Orientomysis meridionalis ( Liu and Wang, 1983 ) Fukuoka & Murano, 2005

Fukuoka, Kouki & Murano, Masaaki, 2005, A revision of East Asian Acanthomysis (Crustacea: Mysida: Mysidae) and redefinition of Orientomysis, with description of a new species, Journal of Natural History 39 (9), pp. 657-708 : 678-679

Orientomysis meridionalis ( Liu and Wang, 1983) comb. nov.

( Figure 5 ) Acanthomysis meridionalis Liu and Wang 1983: 525 , Figure 2 ; 1986: 195; Müller 1993: 195 (list); Liu and Wang 2000: 251–253, Figure 94.

Type locality

Shatian, Wuchuan, Guangdong, southern China .

Material examined

One male (5.2 mm) and one immature female (4.6 mm), Wuchuan , Guangdong, southern China, coastal water, 2 May 1978, on loan from Liu and Wang .

Remarks

The specimens examined in this study are a part of those collected together with the type specimens of O. meridionalis . These specimens are slightly different from the original description by Liu and Wang (1983) in the maxilla, the endopod of the fourth male pleopod and the telson. The maxilla illustrated by Liu and Wang (1983) is not armed with tiny spines on the outer margin of the second endopod segment, whereas in the present specimens the outer margin is armed with five tiny spines in the male and two in the female among long setae ( Figure 5B ). The exopod of the fourth male pleopod is not armed with setae on the distal end of the proximal segment in the original illustration, while in the present specimen the proximal segment bears a long plumose seta at the inner distal angle and a tiny seta at the outer distal angle ( Figure 5C, D ). The dorsal surface of the telson is smooth in the original illustration, whereas it is armed with a pair of short spines in the present specimens ( Figure 5E ).

Orientomysis meridionalis is allied to O. okayamaensis and O. serrata in the following characters: last one or two abdominal somites are furnished with a row of spines; the larger lateral spines of the telson increase in size posteriorly; and the apex of the telson is armed with two pairs of strong spines. Differences among these species are summarized in Table VI.

Distribution

This species has only been recorded from the South China Sea off Guangdong, southern China ( Liu and Wang 1983, 1986).

Figures

Figure 2. Orientomysis hwanhaiensis (Ii, 1964) comb. nov. (A, B) Telson, dorsal; (C–F) distal end of telson, dorsal. (A) Male (12.2 mm), syntype; (B) female (13.6 mm), syntype; (C) male (9.8 mm), East China Sea, NSMT-Cr 15559; (D) male (7.5 mm), East China Sea, NSMT-Cr 15559; (E) female (10.7 mm), East China Sea, NSMT- Cr 15559; (F) female (10.6 mm), East China Sea, NSMT-Cr 15559.

Figure 5. Orientomysis meridionalis (Liu and Wang 1983) comb. nov. Male (5.2 mm). (A) Anterior part of body, dorsal; (B) maxilla, posterior; (C) fourth pleopod, posterior; (D) distal part of fourth pleopod, anterior; (E) uropod and telson, dorsal.