Two new species of marine amphipods, Grandidierella geetanjalae and Grandidierella khambhatensis, have been found by a team of researchers from Chilika and the Gulf of Khambhat, recently.

About Amphipods
Amphipods are an order of small crustaceans found in virtually all aquatic and some humid terrestrial environments worldwide. They are a diverse group, with over 10,700 recognized species, and are commonly known as scuds, sideswimmers, beach fleas, or sand hoppers. 

Key Characteristics

• Body Structure: Amphipods typically have a laterally compressed body, giving them a "C" shaped or humped-back appearance. They lack a carapace (the hard upper shell found on crabs and lobsters).
• Appendages: The name "Amphipoda" means "different feet," which refers to their specialized legs. They have several types of legs for different functions, including claw-like gnathopods for feeding and grasping, and pleopods and uropods for swimming, jumping, or burrowing.
• Eyes: Most species have sessile compound eyes that are flat on the head and lack eyestalks, although many subterranean and deep-sea species are eyeless.
• Size: Most amphipods are small, typically a few millimeters to a couple of centimeters long. However, deep-sea species can be much larger, with some specimens reaching up to 34 centimeters (13 inches) in length. 

Habitat and Diet
Amphipods are found from the deepest ocean trenches to high-altitude lakes and even damp leaf litter on land. 

• Habitat Diversity: While most species are marine, a significant number inhabit freshwater and brackish environments. Terrestrial species require humid environments because they lack the waxy exoskeleton layer that prevents desiccation.
• Diet: They exhibit diverse feeding strategies and are often detritivores or scavengers, consuming dead and decaying plant and animal matter. Some are herbivores that graze on algae, while others are omnivores or predators of smaller invertebrates. 

Ecological Importance
Amphipods play a vital role in ecosystems as a key link in the food web. 

• Nutrient Cycling: As detritivores, they are crucial to the decomposition of organic material, which helps recycle nutrients back into the environment.
• Food Source: They are a primary food source for many organisms, including fish, waterfowl, and marine mammals like gray whales.
• Bioindicators: Their sensitivity to water quality and pollution makes them useful as bioindicators for assessing ecosystem health in scientific research. 

Types of Amphipods
The order Amphipoda is currently divided into six suborders, including: 

• Senticaudata: The largest suborder, which includes most freshwater and terrestrial species (e.g., landhoppers).
• Hyperiidea: Exclusively marine and planktonic amphipods, many of which live in association with gelatinous animals like jellyfish and salps.
• Cyamidae: Highly specialized parasitic amphipods known as whale lice, which attach themselves to marine mammals.
• Caprellidae: Also known as "skeleton shrimp," these have elongated bodies and cling to algae and other structures. 

About Grandidierella Geetanjali and Grandidierella Khambhatensis
Grandidierella geetanjalae and Grandidierella khambhatensis are two newly discovered species of small, shrimp-like marine amphipods. Both are detritivorous crustaceans, meaning they feed primarily on organic matter and contribute to natural ecosystem cleaning processes. 

Grandidierella geetanjalae

• Discovery Location: This species was collected from the Chilika lagoon (a brackish water lake) near Rambha in the Ganjam district of Odisha, on the east coast of India.
• Naming: It was named in honor of Geetanjali Dash, the vice-chancellor of Berhampur University.
• Distinguishing Feature: It differs from close congeners by having a comparatively smaller spine on the posterior margin of the carpus of gnathopod 1 (a type of leg modified for feeding/grasping).
• Size: Measures between 5.5 and 6 mm in length. 

Grandidierella khambhatensis
Discovery Location: This species was collected from the Gulf of Khambhat in Gujarat, on the west coast of India.

• Naming: It was named after its type locality, the Gulf of Khambhat.
• Distinguishing Feature: It differs from its close congener G. perlata by having a hook-shaped uropod 3 ramus (part of the tail structure).
• Size: Measures between 5.5 and 6 mm in length. 

General Information

• Both species were identified and described by a joint team of researchers from Berhampur University (Odisha) and Hemchandracharya North Gujarat University (Gujarat).
• Their discovery was published in the journal Zootaxa.
• The species in the Grandidierella genus generally inhabit marine, estuarine, and coastal waters and are known for their sexually dimorphic gnathopods (males have much larger first gnathopods than females). 

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