tusoteuthis is a genus of cretaceous cephalopod molluscs .

one species , t. longa , has been identified so far , and examination of gladius remains has yielded an estimated mantle length close to or equal to that of the modern giant squid .

recent studies suggest a closer relationship to the vampire squid than the modern-day giant squid .

tusoteuthis is assumed to have preyed on other cephalopods , fish , and possibly even small marine reptiles .

despite its size , which was around 20 to 35 feet ( 6 to 11 metres ) long with tentacles fully outstretched , tusoteuthis was still preyed on by other animals , especially the many , various predatory fish of the western interior seaway .

a fossil of the predatory aulopiform , cimolichthys nepaholica , was found with the gladius of t. longa in its gullet .

the back portion of the gladius was in the stomach region , while the mouth of c. nepaholica had remained opened , suggesting that the fish had died in the middle of swallowing the squid , tail first .

researchers strongly suspect that as the fish was swallowing tusoteuthis , the head and/or tentacles remained outside the mouth , thus blocking the gills of the fish , and suffocating it as it swallowed its prey .

tusoteuthis

admincheat spawndino
blueprint ' / game / primalearth / dinos / tusoteuthis / tusoteuthis _ character _ bp . tusoteuthis _ character _ bp '
500 0 0 35
similar to mosasaurus , the tusoteuthis dislikes shallow water and will de - aggro .
unlike other passive tames , taming affinity is not reset when the tusoteuthis takes damage .
ark insight ! - = - which is better ? mosasaurus v . s tusoteuthis !
the tusoteuthis is a massive , aggressive squid found in the depths of the oceans . in battle , the tusoteuthis can grab its prey and knock it unconcious , siphoning its blood to gain health . once tamed , the ink from a tusoteuthis can be used as a constant oil source . some survivors choose to hunt the tusoteuthis for its oil .
using the ( pc ) , ( ps4 ) , ( xbox one ) , the tusoteuthis can pick up another creature with its tentacles . while holding a non - friendly target , the tusoteuthis will constantly inflict torpor until the target is unconscious . note that the tusoteuthis cannot hold an unconscious target .
the tusoteuthis ' s taming method differs from most creatures . please ignore its interval and time calculations .
the tusoteuthis ( too - so - too thiss ) is an aquatic creature in ark : survival evolved .
one of the major benefits of taming tusoteuthis is harvesting its ink . unlike normal ink , tusoteuthis ' ink is very oily , and can even be refined into fuels such as gasoline . between that and tusoteuthis ' distinctive capability to grab & carry large creatures underwater , it makes for an excellent aquatic tame , despite its slower speed .
the tusoteuthis
does not want to be tamed right now
unless it has a creature within its clutches .
tusoteuthis attack can reach far onto the shore and decimate penguin populations in seconds . gathering large amounts of polymer .
tusoteuthis cannot sprint while holding another creature , keep this in mind when using it to transport other friendly tames .
left : a painting of tusoteuthis in a diorama at the sternberg museum of natural history in hays , kansas .
this section displays the tusoteuthis ' s natural colors and regions . for demonstration , the regions below are colored red over an albino tusoteuthis . the colored squares shown underneath each region ' s description are the colors that the tusoteuthis will randomly spawn with to provide an overall range of its natural color scheme . hover your cursor over a color to display its name and id .
with a high armor saddle . stimulants may also be required for taming higher level tusoteuthis , as an unconscious carbonemys is of no interest to the tusoteuthis . the lower the durability of the carbonemys and the higher the dps of the tusoteuthis : the more carbonemys that may be required or sacrificed . other high durability tames also work , but anything that requires oxygen is not recommended .
however , tusoteuthis will now eat regular meat and raw fish meat . it does not require black pearls for food when domesticated .
using the ( pc ) , ( ps4 ) , ( xbox one ) , the tusoteuthis swipes its massive tentacles at the target .
tusoteuthis vampyrus is a very aggressive water predator . approximately 30 feet long , tusoteuthis is a terror of the deep . once it grabs its prey , it slowly crushes it into submission while using the talons on its tentacles to siphon and drink the victim ' s blood !
* rank of the base stat of the tusoteuthis vs . all other creatures . ( rank # 1 in health = highest health creature . )
a monstrous relative of the vampire squid , tusoteuthis bears a closer resemblance to giant squids , but is much more terrifying than its timid kin . tusoteuthis has powerful tentacles with hooked suckers , capable of drawing blood and keeping even a megalodon from escaping a horrible fate . a parrot - like beak hides in the center of the writhing mass , ripping flesh , shell , and bone into easy - to - swallow bits . tusoteuthis also possesses the ability to spray an oily ink if it is in danger . fearing only the mosasaurus , tusoteuthis is a true terror of the deep .
when possible , try to steer the tusoteuthis away from terrain - it is currently possible for its grab to release creatures / players under the ground .
on the center , tusoteuthis can rarely spawn in the pool at the bottom of the waterfall under the land bridge connecting redwoods to the snowy grasslands .
the tusoteuthis on release was originally supposed to be much smaller , but on a last minute change was changed to be the size it is today .
while holding a target , the tusoteuthis will constantly inflict torpor , until the target is unconscious , making it the most efficient knock - out aquatic taming mount . note that the tusoteuthis cannot hold an unconscious target , so the mount will let go of the tame as soon as it ' s tranquilized .
similar to polymer farming , the tusoteuthis ' reach and aoe allows it to harvest cnidaria with impunity , making it a good bulk harvester of bio toxin .
using c ( pc ) , ( ps4 ) , ( xbox one ) , the tusoteuthis releases a large ink cloud to completely obscure vision for a limited time .
tusoteuthis is found only in very deep water , where it swims about at a slow pace . if it spots the player or a tamed creature , it will begin to move itself towards the player or said creature and attack it . because of the unique body plan of cephalopods , a tusoteuthis must turn itself around to strike with its tentacles .
while carrying a creature with its tentacles and using the ( pc ) , ( ps4 ) , ( xbox one ) , the tusoteuthis will crush the target for considerable damage .
right : a field shot of a partial squid pen of tusoteuthis longa that i collected in may , 2010 . a fragment of a inoceramid shell was laying across the gladius .
this section describes how to fight against the tusoteuthis . generally the squid is a very strong enemy , a confrontation should be avoided if you ' re not sure you can win .
tusoteuthis is a terrifying opponent for several reasons . firstly , its grab slowly renders its victim unconscious , so death isn ' t the only concern . secondly , its vampiric blood drain instantly revitalizes it , even during combat . finally , if tusoteuthis is losing the fight , it sprays a cloud of ink into the surrounding water , blinding its attackers to cover a sneaky escape .
