Not just a
huge collection of
Elasmodiver.com contains images of sharks, skates, rays, and a few
chimaera's from around the world. Elasmodiver began as a simple web
to help divers find the best places to encounter the different
species of sharks and rays that live in shallow water but it has
slowly evolved into a much larger project containing information on
all aspects of shark diving and shark photography.
now more than 10,000 shark pictures and sections on shark
evolution, biology, and conservation. There is a large library of
reviewed shark books, a constantly updated shark taxonomy page, a
monster list of shark links, and deeper in the site there are
numerous articles and stories about shark encounters. Elasmodiver is
now so difficult to check for updates, that new information and
pictures are listed on an Elasmodiver Updates Page that can be
Dasyatis matsubarai. Some
scientists consider D.multispinosa to be a synonym.
The pitted stingray has a rhomboid disc
with a mildly convex leading edge with a bluntly rounded snout. The
trailing edges of its pectoral fins are more noticeably convex. The
dorsal surface of the body disc is uniformly dark grey with a line
of small white spots (small pores ringed in white) on each pectoral
fin running diagonally from midway along the anterior margin to the
base of the tail. In mature adults, a row of tubercles run along the
snout, back and tail (anterior to the first tail spine).
Ventral surface of disc white with a distinctive W
shaped groove posterior to 5th gill slit.
Upper surface of tail has 1-3 stinging spines.
Ventral finfold on tail shallow and roughly half as long as disc
length. When intact, tail terminates in a thin caudal filament.
Maximum disc width 1.2m.
Found from the surface to at least 60m.
Generally caught between 40-60m. Demersal on sandy substrate but a
specimen from the Sea of Japan was caught near the surface over
3000m of water suggesting that this species may be semi-pelagic in
Abundance and Distribution:
Restricted to the northwest Pacific.
Relatively common around Honshu and Hokkaido Islands in Japan. Also
recorded from South Korea and Vladivostok in western Russia.
Unknown. Presumably benthic invertebrates
and small fishes.
Little historical catch data
is available for the pitted stingray therefore it is listed as 'Data
Deficient' by the IUCN at this time. However, this species is
captured as bycatch in longline, coastal gillnet and set-net
fisheries within its range. It is often captured by set-nets and,
when caught, the species is retained, landed and marketed. Stingrays
are among the dominant batoid components of landings in Japan,
however, the relative importance of species on a regional basis is
poorly known and species-specific landing data are virtually
non-existent (H. Ishihara, pers. obs. 2007).
Ito, Chiba Prefecture,
Japan. This specimen was released from fishing bycatch.
There are two other
species of stingrays caught around Honshu Island in the Sea of
Japan. The red stingray Dasyatis akajei is the most common. It has a
reddish brown dorsum with a more pointed snout than the pitted
stingray and lacks white spots.
Reaction to divers:
The pitted stingray generally lives in water too
deep for observation by scuba divers but it may be encountered by
divers venturing onto the sand in deep water at dive sites on the
south side of Honshu in Japan. Try contacting dive shops on the Izu
and Chiba Peninsulas for more information.
References and Citations:
Compagno, L.J.V., Ishihara, H., Tanaka, S. &
Orlov, A. 2009. Dasyatis matsubarai. The IUCN Red List of
Threatened Species. Version 2015.1. <www.iucnredlist.org>.