kang Lee, 1990 (p.378, figs.F,M, Rem.); Yoo & al., 1991 (p.259); Chihara & Murano, 1997 (p.670, Pl.16: F,M); Bradford-Grieve, 1999 (N°181, p.5, figs.F,M); Barthélémy, 1999 (p.858, 862, figs.F); 1999 a (p.9, Fig.22, E, F); Soh & Suh, 2000 (p.332, Table I); Seuront, 2005 (p.1301, tab.I, Rem.).
Species Acartia (Acartiura) omorii - Plate 1 of morphological figuresissued from : J.M. Bradford in N.Z. J. Mar. Freshw. Res., 1976, 10 (1). [p.174-175, Figs.11,12].
Female (from Japan): 1a, habitus (dorsal view); 1b, idem (lateral view); 1c-e, P5; 2a-c, genital segment (dorsal view); 2d-f, idem (lateral view).


Species Acartia (Acartiura) omorii - Plate 2 of morphological figuresissued from : J.M. Bradford in N.Z. J. Mar. Freshw. Res., 1976, 10 (1). [p.175, Fig.13].
Male (from japan): a, habitus (dorsal view); b, idem (lateral view); c, posterior surface of P5; d, terminal segment of left P5.


Species Acartia (Acartiura) omorii - Plate 3 of morphological figuresissued from : O. Tanaka in Publs Seto Mar. Biol. Lab., 1965, XII (5). [p.388, Fig.244]. As Acartia clausi.
Female: a, habitus (dorsal); b, last thoracic segment and urosome (left lateral side); c, proximal portion of A1; d, P5.
Nota: Rostral filament absent.
Abdomen 3-segmented, contained 3.3 times in the length of cephalothorax
The abdomen segments and furca are in the proportional lengths as 41:24:14:21 = 100.
Thorax segments and genital segment covered with fine hairs.
P5: in the middle segment squarish in shape; the claw-like spine swollen at the basal portion and spinulose on each side; the outer marginal seta longer than the claw.
Genital and 2nd abdominal segments fringed with fine teeth on the distal margin

Male: P5. Nota: Lateral corner of last thoracic segment furnished with short hairs.
Abdomen contained 3.1 times in the length of cephalothorax.
The abdominal segments and furca are in the proportional lengths as 15:30:19:7:11:18 = 100.
2nd to 4th fringed with minute spinules on the dorsal distal margin.


Species Acartia (Acartiura) omorii - Plate 4 of morphological figuresissued from : C.-j. Shen & S.-o. Bai in Acta Zool. sin., 1956, 8 (2). [Pl.VII, Figs.49-51]. As Acartia clausi.
Male (from Chefoo): 49, habitus (dorsal); 50, P5.

Female: P5.

Nota: In the specimens, the 1st and 2nd abdominal segments of the female and the 2-4 abdominal segments of the male are without spinules on their posterior margins.


Species Acartia (Acartiura) omorii - Plate 5 of morphological figuresissued from : H. Ueda in J. Oceanogr. Soc. Japan, 1986, 42. [p.136, Fig.2]. Comparative aspects between A. omorii, A. hudsonica and A. clausi.
A. omorii (from Maizuru Bay, Japan): Female: A-B, urosome (dorsal and lateral, respectively);. Male: C, P5 (posterior view); D-E, 3rd segment of right P5 (other specimens).

A. hudsonica (from Maizuru): Female: F-G, urosome (dorsal and lateral); H, P5 (posterior view); I-J, 3rd segment of right P5 (other specimens).

A. clausi (after Bradford, 1976): Female: K-L, genital segment (dorsal and lateral, respectively).


Species Acartia (Acartiura) omorii - Plate 6 of morphological figuresissued from : H. Ueda in J. Oceanogr. Soc. Japan, 1986, 42. [p.136, Table 1].
Comparative list of distinctive characters of A. omorii and A. hudsonica, after Bradford, 1976.


Species Acartia (Acartiura) omorii - Plate 7 of morphological figuresissued from : T. Mori in The pelagic Copepoda from the neighbouring waters of Japan, 1937 (2nd edit., 1964). [Pl.50, Figs.8-13]. As Acartia clausi.
Female: 8, habitus (dorsal); 10, P5; 13, forehead (ventral).
Nota: Rostral filaments absent. Urosomal segments with fine spinules on the posterior margins. A1 with without spines on the proximal segments, and extend about the end of the genital segment. The middle segment of P5 is nearly as long as its width; the claw-like terminal segment is stout; the marginal seta is much longer than the terminal segment.

Male: 9, habitus (dorsal); 11, P5; 12, right A1 (distal portion).
Nota: Right leg of P5 consists of 4 segments; the inner margin of the 2nd segment has a blunt process of the distal portion; the 3rd segment also has a blunt process on the inner margin. Left leg of P5 consists of 3 segments; the terminal segment has a vermiform appendage and 1 spine.