you can also use another tusoteuthis to fight it . focus mainly on melee damage , with a little health . swim up to the tusoteuthis and start attacking it . it will try to grab you , but it is not able to . keep attacking it until it tries to flee . because the tusoteuthis has a wide turning radius , you can keep hitting it as it tries to turn . if it is a lower level , you should be able to kill it before it gets away . if it gets away , follow it . tamed tusoteuthis have double the movement speed of wild ones , so you should be able to catch it . as long as the wild squid is near the ground , it will probably run into rocks , where you can kill it .
server admins can use this region information in the console command
cheat settargetdinocolor < colorregion > < colorid >
. for example ,
cheat settargetdinocolor 0 6
would color the tusoteuthis ' s
body highlights
magenta .
in ark : survival evolved , the tusoteuthis eats 50 black pearls , 30 cooked prime meat , 20 raw meat , 30 cooked prime fish meat , 30 cooked meat , 20 raw fish meat , and 30 cooked fish meat .
tusoteuthis was a cretaceous relative of the modern vampire squid - which is likely the inspiration for its blood - sucking tendencies described in the dossier ( although it ' s worth noting that vampire squids don ' t actually drink blood . )
tusoteuthis was native to the western interior seaway , an ocean that split north america in half during the late cretaceous . despite being comparable in size to modern giant squid , it was still far from the top of the local food chain .
fast forward to 2012 . . . . trish and dan came back to kansas to see if we could repeat our earlier success . . . first day , no luck but by noon of the second day , we had another nice specimen of tusoteuthis longa .
right : an artist ' s reconstruction showing the location of the squid pen within the body of the squid , and an artist ' s conception of what the late cretaceous squid , tusoteuthis longa logan may have looked like ( exhibits - sternberg museum of natural history ) .
nicholls , e . l . and isaak , h . 1987 . stratigraphic and taxonomic significance of tusoteuthis longa logan ( coleoidea , teuthida ) from the pembina member , pierre shale ( campanian ) , of manitoba . journal of paleontology 61 ( 4 ) : 727 - 737 , 5 figs .
the evidence of bite marks in some squid pens shows that squid were eaten by many predators including fish and mosasaurs ( stewart and carpenter 1990 ) . click here for a picture of a very large tusoteuthis longa fossil from the pierre shale in the museum of natural history at the university of kansas .
left : a specimen of large ( 1 . 5 m ) cimolichthys nepaholica ( ucm 29556 ) from the redbird shale of wyoming that died trying to swallow a tusoteuthis longa squid . the rachis of the squid is plainly visible inside the ribs of the fish . photo copyright © 2012 by trish weaver . scale = 30 cm .
left : tusoteuthis , a ' giant ' squid that lived in the western interior sea , may have been as long as 25 ft . ( 7 . 5 m ) , although there is little or no proof of their size because so little of their body is preserved . in any case , it probably wasn ' t nearly as large as shown in this dramatic painting in the university of kansas museum of natural history .
while riderless , the tusoteuthis will not wait long to let go of your creature - making a team of two the safest option , as the distraction ' s rider can remain mounted until the creature is fed and then dismount themselves and swim up . if you do attempt to solo tame , flippers are recommended for speedy getaways . make sure your tame is on passive and set to follow , and if it survives the feeding it will swim up to safety the moment the squid lets go .
name : tusoteuthis . phonetic : too - so - te - ew - fiss . named by : logan  -  1898 . classification : mollusca ,  cephalopoda ,  cephalopoda ,  coleoidea ,  vampyromorphida ? species : t .  longa ( type )  . diet : carnivore . size : estimates vary and range from about 6 to 11 meters long ( based upon giant squid and if measured from the mantle to the tips of the tentacles )  . known locations : canada ,  manitoba  -  pierre shale formation . time period : campanian of the cretaceous . fossil representation : several specimens of the gladius ( shell inside of the mantle )  .
further reading -  statigraphic and taxonomic significance of tusoteuthis longa logan ( coleoida ,  teuthida ) from the pembina member ,  pierre shale ( campanian )  ,  of manitoba .  journal of palaeontology ,  61 ( 4 ) 727 - 737  -  e .  l .  nicholls & h .  isaak  -  1987 . -  cretaceous fish predation on a large squid .   -  evolutionary paleobiology of behaviour and coevolution ,  195 - 197 .   -  e .  g .  kaufman  -  1990 . -  examples of vertebrate predation on cephalopods in the late cretaceous of the western interior .   -  evolutionary paleobiology of behaviour and coevolution ,  203 - 207 .   -  j .  d .  stewart & k .  carpenter  -  1990 .
keeping cephalopods in captivity ceph care equipment list before you get an octopus as a pet . . . octopus basics - keeping an octopus as a pet keeping an octopus octopus bimaculoides care sheet ceph care , past and future ink ' s story ( o . bimaculoides ) before you buy a cuttlefish . . . . cuttlefish basics - keeping a cuttlefish as a pet keeping and breeding dwarf cuttlefish sepia bandensis : husbandry and breeding tankmates : it works until it doesn ' t o . chierchiae babies ( lpso ) packing and shipping cephalopods diy skimmer
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by phil eyden - 2003 note : phil welcomes discussion on this article in the cephalopod fossils forum . introduction
, the giant and colossal squid , are enigmatic and awe inspiring animals . very little is known about the lifestyle of these spectacular animals , despite the examination of numerous corpses of
, much of what we know about the animals ' behaviour and lifestyle boils down to educated speculation . what is not so well known is that these modern squid were not the first giant squid in the earths
, giant turtles and plesiosaurs about 80 million years ago during the late cretaceous period . imagine the difficulties of reconstructing these ancient animals when all we have to go on are fragmentary fossilised remains of the pens , or
providing strengthening and support for the mantle , the main body of the squid .
alopods ; soft bodied parts , in those rare cases of exceptional preservation , are not generally diagnostic or much use in determining species interrelationships . unfortunately the
alopods to imagine how much we have lost and will never be able to reconstruct with these ancient animals .
is the most common specimen and this is known from just 25 examples ( 1987 figure ) . prehistoric giant squid remains are known purely from the shallow western interior seaway , which was a vast sea that bisected
the early cretaceous following a period of rapid global warming , sea floor spreading and rise .
this seaway is thought to have been very shallow , generally less than 600 feet deep , with a flat muddy bottom .
each of these species was described on the basis of a single specimen . all these animals are known from remains of the
alone , the stiffening rod running the length of the mantle , the different species were known from variations in the size and form of this cuttlebone until recent revisions grouped all these animals together under one genus .
