Unicapsulocaudum mugilum, Yang & Zhou & Zhao & Huang & Huang, 2017

Yang, Chengzhong, Zhou, Yang, Zhao, Yuanjun, Huang, Wei & Huang, Cheng, 2017, Erection of Unicapsulocaudum mugilum gen. et sp. nov. (Myxozoa: Ceratomyxidae) based on its morphological and molecular data, Journal of Natural History 51 (9 - 10), pp. 457-467 : 461-462

Unicapsulocaudum mugilum sp. nov.

Vegetative stages: The species is coelozoic in the gallbladder and many developing spores mixed with fish tissues, forming a lump floating in the bile (see Figure 1a, b ). There were about 270 junior developmental-stage spores in a lump, and each spore had no definite tapering tail and horn-like protuberance which are described in the mature spore (see Figure 1a ). At this stage, the spores were oval with a single polar capsule inside, and the spore sizes were very different. Compared to the junior stage, in the senior developmental stage the elongated tails could be observed (see Figure 1b ).

Mature spores: With characters of the genus. Spores measured 2.9 ± 0.3 (2.0– 3.0) μm in length and 25.4 ± 3.8 (18–29) μm in thickness (n = 15). The polar capsule was 5.2 ± 1.2 (3.0–7.0) μm in length and 2.6 ± 0.3 (2.0–3.0) μm in thickness (n = 15). There was a polar filament with two coils inside the polar capsules (see Figures 1 and 2 ). The angle formed by the vertical axis of coils and the vertical axis of the spore was about 45° ( Figure 2 ).

Type and only known host: Mugil cephalus L., 1758.

Type locality: Coastal waters of Xiamen , East China Sea, China .

Site of infection: Gall bladder.

Prevalence: The prevalence of the infection was 3/11 (27.3%).

Deposition of type materials: A syntype (mounted in glycerin-alcohol-formalin) has been deposited in the collection centre of the Key Laboratory of Animal Biology of Chongqing, Chongqing Normal University, Chongqing, China (Coll. No. xm-20070601) . The DNA sample has been deposited in the same location, with the code number xm_Um-20070601 .

Etymology: The word mugilum comes from the scientific name of the type-host fish genus.

Figures

Figure 1. Light micrographs of the myxospore of Unicapsulocaudum mugilum sp. nov. (a) and (b) are developing stages (a is junior stage); (c–h) are mature spores of Unicapsulocaudum mugilum sp. nov. Scale bar = 10 μm.

Figure 2. Line drawing of the myxospore of Unicapsulocaudum mugilum sp. nov. in frontal view (a–c) and lateral view (d). Scale bar = 10 μm.