Species Acartia (Acartiura) omorii - Plate 8 of morphological figuresissued from : Y.-S. Kang & S.-S. Lee in Bull. Korean Fish. Soc., 1990, 23 (5). [p.380, Fig.1].
Female (from Korea): D, habitus (dorsal); E, 1st and 2nd urosomal segments (dorsal); F, genital segment (lateral).

Male: A, habitus (dorsal); B, P5; C, inner lobe of 3rd segment of right P5.


Species Acartia (Acartiura) omorii - Plate 9 of morphological figuresissued from : R.-M. Bathélémy in J. Mar. Biol. Ass. U.K., 1999, 79. [p.860, Fig.3, E, F].
Scanning electon miccrograph. Female (from Maizuru Bay, Japan): E, genital double-somite (ventral); F, genital area (external ventral view); Note the two lengthened genital slits (small arrows) each protected by a lamellar flap (arrowheads) and the medioventral position of genital area.
Scale bars: 0.030 mm (E, F).
Symbol: * = fixation of the spermatophore.


Species Acartia (Acartiura) omorii - Plate 10 of morphological figuresissued from : L. Seuront in J. Plankton Res., 2005, 27 (12). [p.1303, Table I].
Comparisons of distinctive characters of Acartia species closely related to each other.


Species Acartia (Acartiura) omorii - Plate 11 of morphological figuresissued from : L. Seuront in J. Plankton Res., 2005, 27 (12). [p.1304, Table II].
Prosome length and body proportions of Acartia omorii males and females sampled in the southern bight of the North Sea (France) and the type locality (Tokyo Bay, Japan) and Acartia clausi males and females sampled in the southern bigght of the North Sea (France).


Species Acartia (Acartiura) omorii - Plate 12 of morphological figuresissued from : L. Seuront in J. Plankton Res., 2005, 27 (12). [p.1304, Table III].
Allometric relationships obtained between prosome length and different morphometric ratios for Acartia omorii adult males and females sampled in the southern bight of the North Sea (France) and in the type locality (Tokyo Bay, Japan).


Species Acartia (Acartiura) omorii - Plate 13 of morphological figuresIssued from : R. Hirota & S. Uno in Bull. Plankton Soc. Japan, 1977, 24 (2). [p.80, Fig.3, C, D].
Pelagic eggs of Acartia clausi (= A. omorii) from vicinity of Amakusa-Matsushima (western Kyushu, Japan).


Species Acartia (Acartiura) omorii - Plate 14 of morphological figuresIssued from : M. Chihara & M. Murano in An Illustrated Guide to Marine Plankton in Japan, 1997. [p.674, Pl. 16, fig.6 a-g].
Female: a, habitus (dorsal); b, last thoracic segment and urosome (dorsal); c, same (lateral, right side); d, P5.

Male: e, habitus (dorsal); f, last thoracic segment and urosome (dorsal); g, P5
Nota: numbers show caracteristics of this species to compare with A. hudsonica.


Species Acartia (Acartiura) omorii - Plate 15 of morphological figuresIssued from : H.Y. Soh & H.-L. Suh in J. Plankton Res., 2000, 22 (2). [p.332, Table I].
Distinctive characters of Acartia omorii.
a: referred from Ueda (1986).
Nota: Compare the distinctive characters with the closely related species A. hongi, A. hudsonica in the coastal waters of Korea, and A. bifilosa.

Compl. Ref.:
Ueda, 1987 (p.691); Hirakawa & al., 1990 (tab.3); Hirakawa, 1991 (p.376: fig.2); Uye & Takamatsu, 1990 (p.97, red-tide flagellate effects); Yoo, 1991 (tab.1); Hattori, 1991 (tab.1, Appendix); Hwang & Choi, 1993 (tab.3); Kimmerer, 1993 (p.267, tab.2); Uye & Kaname, 1994 (p.43, length v.s. fecal pellet volume); Kotani & al., 1996 (tab.2); Liang & Uye, 1996 (p.109, production); Mauchline, 1998 (p.507); Ueda & al., 2000 (tab.1); Shimode & Shirayama, 2004 (tab.2); Hsiao & al., 2004 (p.325, tab.1); Dur & al., 2007 (p.197, Table IV); Kang J.-H. & al., 2007 (p.82, fig.3, temporal variation vs. temperature & predation effect); Youn & Choi, 2007 (p.222: Table 1, egg production); Kang H.-K & al., 2007 (p.236, dynamic population, egg production, production); Ohtsuka & al., 2008 (p.115, Table 4, 5); Suzuki & al., 2008 (p.541, predation); Brylinski, 2009 (p.253: Tab.1, p.256: Rem.); Itoh & al., 2011 (p.129, vertical distribution); Hsiao S.H. & al., 2011 (p.475, Appendix I); DiBacco & al., 2012 (p.483, Table S1, ballast water transport); Tachibana & al., 2013 (p.545, Table 1, seasonal change 2006-2008); Suzuki, K.W. & al., 2013 (p.15, Table 2, 3, 4, estuaries, annual occurrence);
NZ: 5