member of the pierre shale that lies immediately above the chalk at a date of 79 million years old .
was described by h . w . miller in 1957 on the basis of three specimens found in the late thirties in the
1977 by r . g . green on the basis of one very badly crushed specimen .
and lacked a prominent keel . however , it may be misleading to identify these large squid as separate animals ; a 1987 paper by
the differences in morphology noted above could be explained as artifacts of preservation , deformations caused by crushing during the process of fossilization and misinterpretation of dorsal and ventral surfaces . the sole specimen of the
to be so badly broken and crushed that any attempt at reconstruction would be largely hypothetical . this theory has now achieved general acceptance ; all recorded examples of
giant prehistoric squid are also known from other parts of the world . at richmond , in queensland , australia a 100 million year old 1 . 3 metre
in her honour . this is currently on display at the richmond marine fossil museum . students in queensland located a contemporary second gladius in 1998 that measured over a meter in length and possibly shows evidence of predation by
taxonomy is still being compiled . the evolutionary history of the orders of squid and other non -
, or pen , and even that is very rarely preserved due to its delicate nature . much of what is currently understood about evolutionary relationships of these animals has not been agreed upon ; there are two or three differing models of the
tree , each new discovery may call for the models to be reworked . the only really well preserved
, and a handful of other lesser known localities . these represent snapshots of biodiversity ; what happened in between them is tantamount to educated guesswork with rare and isolated specimens providing evolutionary clues . most collections in museums are labelled simply as
fossil
a little of the evolutionary history has been determined , even if it is somewhat speculative . it is currently thought that these ancient giant squid were members of the
, the vampire squid . this is in common with many of the jurassic
group that failed to survive the mass extinction at the end of the cretaceous . these palaeololiginidae are well documented in
and was working from a description ; nichols and isaac revised the family to the kelaenidae in 1987 . ( miller had also assigned
lived in the devonian period , possibly over 380 million years ago . as these giants are not believed to be ancestral to
' immediate ancestors makes it impossible to determine when the recent giants arose . the difference between
of preservation and the animals may , in fact be one and the same . the radically different shape of the
may indicate that these western interior seaway squid had a differing external appearance in the shape of the mantle , perhaps broader at posterior end of the animal .
of the six manitoba specimens measures at just over 1 . 2m in length but the sixth and most recently recovered specimen is larger but incomplete , and would have belonged to an animal which was a third larger again ; it is unknown what the maximum size adult animal would have been . if one assumes a consistent growth rate maintaining the same proportions and ratios , then this sixth
would have been approximately in the order of 1 . 8m if complete , and there is no evidence to suggest that this was fully grown . at the time of writing ( may 2004 ) , another
measuring six foot ( 1 . 8m ) is being prepared for display at the north dakota heritage centre at
can be taken to be 2 . 15m ( one specimen had a mantle length of 2 . 25m and the
was of comparable size , if a little shorter . with so few specimens to work from we cannot be sure what was the maximum size attained by
, but the standard length ( tip of arms to tip of mantle ) may have been of a similar size . we may be looking at an adult
have this feature . arm hooks are likely , but suckers do not fossilise and their presence cannot be determined .
and the ancient giants is that of lifestyle as they lived in very different environments .
as it lived in shallower conditions with more available light . there is some indirect evidence that these
, an important marine predator in the seaway , and not likely to have been a deep diving animal .
probably would have constituted a major dietary component for fish and marine reptiles throughout the western interior seaway . the evidence for this comes from coprolites ( fossilised faeces ) , damaged
a total of five specimens of coprolites have been collected from separate locations ( 1987 figure ) . two of these coprolites were collected from a
, one of which also contains fish teeth and vertebrae . from the coprolites alone it is difficult to determine what animal was eating
but from the small size of these coprolites researchers have concluded that this was probably some form of large predatory fish ( largest is 4 . 78cm x 3 . 82cm ) .
, it is believed that this is probably the stomach contents of a large carnivore of indeterminate origin . this specimen measures 26 . 7cm x 16 . 5cm x 4 . 4cm is currently held at
, the predators are identifiable . a spectacular discovery of a partial specimen of the predatory fish
that had been swallowed whole , and was so large it had probably choked the fish to death .
probably related to the salmon and resembling a barracuda in form with conical and widely spaced teeth suitable for puncturing flesh . it is believed to have been an open water predator adapted for sustained swimming and rapid bursts of speed and was a long - ranging and common species in the western interior seaway . this particular specimen of the fish is incomplete , the preserved section measures 152cm in length but it contains a nearly complete 66cm
stuck in the ribcage in the area of the shoulder of the fish . the
projects towards the mouth where it appears to be broken below the left gill cover . it seems likely that
ripping through the skin of the squid and causing interior gill damage or the size of the body of the squid forcing the gullet to remain open . this amazing specimen is currently held at the university
is composed to splay apart and cause some severe twisting to the structure . the punctures are widely spaced , the distance of 31cm between two of the punctures has been interpreted as an oblique angle of attack by the
and mantle to sink to the sea floor . this specimen was collected from the sharon springs member of the pierre shale , and it is thought that the predator was probably
potentially the largest fossil coleoid to be discovered to date was published in january 2006 by kazaushiga tanabe , yoshinori hikida and yasuhiro iba . it consisted of one half of an enormous set of jaws discovered in late cretaceous campanian ( 83 - 71 mya ) sediments at wakkaweenbetsu creek , nakagawa town , hokkaido , japan . the fossil was composed of a black phosphatic material and was contained inside a calcareous nodule . included with the specimen were numerous bivalves and specimens of the heteromorphic ammonite
. the fossil came from the upper yezo group of mudstones , ' yezo ' being an old name for hokkaido . the fossil is an upper jaw that measures 97mm in length and is 22 . 5mm wide at its maximum point . it has a very sharply pointed rostrum that is angled acutely , and both the inner and outer lamellae are present .
. as a result of this and from a physical comparison of the shape of the rostrum and wings , the authors determined that the specimen is closest to the sub - order oegopsina . the authors then attempted to estimate a total size for the animal , by examining the ratio of the maximum length of the upper jaw ( luj ) to total mantle length ( ml ) in eight extant coleoid species . applying these derived ratios to the fossil jaw and plotting it along with these other specimens , it was concluded that the mantle length was probably akin to
not only in overall size , but in shape , and structure . it differs in that the crest margin is more convex in shape and has more prominent growth lines on the inner lamella .
, that would have been present in late cretaceous northwest pacific along with many small ammonoid and nautiloid shelled cephalopods . the jaw is currently housed at the nakagawa museum of natural history .
was probably a major component of the ecosystem of the western interior seaway and a favoured prey item of assorted marine predators . it probably lived in shallow depths and would have been a fast moving muscular squid as demonstrated by its robust
, it would have thrived in a very different and extremely biologically active environment .
