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
Dichrometra
A.H.
Clark, 1909d
Type
species.—
Alecto flagellata
Müller, 1841
.
Diagnosis.—
A genus of
Mariametridae
with centrodorsal discoidal, with aboral pole flat, slightly concave or convex; brachitaxes laterally separated and aborally rounded to closely apposed and flattened laterally; adambulacral processes absent; cirrals <40; distal cirrals smooth, or with aboral keel, or blunt or sharp aboral spine; P2, or P2 and P3, larger and longer than both P1 and following pinnules, and tapering distally to slender, often flagellate tip; either P2 or P3 longest and stoutest, or of similar length and strength; enlarged oral pinnules with articular facets not reduced or modified, proximal segments carinate or not, and with LW of middle pinnulars at most 2.0; P2 usually of 20 or more pinnulars (maximum 40); up to 50 arms (usually 20–40) (modified from
Rankin and Messing, 2008
;
Taylor
et al.
, 2017
).
Remarks.—
Taylor
et al.
(2017)
synonymized
Lamprometra
A.H.
Clark, 1913c
, and
Liparometra
A.H.
Clark, 1913c
, under the senior
Dichrometra
. The three genera had been distinguished on the basis of differences in the relative lengths and robustness of P2 and P3.