Distribution map of Acartia (Acartiura) omorii by geographical zones
Species Acartia (Acartiura) omorii - Distribution map 2
Chart of 1996
Species Acartia (Acartiura) omorii - Distribution map 3issued from : H. Ueda in J. Oceanogr. Soc. Japan, 1986, 42. [p.136, Fig.1].
Distribution of A. omorii and A. hudsonica in Japanese inlet and cosatal waters.
Species Acartia (Acartiura) omorii - Distribution map 4issued from : S.-I. Uye in J. Exp. Mar. Biol. Ecol., 1982, 57. [p.65, Fig.10].
Generation of Acartia clausi ( = A. omorii) estomated from adult female cephalothorax length and relative abundance of CI and CIV as a percentage of all copepodites during the period from December, 1977 to September, 1978 in Onagawa Bay (Japan).
G: numero of the generation.

Nota: The life cycle is continuous throughout the year, while the fluctuation in population abundance is remarkable. The number of generations during the year is six.
If food is in excess, the females lay eggs at a physiologically maximum rate which is controlled by temperature (See Uye, 1981). Unless strong upwelling occurs, most eggs after spawning sink to the bottom and are inhibited from hatching for some period until being washed free from the bottom by wave action or tidal current (see Landry, 1978). Once eggs can hatch into nauplii, the larvae follow a characteristic growth mode, i.e. isochronal development (see Miller & al., 1977).
Species Acartia (Acartiura) omorii - Distribution map 5issued from : S.-I. Uye in J. Exp. Mar. Biol. Ecol., 1982, 57. [p.60, Fig.3].
Seasonal change in water temperature at depths of 1, 5, 10 m and near the bottom, and salinity at depths of 1 and 10 m at inermost part of Onagawa Bay (38°25'N, 141°30'E)
Species Acartia (Acartiura) omorii - Distribution map 6issued from : S.-I. Uye in J. Exp. Mar. Biol. Ecol., 1982, 57. [p.66, Table I].
Estimated generation lengths from field data compared with lengths predicted from temperature during development.
a: Prediction is made assuming temperature is 20°C, since the development rate does not increase above 20°C.
Uye (1980) has previously investigated the postembryonic development at various temperatures with excess food in the laboratory and found that the time taken from egg-laying to adult stage is 17.9 times duration of the embryo which can be expressed by the beleradek equation.
Species Acartia (Acartiura) omorii - Distribution map 7issued from : S.-I. Uye in Bull. Plankton Soc. Japan, 1980, 27 (1). [p.13, Fig.2].
Post-embryonic development of Acartia clausi (= A. omorii at 7.3, 11.2, 14.5, 16.4 and 20.3°C, cultured with excess food.
Each point is the time required for 50 % of individuals molting into each stage. Straight lines are fitted by the least squares to all points except one entering into N III.
Loc:
China Seas (Yellow Sea, East China Sea, South China Sea, Korea, Ilkwang Bay, Japan (Tokyo Bay, Izu, Onagawa, Toyama Bay, off Sanriku, Maizuru Bay, Fukuyama Harbor, Inland Sea, Ariake Sea, Amakusa-Matsushima, Tanabe Bay, souyh estuaries, Hokkaido), Taiwan, Kuroshio Current, California (Tomales Bay), Chile, SW North Sea (Calais Harbour)
N: 46 ?
Lg.:
(91) F: 1,22-1,17; M: 1,07-1; (119) F: 1,22-1,06; M: 1,19-0,94; (174) F: 1,05-0,94; M: 0,9-0,81; (866) F: 0,9-1,3; M: 0,8-1,2; {F: 0,90-1,30; M: 0,80-1,20}
Rem.: epipelagic.
Transport to Chile and California (San Francisco) without doubt in ship's ballast (Hirakawa, 1988, p.357), like in the port of Dunkirk, France (Seuront, 2005). After Brylinski (2009, p.256) this species has not been seen since in the Dunkerk harbour, and it is not posible to confirm the long-term establishment.
Last update : 15/12/2014
    to add your remark
  

 Any use of this site for a publication will be mentioned with the following reference :

Razouls C., de Bovée F., Kouwenberg J. et Desreumaux N., 2005-2014. - Diversity and Geographic Distribution of Marine Planktonic Copepods. Available at http://copepodes.obs-banyuls.fr/en 
[Accessed December 22, 2014]

© copyright 2005-2014 CNRS, UPMC

Webmaster
CNRS   Observatoire Océanologique de Banyuls sur Mer - Laboratoire Arago
UPMC - Paris Universitas

 

Version française
English version

 

Search

On the WEB of CNRS

 


Marine Planktonic Copepods

Marine Planktonic Copepods

 

Imprimer Contact Accueil Plan du site Accès restreint Retour Une du Labo Imprimer Contact Plan du site Crédits Téléchargez les Plug-Ins