2 ) north dakota heritage centre at bismarck ( expected late 2004 ? ) .
3 ) natural history museum of los angeles county , california as part of the
savage ancient seas
exhibit .
fuchs , d . , keupp , h . , and engeser , t . , new records of soft parts of
kauffman , e . g . , cretaceous fish predation on a large squid .
tanabe , k . , hikida , y . , and iba , y . , two coleoid jaws from the upper cretaceous of hokkaido , japan . journal of paleontology 80 ( 1 ) 138 - 145 , 2006 .
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these values may differ with what you see in - game or written elsewhere . but that is what the dossier says .
this dossier section is intended to be an exact copy of what the survivor helena , the author of the dossiers has written . there may be some discrepancies between this text and the in - game creatures .
1 percentages are based on the value of the stat the moment the creature was tamed ( after taming effectiveness ) 2 the absolute base damage is shown here instead of the percentage . 3 wild creatures do not level up movement speed 4 torpidity increases every level on wild creatures , but can not be increased once they are tamed .
for a comparison of the stats of all creatures , see base creature statistics .
for an explanation of exactly how the levelup calculation works , see creature stats calculation .
type in values of a wild creature to see on which stats it ' s emphasized . green values on a high - level creature are very good for breeding . if you have already tamed your creature you can try to recover the breeding - stats with an external tool . [ 1 ]
note that after the creature is tamed it gets bonuses on some stats depending on the taming effectiveness . this makes it hard to retrieve the levels on a tamed creature , so this tool is only for wild ones , but gives a first impression , how well the stats are distributed .
it will eat up to 50 of an individual food item in a single consumption . taming effectiveness is lost per consumption not per item , and is at a reduced rate compared to other tames in any case .
it can eat at 90 % of its maximum food , regardless of how much food what it ' s being fed will restore ( factoring the above ) .
the taming affinity ( progress ) gained for food types other than black pearls is only 10 % of the value derived by other tames ( e . g . 15 from prime meat instead of 150 ) , and so at least 10 should be fed at a time to have a comparable taming time to other creatures . due to the exceptionally low affinity from individual items , they have been omitted from the table below , which consequently omits raw prime meat and raw prime fish meat entirely .
please ignore the feeding interval and taming time data ( below ) . due to being able to eat when at 90 % of its maximum food , the minimum feeding interval is 177 . 5 seconds [ 2 ] plus 14 seconds per food level . [ 3 ]
remember that a passive tame ' s first feeding interval is always slightly longer than this value .
this cannot be known until after taming , but adding 14 % of the creature ' s level would produce average results .
note that the values are for optimal cases , always bring extra supplies ! for a level - dependent count of resources needed , try an external taming calculator .
note that 50 black pearls will still restore up to 1500 food regardless of the creature ' s current food when fed , and so starve taming will actually take longer as the full 1500 food will need to deplete per required consumption ( compared to allowing 10 % to deplete each time ) .
dismount then approach the creature ' s beak with 50 black pearls within your last inventory slot . be aware of the weight of black pearls .
swim directly up and out of the deep - water zone . you are not able to re - mount while the squid has your creature held .
after taming , its diet remains the same ( black pearls , meat and fish ) .
a low - level tuso is no match for a mid - to - strong tamed plesio or mosa . a high level one will need a very strong mount with a good saddle or a group of powerful sea dinos to be defeated . remember that a ridden tame cannot retaliate when within tuso ' s tentacles . if you ' re going for a pack attack , let the squid grab the dino you ' re riding , as you will be able to watch out for the health and the torpor of your mount and you ' ll have one more source of damage . when it will spray the ink and try to run away get out of the ink cloud , wait for the blinding effect to end and then easily chase your prey .
another method to kill a tuso is luring it into underwater canyon and shoot it from above using crossbow , it will try to attack you but his large hitbox doesn ' t allow it to turn effectively and it will start to turn around randomly , unable to hit you .
ranged weapons can work if used while riding a high - level dino . due to the fast rising of tuso ' s health pool , it ' s advised to use this tactic only on low - level ones .
its high health , good dps , life - draining attacks and grab mechanics make the tuso a deadly enemy . living only in the deepest seas , other animals can join the fight and turn the battle into carnage . try to stay away from the bottom of the sea as the tuso may drop its prey under the ground , thus killing it .
the tuso is vulnerable to packs of dinos due to its aoe , that resembles a long cylinder . this means that it can ' t attack many enemies at once .
using , , , it is usable as an aquatic carrier ( like the megalosaurus and kapro ) for anything up to the size of a rex and mosa , use left click to munch the captured dino or player to death . it cannot grab birds . ( it can grab pelagornis , but it can ' t pull them under the water , not tested with other fliers . )
italics denote creatures that have not yet been released ! see also gallery of dino dossiers .
this page was last edited on 24 june 2018 , at 15 : 36 .
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make sure when encountering this creature , to make sure you ' re tribe member is japanese . he or she would gladly volunteer to be grabbed by the tentacles .
please tell me why it says non - violent . . . because when it grabs u and eats u alive it ' s not very non - violent . . .
they are easier to find while riding a raft , having a monkey on your shoulder , and having a beard . it is recommended to have a big raft that looks like a pirate ship . the ship must have cannons .
just tamed a 150 on an official server . building a trap high off the ocean floor works great just trap it and rotate out 150 tamed turtles hp pumped . took about 2 hours with pearls for the tame . took 50 pearls every 5 - 10 min . happy taming !
basilosaurus ( whale dino ) is immune to the squids grabs . its also immune to jellyfish stings . : )
ok so for those of you actually looking for tips . 1 : it can eat 50 at a time so take 50 with you each time . 2 : it hold mounts only for a little bit so if you can , just hop back on the turtle quickly and swim away till the next feeding 3 : once you tame it beware manta s and anglers as the tuso cannot hit them while they glitch into the head of the squid . it ' s not that hard if you prepare to lose everything and keep trying . it ' s worth it once you do but you will need escorts to help with mantis and anglers such as megaladons .
dododex is an ark taming calculator app for ark : survival evolved ( pc , xbox , ps4 ) . a project by dan leveille .
