A newly discovered species of crab named after an Indian university 

What comes to your mind when you hear about crabs? Do these crawlies give you jitters? Well, that’s understandable. They can be quite intimidating, regardless of their size. However, these crustaceans can be quite delicious. That’s why they are the part of seafood menus all across the globe. There are over 7000 species of crabs. Yes, that many! However, there are only 10 to 20 of those that are suitable for humans to eat.  

Here’s an interesting development in the world of crabs. A fresh species has been discovered recently in the mangroves of Parangipettai, located near the Vellar River estuary in the Cuddalore district of Tamil Nadu. While crabs can survive in different kinds of marine ecosystems, be it oceans, seas, rivers, or lakes, this one has been categorised as an estuarine crab (because it was found near an estuary!).  

Okay, so what name was given to this brand-new crab species? Pseudohelice annamalai. Is the name Annamalai sounding familiar to you? Well, it is the name of a famous Indian university called Annamalai University located in the same state. The naming of the crab recognises almost a century’s contribution of the university in the field of education and research. In fact, this latest discovery can be credited to scientists based at Centre of Advanced Studies (CAS) in Marine Biology, a department of Annamalai University, who were also joined by researchers of National Chung Hsing Univeristy, Taiwan. These findings have also been published in the latest issue of the scientific journal named Zoological Studies.  

Here’s what is known so far about this new species of crab. For starters, it is only the third belonging to the genus, Pseudohelice. So far, only two other species namely Pseudohelice subquadrata and Pseudohelice latreilli had existed. Moreover, this new species is only native to the Indian subcontinent, specifically the region east of Indian Ocean. This was also the first ever estuarine crab tracked down in high intertidal areas of Tamil Nadu. In fact, the crab specimens were unearthed along with mud and sand sediments from the artificially planted mangroves spreading across five hectares along the northern shores of the Vellar River, especially from two distinct zones, Rhizophora (towards the estuary) and Avicennia (towards the land in the intertidal region).  

Pseudohelice annamalai can be distinguished easily, thanks to its unique colour that’s somewhere between dark purple and dark grey, with brown or white patches on the posterior (carapace) and light-yellow legs and claws (chelipeds). It is rather small and has a diameter of 20 millimetres. They prefer to live in mangroves by simply making burrows with a depth of 25 to 30 centimetres, that are in turn branched with larger pellets around the mouth. It is a non-aggressive species but can move with high speed, much like other intertidal crabs. So far, as many as 17 intertidal crabs have been traced in the region.  

Further research will be conducted with the specimens at CAS’s crustacean research laboratory. Interestingly, a holotype of the new species will be sent to the Kolkata branch of Zoological Survey of India soon, to be part of the national repository.