The Shallow-water Crinoid Fauna of Lakshadweep Atolls, North-western Indian Ocean Author Mohammednowshad, B. Department of Science and Technology, Kavaratti- 682555, Union Territory of Lakshadweep, India. & School of Ocean Science and Technology, Kerala University of Fisheries and Ocean Studies, Panangad, Kochi, 682506 Kerala, India. Author Idreesbabu, K. K. Department of Science and Technology, Kavaratti- 682555, Union Territory of Lakshadweep, India. Author Parameswaran, Usha V. Centre for Marine Living Resources & Ecology, Kendriya Bhavan, Kakkanad, Kochi- 682 037, Kerala, India. Author Messing, Charles G. Nova Southeastern University, Halmos College of Natural Sciences and Oceanography, 8000 N Ocean Drive, Dania Beach, FL 33004 USA. Author Sureshkumar, S. School of Ocean Science and Technology, Kerala University of Fisheries and Ocean Studies, Panangad, Kochi, 682506 Kerala, India. text Zootaxa 2020 2020-06-08 4789 1 247 265 journal article 10.11646/zootaxa.4789.1.9 1175-5326 3884945 376263E2-07B2-4B4B-A8E3-C718FE0FC969 Heterometra A.H. Clark, 1909d Type species .— Antedon quinduplicava Carpenter, 1888 . Diagnosis .—A genus of Himerometridae with more than ten arms in fully developed individuals; cirri moderately long with aboral tubercle or spine on distal segments and terminal claw always strongly curved; distal cirrus segments usually shorter than proximal, or both distal and proximal cirrus segments short; proximal brachial pinnules increasing in length and robustness from P1 to P3; enlarged proximal pinnules elongated, slender or rather stout, smooth or with basal keel, or with distal segments each bearing spines or flange-like projection (A.H. Clark, 1941 ). Remarks.— Heterometra currently includes 27 accepted species. However, eight are known from only three or fewer specimens (four from one specimen each), and several are distinguished on the basis of minor morphological, often apparently ontogenetic, differences (e.g., arm number, cirrus and proximal pinnule length, or proportions of cirrals or pinnulars) (A.H. Clark, 1941 ; Messing & Tay, 2016 ).