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giant squid found ! ( 50 - foot - long , washed - up on beach , punakaiki , new zealand , march 1st 2015 . )
squid ( teuthids ) : squid are soft bodied invertebrates ( cephalopods ) that probably occurred in great abundance in the warm oceans during the mesozoic . occasionally , the internal structure ( gladius or pen ) of the squid is preserved . the fossil remains of squid are characterized by long , straight fibers or strands that often appear to be iridescent . squid remains are sometimes mistaken for an unusual fish bone . click here for more information
williston ( 1897 , p . 242 ) was puzzled by fragments found occasionally in the chalk that were of a
glistening fibrous nature .
a specimen collected by h . t . martin ( below ) solved the mystery when it became apparent that the fragments represented a
large cuttlefish , apparently different from any described species . the specimen was about 6 inches wide and a foot long , and preserved a small
sepia bag
( ink sac ) below it .
logan 1898 ( ku 4208 / 113463 ; plate cx , figure 2 ) . note that the species name was corrected for gender to
from the hesperornis beds of the niobrara cretaceous on the smoky hill river by mr . martin .
logan , w . n . 1898 . the invertebrates of the benton , niobrara and fort pierre groups . the university geological survey of kansas , part viii , 4 : 432 - 518 , pl . lxxxvi - cxx .
miller , h . w . , jr . 1968 . invertebrate fauna and environment of deposition of the niobrara ( cretaceous ) of kansas . fort hays studies , science series no . 8 , i - vi , 90 pp .
( fhsm ip - 710 ) in the exhibit at the sternberg museum of natural history . this specimen was collected by marion bonner in logan county . squid pens ( rachis ) are made up of chitin , not bone or cartilage . it is also considered to be the type specimen of
right : the gladius of the type specimen of
enchoteuthis melanae
( fhsm ip - 13049 ) discovered by and named for melanie bonner . this specimen appears to preserve much of the original chitin .
squid pen collected by scott garrett from trego county in 2009 . note that the missing pieces looks suspiciously like the bite marks left by a small shark .
left : four views of a squid pen ( rachis ) that was bitten through by an unknown predator .
early in 2011 , i was contacted by trish weaver , the collections manager of the north carolina museum of natural sciences . she was doing research on fossil squid trying to determine what fossil squid pens were composed of ( chitin , chitinous or what ? ) and was looking for a sample to test . she also wanted to spend some time in the smoky hill chalk , so we made arrangements to spend a day in the chalk and search for a specimen that she could use in her research . neither of us really expected to find a specimen
on demand
but i thought there was a good chance of finding at least a fragment at the site where i had collected a specimen in may , 2011 ( above ) . with that realistic goal in mind , we drove out to the locality early in the morning on july 8 . the weather was actually unseasonably cool and cloudy for kansas in july . . . . a great day to be in the field .
our group included dan lawver , a montana state graduate student , who was also from north carolina . neither of them had ever worked in the smoky hill chalk , so i expected we would spend quite a lot of time just getting used to the chalk and all the inoceramid shell fragments at this locality . about half an hour into our search , dan called me over and said he had found something . as i got closer , he said it was probably a root , but i was still hopeful . as it turned out , he ' d nailed some squid remains almost as soon as he started looking . . .
left : this is the view from where i parked the van on the edge of the exposure . . . . we were in southeastern gove county , about a half mile south of the smoky hill river . the place where the squid remains were found is shown at the upper right of the photograph . the canyon is about half a mile wide at this point and is mostly between hattin ' s marker units 2 and 3 stratigraphically ( late coniacian in age ) .
right : here is what dan saw coming out of the side of a gully . . . not much to look at but definitely part of the rachis of a squid . i noted that it appeared to be expanded where it had been broken ( bitten ? ) off and assumed that the expanded portion ( gladius ) was already gone . i ' d soon find out otherwise .
left : i loaned dan my big estwing gp100 pick and let him take the matrix off the the fossil . the chalk was fractured and this part of the job didn ' t take long . . . .
right : once we had most of the overburden off , i got down for a closer look ( actually blowing chalk off the specimen in this photo ) . . . . then i got up on top the exposure and started removing the remaining layers of chalk over the fossil .
left : the first layer came off easily and cleanly . . . i was well off to the side when i started to remove the next layer . . . . and then
oops !
. . . . a big chunk came off with parts of the specimen in it . . . that was when i realized that the fossil was sitting in fractured chalk on a layer of bentonite / volcanic ash . . . bad mistake , but on the good side , it revealed that the gladius was still there , apparently folded over in some way , and it showed us where to dig and not to dig . after kicking myself for a while , i went back to work . . . .
right : here ' s the chunk that came up . . . . the area inside the white oval shows where the remains broke off the main specimen . . . . clean breaks . . . no major damage . i applied some preservative to hold everything in place . . . the other material under the ruler is the pile of bentonite / volcanic ash that created the problem .
left : once we knew where the fossil was in the chalk , we began to cut the size of the block down to reduce the weight . that was when we noticed that the block was fractured and that the squid pen was supported by two different layers of chalk . . . both of which were loose .
right : we decided that the jacket would have to include both layers in order to keep from fracturing the rachis . . . in this photo the exposed portion of the specimen is under the pink cloth . . . note the shattered condition of the chalk at the top of the picture . the blocks holding the specimen were only slightly more solid .
left : once the block was cut down to a minimal size ( using a hand saw ) , it was necessary to clean everything up to prepare it for jacketing .
left : well , maybe one more picture to include dan , the proud discoverer of this specimen . . .
right : after packing the specimen with dampened paper towels for cushioning , trish and dan applied several layers of tin foil to help hold things together . . . .
left : then we proceeded to
get plastered
in the hot afternoon kansas sun . in this case , we used plaster bandages to build up the jacket around the specimen . once the plaster had dried , we slipped a piece of plywood under the jacket . i did not want to turn the jacket over in the field because the chalk around it was unpredictable and the squid pen was really fragile . . .
right : here dan ( right ) and i carry the jacket up the hill to the van .
the specimen will not be prepared for a while , but i will post new photos when they become available . i expect that this specimen would rate with some of the better specimens collected from the chalk in the last 120 years . . . there just aren ' t that many of them around .
right : not much to see while still contained in the matrix . . . just a bit of the gladius .
left : fortunately , we were able to park on the prairie just about the dig site . minimal distance to carry the block of chalk up the hill .
right : the chalk block containing the squid remains , just prior to removal . although we jacketed our specimen in 2011 , the chalk was solid around this one , and did not require the extra effort .
the project has proceeded to the point of submitting an abstract for the 2012 meeting of the geological society of america .
everhart , m . j . 2005 . oceans of kansas - a natural history of the western interior sea . indiana university press , 322 pp .
green , r . g . 1977 . niobrarateuthis walkeri , a new species of teuthid from the upper cretaceous niobrara formation of kansas . journal of paleontology 51 ( 5 ) : 992 - 995 .
