186 Hemiaulus 半管藻 Phylum: Heterokontophyta 门：不等鞭毛門 Class: Mediophyceae 纲：中型硅藻綱 Order: Hemiaulales 目：半管藻目 Family: Hemiaulaceae 科：半管藻科 Morphology Cells possess rectangular girdle view and elliptical valves. There are two elevations with varied length at the ends of the apical axis. The elevations are parallel to pervalvar axis, with blunt or pointed tips, or claws at the end. Sibling cells are connected by elevations with roughly rectangular apertures. There are 52 species and variety within the genus Hemiaulus according to AlgaeBase website. The species are distinguished mainly based on elevations morphology and frustule areolation. 4 species are observed in Hong Kong coastal waters including H. hauchii, H. indicus, H. membranacus, and H. sinensis. H. sinensis cells possess short and thick elevations while they are long and thin for H. hauchii, resulting in long apertures between adjacent cells. The elevation ends of H. membranacus are blunt while H. indicus possess claws at the end of elevation. 形態 細胞殼環面觀呈矩形，殼面呈橢圓形。頂軸兩端有或長或短的凸起。突起和貫殼軸 方向平行，末端呈不同的特質，或尖或鈍，或者具小爪。相鄰細胞通過突起相連， 細胞間的空隙通常為矩形。根據AlgaeBase 的記錄，本屬52個物種（含變型）。不 同物種主要依據殼面突起的特徵以及硅質壁超顯微結構。香港海域常見物種有中 華半管藻，霍氏半管藻，印度半管藻和膜狀半管藻，但豐度很低。其中中華半管藻 殼面頂軸兩端的突起較為粗短，而霍氏半管藻的突起細長，且細胞間隙相對于中華 半管藻更大。印度半管藻的突起末端具小爪，相鄰細胞以小爪相連形成細胞鏈。膜 質半管藻的殼面突起較鈍，且細胞間隙較小。
RkJQdWJsaXNoZXIy NDk5Njg=