Cardiovascular system of the Majidae (Crustacea: Decapoda)

Area of Science:

• Marine Biology
• Crustacean Anatomy
• Cardiovascular Physiology

Background:

• The circulatory system of crustaceans, particularly decapods, exhibits diverse morphologies.
• Understanding the cardiovascular system's anatomy is crucial for comprehending physiological functions in marine invertebrates.

Purpose of the Study:

• To meticulously map and describe the cardiovascular system of majid crabs (Majidae).
• To compare the arterial system of majid crabs with other malacostracan and decapod crustaceans.
• To classify the circulatory system of majid crabs based on anatomical findings.

Main Methods:

• Corrosion casting techniques were employed to visualize and map the arterial network.
• Detailed anatomical observations of arterial pathways and their distributions were conducted.

Main Results:

• The general structure of the majid crab circulatory system is comparable to other malacostracans, with notable distinctions in arterial systems.
• The anterior aorta exhibits unique complexity, supplying hemolymph to the brain, antennae, and eyestalks.
• Hepatic arteries are significantly larger and more branched in majid crabs compared to other decapods, supplying the hepatopancreas and gonads.
• The sternal artery arrangement in majid crabs differs from other brachyuran crabs, suggesting a potential symplesiomorphy.
• Sex-specific differences were observed in the posterior aorta.

Conclusions:

• The cardiovascular system of majid crabs presents a unique configuration within malacostracan crustaceans.
• Based on anatomical evidence, the circulatory system of majid crabs can be classified as "incompletely closed."
• The findings contribute to the comparative anatomy of crustacean circulatory systems.