hoganson , w . 2006 . dinosaurs , sharks , and woolly mammoths : glimpses of life in north dakota ' s prehistoric past . journal of the northern plains 73 ( 1 - 2 ) : 60 pp .
larson , n . l . 2010 . fossil coleoids from the late cretaceous ( campanian and maastrichtian ) of the western interior . ferrantia 59 : 78 - 113 .
miller , h . w . , jr . 1957 . niobrarateuthis bonneri , a new genus and species of squid from the niobrara formation of kansas . journal paleontology 31 ( 5 ) : 809 - 811 .
miller , h . w . , jr . 1968 . invertebrate fauna and environment of deposition of the niobrara ( cretaceous ) of kansas . fort hays studies , n . s . , science series no . 8 , i - vi , 90 pp .
stewart , j . d . 1976 . teuthids of the north american late cretaceous . kansas academy of science , transactions 79 ( 3 - 4 ) : 74 ( abstract ) .
williston , s . w . 1897 . niobrara cretaceous . the university geological survey of kansas 2 : 237 - 246 .
stewart , j . d . and carpenter , k . 1990 . examples of vertebrate predation on cephalopods in the late cretaceous of the western interior . pp . 203 - 208 in boucout , a . j . ( ed . ) , evolutionary paleobiology of behavior and coevolution . elsevier , new york .
williston , s . w . 1897 . the kansas niobrara cretaceous , the university geological survey of kansas , 2 : 237 - 246 .


margaritiferidae is a family of medium-sized freshwater mussels , aquatic bivalve molluscs in the order unionoida .

they are known as freshwater pearl mussels , because the interior of the shell of these species has a thick layer of nacre or mother of pearl , and the mussels are thus capable of producing pearls .

margaritiferidae

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( spengler , 1793 ) ( bivalvia : margaritiferidae ) découvertes dans le sud - ouest de la france . malaco 6 : 294–297 .
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( bivalvia : margaritiferidae ) in the chubu - nougu river , nagano prefecture [ in japanese ] . venus . 2008 ; 67 : 61–71 .
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all the phylogenies inferred in this study support the reciprocal monophyly of both ( unionidae + margaritiferidae ) f - and m - type lineages ( fig .
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, a new species of unionacea ( bivalvia : margaritiferidae ) from the mobile - alabama - coosa and escambia river systems , alabama . occasional papers on mollusks . 1983 ; 4 : 299–304 .
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smith d . g . ( 2001 ) systematics and distribution of the recent margaritiferidae . in : bauer g . , wächtler k . ( eds ) ecology and evolution of the freshwater mussels unionoida . ecological studies ( analysis and synthesis ) , vol 145 . springer , berlin , heidelberg
citation : bolotov in , bespalaya yv , vikhrev iv , aksenova ov , aspholm pe , gofarov my , et al . ( 2015 ) taxonomy and distribution of freshwater pearl mussels ( unionoida : margaritiferidae ) of the russian far east . plos one 10 ( 5 ) : e0122408 . urltoken
huff sw , campbell d , gustafson dl , lydeard c , altaba cr , giribet g . investigations into the phylogenetic relationships of freshwater pearl mussels ( bivalvia : margaritiferidae ) based on molecular data : implications for their taxonomy and biogeography . j mollus stud . 2004 ; 70 : 379–388 .
diagrams of the five distinct gene orders detected in unionida . in the female f - type lineage , three gene orders are depicted : unionidae f - type 1 ( uf1 ) , unionidae f - type 2 ( uf2 ) and margaritiferidae f - type 1 ( mf1 ) . in the male m - type lineage , two gene arrangements are shown : unionidae m - type 1 ( um1 ) and margaritiferidae m - type 1 ( mm1 ) . continuous lines indicate different locations of genes between mitogenomes . grey box highlights gene rearrangement region between uf1 and uf2 . yellow boxes indicate main differences in gene arrangement between female and male mitogenomes , trna ( h ) location and rearrangement of atp8 - trna ( d ) region .
stephanie w . huff , david campbell , daniel l . gustafson , charles lydeard , cristian r . altaba , gonzalo giribet ; investigations into the phylogenetic relationships of freshwater pearl mussels ( bivalvia : margaritiferidae ) based on molecular data : implications for their taxonomy and biogeography , journal of molluscan studies , volume 70 , issue 4 , 1 november 2004 , pages 379–388 , urltoken
the family margaritiferidae includes 13 extant species , which are mainly distributed in temperate latitudes of the northern hemisphere [ 1 ] , [ 2 ] , [ 3 ] . smith [ 4 ] provided a detailed diagnosis of the family . recent species are known from north america , europe , northern africa , the middle east , and throughout much of southern and eastern asia [ 2 ] , [ 4 ] . the most ancient margaritiferidae fossils are known from the upper triassic and lower jurassic fluvio - lacustrine deposits in the sichuan , southeastern china [ 5 ] , [ 6 ] . the recent margaritiferids retain the simple , unfused mantle margins from the ancestral palaeoheterodont and several other ‘plesiomorphic’ features ; therefore , these species have been regarded as the basal unionoid family [ 3 ] , [ 7 ] .
the north american , european and northern african margaritiferidae are relatively well studied [ 8 ] , [ 4 ] , [ 9 ] , [ 10 ] , [ 11 ] in contrast to the asian representatives of the family . most of the references for far eastern freshwater pearl mussel populations are from japan [ 12 ] , [ 13 ] , [ 14 ] , [ 15 ] , [ 16 ] . recently , a description of a new japanese margaritiferidae species m . togakushiensis kondo & kobayashi , 2005 was published . this species was separated from m . laevis based on the results of long - term studies , specifically including differences in the host fish preference and genetic and morphological patterns [ 17 ] , [ 18 ] , [ 19 ] , [ 20 ] , [ 21 ] .
manuel lopes - lima , miguel m . fonseca , david c . aldridge , arthur e . bogan , han ming gan , mohamed ghamizi , ronaldo sousa , amílcar teixeira , simone varandas , david zanatta , alexandra zieritz , elsa froufe ; the first margaritiferidae male ( m - type ) mitogenome : mitochondrial gene order as a potential character for determining higher - order phylogeny within unionida ( bivalvia ) , journal of molluscan studies , volume 83 , issue 2 , 1 may 2017 , pages 249–252 , urltoken
shows the topology of the bi - nuc tree ; all other phylogenetic trees figures supplied on request ) . additionally , the monophyly of unionidae ( both f - and m - type ) , margaritiferidae ( f - type ) and all represented unionidae subfamilies are well supported in all inferred mtdna trees , with the exception of the unioninae , for which monophyly was only well supported in the bi - nuc tree . the remaining phylogenetic trees ( bi - aa , ml - nuc and ml - aa ) showed conflicting results regarding the position of the clade comprising
according to kondo & kobayashi [ 18 ] , the adductor muscle scar shape is one of the key features for m . togakushiensis identification . however , according to our data , this feature has a high variability and cannot be used for species identification among studied taxa . in the review of recent margaritiferidae by smith [ 4 ] , this feature was also not mentioned as a diagnostic . the adductor muscle scar shape was not used in the morphological descriptions of other unionoid species [ 10 ] , [ 86 ] , [ 95 ] , [ 96 ] , [ 97 ] .
