Abdul Wahab Khan
Panaji: A detailed re-examination of preserved museum specimens collected from the mangrove ecosystems of Goa, Maharashtra and Karnataka has led to the discovery of a new species of grapsoid crab, Chhapgarus ngankeeae.
Described by Dr Sameer Kumar Pati of the Zoological Survey of India (ZSI), Kolkata, in a study published on March 9, 2026, in the journal Marine Biology Research, the discovery points to the ecological significance of India’s west coast mangroves and demonstrates the value of museum collections in uncovering hidden marine biodiversity.
The new species was identified after Dr Pati re-examined crabs preserved in the National Zoological Collections that had long been misidentified as Pseudograpsus intermedius (now Chhapgarus intermedius).
The primary reference specimen, or holotype, was originally collected from beneath a stone in the muddy backwaters of the Galgibag River in Goa. Stereo microscope examination revealed a unique combination of anatomical features distinguishing it from
all known species.
Named Chhapgarus ngankeeae in honour of the late Professor Ngan Kee NG, one of the world’s foremost crab taxonomists, the species also pays tribute through its genus name to Indian marine biologist Dr Boman Framji Chhapgar for his contributions to the study of Indian
marine crustaceans.
Measuring about 1.6 centimetres across its squarish, brown, hairy carapace, Chhapgarus ngankeeae possesses several distinct characteristics. The male features a narrower abdomen, with the second and third abdominal
segments equal in width and a telson as broad as it is long. Its most
defining feature is the structure of the first gonopod, which has a hardened tip bearing two unequal lobes separated by a V-shaped constriction – an anatomical fingerprint that confirmed it as a new species.
Dr Pati noted that the discovery underscores the need for further surveys of mangrove ecosystems along the west coast, where additional undescribed species may remain hidden.
