Yang researcher Md Jayedul Islam recorded a
new species of giant guitarfish, Glaucostegus younholeei sp. nov., with his teacher that is
described from 13 specimens, 730933 mm total length, collected from fish
landing center of Bangladesh Fisheries Development Corporation in Cox's
Bazar district of Bangladesh. The new species is distinguished from
congeners in having the following combination of characters: Body
brownish or greyish in color with a narrowly wedge-shaped disc, and long
narrow bluntly pointed snout (angle 3140°), and broad oblique nostrils
with the narrow anterior opening. Nostrils about half of the mouth
width, subequal (0.981.33) to internasal width; ~5557 nasal lamellae;
anterior nasal flaps slightly penetrating into internasal space, their
interspace 2.20 2.61 in length of the posterior nasal aperture. Orbit
very small in adults, diameter 8.1911.62 in preorbital length, 2.252.69
in interorbital space. Rostral ridges almost joined along their entire
length; margin of cranium sharply demarcated before eyes. Spiracular
folds very short and widely separated. Skin rough, densely covered with
small denticles, more coarsely granular on the dorsal surface than
ventrally, enlarged between orbits and in a distinct band between nape
and first dorsal fin. Tail relatively longer, length 1.151.48 in disc
length; dorsal fins narrowly spaced, interspace 1.322.11 in base length
of the first dorsal fin. Clasper length in adult male 4.375.70 in total
length. Phylogenetic analysis of DNA barcode sequences also shows the
clear divergence of Glaucostegus younholeei from other congeneric
species obtained from GenBank. A key is provided to the 8 known members
including new species of the genus Glaucostegus.
Citation : Habib KA, Islam
MJ. Description of a new species of giant guitarfish, Glaucostegus
younholeei sp. nov. (Rhinopristiformes: Glaucostegidae) from the
northern Bay of Bengal, Bangladesh. Zootaxa. 2021 Jun
29;4995(1):129-146. doi: 10.11646/zootaxa.4995.1.7. PMID: 34186813.