the dimensions of the shell are the least reliable morphological traits in unionoida , upon which to base a description [ 4 ] , [ 32 ] due to high variability and the dependence on environmental gradients [ 4 ] , [ 33 ] , [ 34 ] , [ 100 ] , [ 101 ] . however , sometimes , the shell dimensions and shape are useful for distinguishing several margaritiferidae species . for example , m . middendorffi has a small shell length ( < 100 mm ) ( fig 10 ) , and m . dahurica has the largest shell length ( up to 196 . 5 mm ) among the far eastern pearl mussels ( fig 5 ) .
the analysis of the mitochondrial coi gene showed that c . monodonta forms a separate clade , which is basal within margaritiferidae . m . dahurica , m . margaritifera , m . middendorffi , m . laevis and m . falcata cluster together in a well - supported clade ( bpp 1 . 00 ) ( fig 2b ) . among these , our bayesian inference strongly supports the sister relationships within two pairs of species , namely m . dahurica and m . margaritifera as the first pair ( bpp 1 . 00 ) , and m . middendorffi and m . laevis as the second pair ( bpp 0 . 97 ) . m . falcata shows a closer affinity to m . middendorffi and m . laevis ( bpp 0 . 93 ) . lastly , the coi phylogeny confirms that m . auricularia and m . marocana are sister taxa ( bpp 0 . 98 ) .
the length of the two newly sequenced mitogenomes of m . marocana , 16 , 001 bp for the female haplotype and 17 , 562 bp for the male haplotype , is within the typical range for each sex - specific haplotype within unionida . the sequenced haplotypes include the 13 pcgs typically found in metazoan mitochondrial genomes , the sex - specific orf described for all unionida mitogenomes with dui system ( breton et al . , 2009 , 2011a ) and 22 transfer rna ( trna ) and two ribosomal rna ( rrna ) genes . the m - type genome is the largest sequenced to date within the unionida . m - type genomes are generally larger than f - type genomes due to the larger size of the pcg cox2 and m - orf in m - type genomes compared with cox2 and f - orf in f - type genomes ( breton et al . , 2009 ) . four intergenic regions were identified in the m . marocana m - type genome between the following gene pairs : nad3–trna ( a ) 106 bp , trna ( h ) –trna ( q ) 411 bp , nd4l–trna ( d ) 255 bp and trna ( d ) –atp8 498 bp . these regions were analysed to search for the m - orf . the results of the blast search ( altschul et al . , 1997 ) retrieved a significant hit with another margaritiferidae m - orf ( margaritifera monodonta , e - value = 4e–34 ) and a fickett test score of 1 . 201 ( fickett , 1982 ; a score > 0 . 95 means the sequence is probably coding ) , suggesting that the m - orf is located in the region between the genes nd4l and trna ( d ) .
genus margaritinopsis accepted as margaritanopsis f . haas , 1910 accepted as margaritifera schumacher , 1815 ( incorrect subsequent spelling )
henderson j . ( 1929 ) . non - marine mollusca of oregon and washington . the university of colorado studies . 17 ( 2 ) : 47 - 190 . page ( s ) : 53 [ details ]
invertebase . ( 2015 ) . authority files of u . s . and canadian land and freshwater mollusks developed for the invertebase project ( invertebase . org ) . [ details ]
( of margaritanidae ortmann , 1910 ) graf , d . ; cummings , k . ( 2007 ) . review of the systematics and global diversity of freshwater mussel species ( bivalvia : unionoida ) . journal of molluscan studies . 73 ( 4 ) : 291 - 314 . [ details ]
( of margaritanidae ortmann , 1910 ) invertebase . ( 2015 ) . authority files of u . s . and canadian land and freshwater mollusks developed for the invertebase project ( invertebase . org ) . [ details ]
( of cumberlandiidae heard & guckert , 1970 ) graf , d . ; cummings , k . ( 2007 ) . review of the systematics and global diversity of freshwater mussel species ( bivalvia : unionoida ) . journal of molluscan studies . 73 ( 4 ) : 291 - 314 . [ details ]
( of cumberlandiidae heard & guckert , 1970 ) invertebase . ( 2015 ) . authority files of u . s . and canadian land and freshwater mollusks developed for the invertebase project ( invertebase . org ) . [ details ]
discover a faster , simpler path to publishing in a high - quality journal . plos one promises fair , rigorous peer review , broad scope , and wide readership – a perfect fit for your research every time .
copyright : © 2015 bolotov et al . this is an open access article distributed under the terms of the creative commons attribution license , which permits unrestricted use , distribution , and reproduction in any medium , provided the original author and source are credited
data availability : data are available from : rmbh - russian museum of the biodiversity hotspots of institute of environmental problems of the north of the ural branch of russian academy of science , arkhangelsk , 163000 , russia . inrec - institute of natural resources , ecology and cryology of the siberian branch of russian academy of sciences , chita , 672000 , russia . zisp - zoological institute of the russian academy of sciences , st . petersburg , 199034 , russia . smf - forschungsinstitut und natur - museum senckenberg , senckenberg - anlage 25 , 6000 frankfurt - am - main 1 , germany .
funding : this study was supported by the federal agency for scientific organisations ( no . 0410 - 2014 - 0028 ) , the ural branch of russian academy of sciences ( nos . 15 - 12 - 5 - 3 and 15 - 2 - 5 - 7 ) , grants from the president of russia ( no . md - 6465 . 2014 . 5 and мк - 4735 . 2015 . 4 ) and the russian foundation for basic research ( nos . 14 - 04 - 98801 and 15 - 04 - 05638 ) and the ministry of science and education of russia ( no . p362 ) . the funders had no role in study design , data collection and analysis , decision to publish , or preparation of the manuscript .
thus , the available information on the asian freshwater pearl mussels is limited . their taxonomy is not completely clear and reliable data on the species’ ranges are sparse . however , freshwater pearl mussels are extremely demanding regarding habitat quality and can exist only in a narrow range of environmental conditions [ 11 ] . the majority of these species are listed by iucn as endangered or vulnerable taxa [ 8 ] , [ 9 ] , [ 10 ] , [ 11 ] , [ 40 ] . freshwater mussels have experienced one of the highest rates of extinction of any group of organisms in the past 100 years [ 41 ] . therefore , reliable information on the taxonomy and distribution ranges is still needed for the conservation of the margaritifera species .
