Halophila ovalis (R.Brown) J.D.Hooker, 1858

Halophila ovalis, also known as the paddle weed, spoon grass, or dugong grass, belongs to the family Hydrocharitaceae. This seagrass is a small herbaceous plant that can be found growing naturally in sea beds and various saltwater habitats across the Indo-Pacific region.

Current Status of Name :
This name is currently accepted taxonomically.

Rank: Species

Environment: Marine

Reproductive Structures:

• Flowers are small, solitary, and bisexual (male and female parts in the same flower)
• Flowers are borne on a slender peduncle (flower stalk) emerging from the leaf sheath
• Flowers have 3 greenish-white petals and 3 sepals
• Male parts consist of 3 anthers, female parts consist of 3-6 carpels

Fruits and Seeds:

• Fruits are small, globose to ovoid, and slightly beaked
• Each fruit contains a single seed
• Seeds are oval, with a thin seed coat and no endosperm

Importance:

Halophila ovalis, though small, plays a significant role in the marine environment:

Food Source:

Despite its diminutive size, Halophila ovalis is a vital food source for various marine herbivores. Dugongs, for instance, relish these miniature seagrass meadows, hence the nickname “dugong grass.”
Habitat Provider:

The dense meadows formed by Halophila ovalis transform into havens for a variety of marine creatures. Fish, invertebrates, and even juvenile stages of other species find shelter and nursery grounds within these underwater havens.
Sediment Stabilization:

The root network of Halophila ovalis acts like a silent guardian, trapping and stabilizing sediments on the seabed. This plays a crucial role in preventing erosion and maintaining the integrity of the marine environment.

Habitat and Ecology:

• Found in shallow coastal waters, typically at depths of 0.5-15 m
• Prefers sandy or muddy substrates in sheltered bays, lagoons, and estuaries
• Tolerates a wide range of salinities from brackish to marine
• Often forms dense meadows or grows intermixed with other seagrass species
• Provides food and habitat for various marine organisms, including small invertebrates and fish
• Helps stabilize sediments, improve water quality, and contribute to nutrient cycling
• Reproduces both sexually (via seeds) and asexually (via rhizome fragmentation and growth)

Distribution:

• Widely distributed in tropical and subtropical regions of the Indian and Pacific Oceans
• Also found in the Mediterranean Sea, Red Sea, and parts of the western Atlantic Ocean

Conservation Status:

• Listed as Least Concern (LC) on the IUCN Red List of Threatened Species
• Faces threats from coastal development, pollution, and climate change impacts

Halophila ovalis is a widely distributed and ecologically important seagrass species. Its small size, oval-shaped leaves, and ability to thrive in a range of coastal habitats make it a valuable component of many seagrass ecosystems. Despite its global distribution, it faces threats from human activities and environmental changes, highlighting the need for conservation efforts to protect this species and its associated ecosystems.