User:EloiseBrindle/Guinotellus melvillensis

The Guinotellus melvillensis is a rare and unusual species of crab that has only been recorded in the Western Central Pacific, more specifically the Philippines. This species comes from the Xanthidae family (which comprises the common mud crabs) (4), in the genus Guinotellus. The Guinotellus melvillensis is the only crab of this family within the genus.

They have been found in four locations all within the Philippines and at varying depths at each location, with some specimens being found in the intertidal as well as subtidal microhabitats.

Description
The Guinotellus melvillensis has an anterolateral margin that does not meet the orbital margin but continues to meet antero-external region of the buccal frame. It also has a distinct subhepatic cavities present, with the chelipeds and walking legs that can be neatly fastened together against the carpus, which are ovoid and smooth.

As there is limited research on this species the morphology can be described having the morphology being the most similar to species of hypocolpus. Which can be found in reef prairies of Thalassodendron

They are especially similar in the structure of the basal antennal article, the anterior portion of the sternum, the form of the male abdomen, the cristate anterolateral margin of the carapace, and the way the fingers, palm, and carpus of the chelae follow the curve of the body surface against which they are fastened together

Life History
The Guinotellus melvillensis are commonly found with the Benthic and tropical zones of the ocean. They are members of order Decapoda and are mostly gonochoric. Their mating behaviour involves precopulatory courtship rituals which are common through olfactory and tactile cues. The reproduction of the Guinotellus melvillensis usually involves indirect sperm transfer

The movement of these creature is based on the walking legs that they possess. These walking legs densely setose at margins, less so on dorsal and ventral surfaces. They are relatively short, with their first walking legs being the longest.

Although the Guinotellus melvillensis has only be found in the Philippines, its larval stages can be compared to that of the family Xanthidae that it is a part of. The crab goes through 5 stages, four zoeal stages and a megalopa stage to end their larval life to enter into the adult stage.

The diet of the Guinotellus melvillensis is somewhat unknow but from information taken from the family Xanthidae it can be suggested. Crustaceans are described as opportunistic omnivores as they utilise different types of food. However, most crustaceans are mainly omnivores with a tendency for herbivory in food habitats. For the P. vespertilio, a crustacean in the family Xanthidae similar to the Guinotellus melvillensis, the most important food source was algae which was obtained by scrubbing the encrusted coralline substratum, with red algae (Rhodophyta) being the most common species to be consumed. The P. verspertilio also feeds on brittle stars, gastropods and bivalves, which displays the range of food sources that the family Xanthidae can consume.