Unnamed Stream, Shiwandashan Mtns., Guangxi, China

Environment

Environment

Affected by human activity

Affected by human activity

Agriculture

Agriculture

Massive

Surrounding area

This stream is situated on the southern slope of the Shiwandashan Mountains in Guangxi. Influenced by the monsoon climate at the northern edge of the tropics, it features abundant rainfall and distinct dry-wet seasons.

The average annual temperature ranges between 20.0-21.8℃, with an average annual precipitation of 2.000–2.700 mm. The stream is surrounded by subtropical evergreen broad-leaved forests dominated by Bambusa textilis and other species. With a forest coverage rate exceeding 98%, the area has nurtured rich biodiversity.

The stream experiences a dry season from November to April of the following year and a wet season from March to October. During the dry season, the water level gradually drops, exposing riverside rocks. In the rock crevices, abundant fallen leaves, dead branches, and toppled tree trunks are piled up, while water currents sweep leaves to gather around the toppled branches, forming a unique natural landscape.

Underwater landscape

Beneath the water, the stream is paved with gravel of various sizes, forming a beautiful substrate structure. There are almost no aquatic plants underwater, except for some emergent plants growing along the water’s edge. Large stones in the water are covered with algae, while small gravels are blanketed by mud particles, bamboo leaves, and dead branches—most of which are deposited along the current direction.

The narrow waterway prevents most large fish from entering, making it an ideal habitat for small fish to thrive. During the breeding season, juveniles of Parazacco fasciatus can be seen mixed among them. Additionally, a small population of Tanichthys albiventris inhabits the upper reaches of the stream.

Fishes, crustaceans & molluscs:

• Aphyocypris sp. (Xenocyprididae)
• Araiocypris batodes (Xenocyprididae)
• Aphyocypris normalis (Xenocyprididae)
• Parazacco fasciatus (Xenocyprididae)
• Macropodus opercularis (Osphronemidae)
• Channa nox (Channidae)
• Rhinogobius duospilus (Oxudercidae)
• Liniparhomaloptera disparis (Gastromyzontidae)

Crustaceans:

• Macrobrachium nipponense (Palaemonidae)
• Neocaridina denticulata (Atyidae)
• Indochinamon lanae (Potamidae)
• Brotia herculea (Pachychilidae)

Wetland plants:

• Acorus gramineus (Acoraceae)
• Pteris multifida (Pteridaceae)
• Dicranopteris pedate (Gleicheniaceae)

Mosses：

• Hypnum plumaeforme (Hypnaceae)
• Fissidens exilis (Fissidentaceae)

Threats to ecology

Aphyocypris sp. and Araiocypris batodes are both stunning native fish species, patchily distributed across the mountains of Guangxi, China. Unfortunately, with the continuous expansion of human activities—such as agricultural pollution from pig farms upstream of this stream—part of their habitat has been destroyed, leading to the temporary disappearance of wild populations.

In recent years, as awareness of wildlife conservation has grown, more people have joined the ranks of conservation efforts. To help others understand the living environment and underwater landscape of these small fish, I created this Aphyocypris sp. biotope aquarium. The Aphyocypris sp. in my tank are artificially bred to protect these beautiful little fish.

Riparian zone

Trees near the aquatic habitat

Many -

Bibliography

• Freshwater Fishes of China, P357, P375 by Li Fan
  ISBN 9787556712861
  
• Classification Atlas of Guangxi Freshwater Fishes, P92, P101, P274 by Xiao Shan, Lan Jiahu
  ISBN 9787572511349
  
• Colored Atlas of Chinese Melania, P61 by Du Lina, Yang Junxing
  ISBN 9787572510458
  
• The Raffles Bulletin of Zoology, 2008, Issue 1 - Araiocypris batodes, a new genus and species of cyprinid fish from northern Vietnam (Ostariophysi: Cyprinidae) by Conway, K.W., Kottelat, M
  
• The Raffles Bulletin of Zoology, 2023, Vol. 71, pp.70-86 - A new genus and three new species of freshwater crab (Crustacea: Brachyura: Potamidae) from central and northern Vietnam by Ng, P.K.L., Ngo, V.T.
  

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