Nigrobaetis facetus
General appearance
Body size medium up to 5mm long (excluding antennae & cerci)
Body cylinderical & elongated, dark brown to black with large white markings at posterior end of abdomen
Head
The details for mouthparts
illustrated in the following pictures
Thorax
A pale three-forked mark
on mesonotum
Hingwing pad absent
Abdomen
Pale on tergum IV giving an inverted triangular dark mark & a large pale area from posterior half of tergum VIII to anterior half of tergum X
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Legs |
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Its mouthparts of labrum, mandibles, maxillae and labium are illustrated as follow (hypopharynx is excluded).
Labrum |
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Maxillae |
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Mandibles |
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Labium |
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Distribution:
In Hong Kong, specimens are recorded from Pak Ngau Shek, Tong Min Tsuen (Lam Tsuen River), Pui O (Lantau Island),
Kap Lung, Tan Shan River, Ho Chung (Sai Kung)and Tai Shui Hang (Ma On Shan).
Remarks:
Larvae of Nigrobaetis facetus can be distinguished from other baetids by its distinctive abdominal pattern.