we conducted field studies within several regions of eastern russia in the period 2004–2012 ( see fig 1 for the location of the study areas ) . sampling on the russian federation territory was permitted within the framework of the special grants of the russian foundation for basic research ( rfbr , no . 12 - 04 - 00594 ) , the ministry of science and education of russia ( no . № p362 ) , and the scientific program of the ural branch of russian academy of sciences ( no . 12 - p - 5 - 1014 ) . sampling on the protected sites of the kunashir island was permitted by the directorate of the state nature protected area “kurilsky” ( scientific agreement no . 5 / 11 of 17 . 08 / 2010 between the institute of ecological problems of the north of the ural branch of russian academy of sciences and the kurilsky nature reserve ) .
1—kamchatka peninsula ( 2012 , i . bolotov , y . bespalaya , i . vikhrev , m . gofarov ) , 2—central sakhalin ( 2012 , same team ) , 3—southern sakhalin ( 2011–2012 , same team & y . kolosova , o . aksenova ) , 4—kunashir island ( 2011 , same team & y . kolosova , o . aksenova ) , 5—primorye ( 2012 , same team ) , 6—transbaikalia ( 2004–2011 , o . k . klishko ) . data on the studied river sites are presented in s1 – s4 tables .
for molecular analyses , the tissue samples were collected from 52 live bivalves in 15 localities ( see s1 table ) . samples were immediately preserved in 96 % ethanol . dead shells were collected from each field site for morphological investigation ; additional shells from some museum collections were studied ( see s2 – s4 tables ) . a total of 554 shells from 44 localities were studied ( 426 from our collection and 128 museum specimens ) .
the total length of the live specimens and dead shells were measured to the nearest 0 . 1 mm with dial calipers [ 8 ] . the comparative morphologies of the shells were analyzed using shape and structure of the pseudo - cardinal and lateral teeth in the valves , shell shape , umbo position and the patterns of distribution of mantle attachment scars on the inner shell surface . we calculated the plane projection squares of the inner surface of the right valve for the estimation of the density of mantle attachment scars . ten specimens of each species were taken for analysis . the squares were calculated using shape v . 1 . 3 software [ 42 ] . the scars were counted by the gnu image manipulation program ( gimp ) v . 2 . 8 . a normality test of the obtained density values and a one - way anova welsh’s test ( s5 table ) were calculated using statistica v . 10 software .
the soft tissue morphologies were analyzed and compared based on the shape and structure of the inhalant siphon , gills and labial palps . shell and soft tissue photos were taken using a dslr camera ( canon eos 7d , japan ) with a 24–70 mm lens ( sigma af 24–70 mm f / 2 . 8 if ex dg aspherical hsm , japan ) , and photos of the shell structure details and inhalant siphons were taken using a stereomicroscope ( leica m2c , germany ) and a dslr camera with a 100 mm macro lens ( canon macro lens ef 100 mm 1 : 2 , 8 l is usm , japan ) . descriptions of the shell morphologies were based on an analysis of the collected specimens and museum samples using the original species descriptions [ 18 ] , [ 38 ] , [ 43 ] , [ 44 ] , [ 45 ] , [ 46 ] and a few other works [ 23 ] , [ 24 ] , [ 47 ] , [ 48 ] .
we studied the type specimens for the following taxa : unio ( alasmodonta ) dahuricus middendorff , 1850 ; margaritana middendorffi rosén , 1926 ( including specimens of unio ( alasmodonta ) complanatus middendorff , 1851 ) ; and m . sachalinensis zhadin , 1938 ( zisp ) . the type series of several comparatory “taxa” were also investigated , including dahurinaia sujfunensis moskvicheva , 1973 ; d . kurilensis zatravkin & starobogatov , 1984 ; d . tiunovae bogatov & zatravkin , 1988 ; d . komarovi bogatov et al . , 2003 ; d . ussuriensis bogatov et al . , 2003 ; d . prozorovae bogatov et al . , 2003 ; d . transbaicalica klishko , 2008 ; kurilinaia kamchatica bogatov et al . , 2003 ; and k . zatravkini bogatov et al . , 2003 ( zisp ) . in general , the zisp systematic catalog has a very complicated numeration because v . v . bogatov has transferred many specimens from different samples , including true type series , to his newly described comparatory “taxa” .
the mapping was based on the data of our field studies ( see s2 – s4 tables ) . we determined the precise coordinates of investigated river sites using a geographical positioning system ( gps ) . data on other localities were obtained from museum collections and reliable published studies ( see s2 – s4 tables ) . in the cases where a particular map scale did not allow separated precision pointing of closely situated localities , we marked those localities one by one with points and joined them under the one number in the respective table . the arrangement of the localities was digitized and mapped using esri arcgis 10 . the presumed error of determination of the locality coordinates is around ±1–2 km , because published records and collection labels are usually ascribed to an approximate location . the layers of digital maps were added from standard esri data & maps 10 dataset .
) . genomic dna was extracted from the foot or mantle tissues using the diatom dna prep 200 reagents kit ( “laboratoriya isogen” llc , russia ) following the manufacturer’s protocol . the standard forward primer lco 1490 [
] was used to amplify the mitochondrial coi gene from every species . as reverse coi primers , hco 2198 in a modified version ( without the first 6 bases at the 5´ end ) was applied to
) were used to amplify the nuclear 18s rrna gene from every species . the pcr mix contained approximately 200 ng of total cellular dna , 10 pmol of each primer , 200 μmol of each dntp , 2 . 5 μl of pcr buffer ( with 10×2 mmol mgcl
) , 0 . 8 units of taq dna polymerase ( sibenzyme ltd . , novosibirsk , russia ) , and h
o , which was added up to a final volume of 25 μl . thermocycling included one cycle at 95°c ( 4 min ) , followed by 30–35 cycles of 95°c ( 50 sec ) , 52°c ( 50 sec ) , and 72°c ( 50 sec ) and a final extension at 72°c ( 5 min ) . forward and reverse sequencing was performed on an automatic sequencer ( abi prism 3730 , applied biosystems ) using the abi prism bigdye terminator v . 3 . 1 reagent kit . the resulting sequences were checked using a sequence alignment editor ( bioedit version 7 . 2 . 5 , [
the electronic edition of this article conforms to the requirements of the amended international code of zoological nomenclature , and hence the new names contained herein are available under that code from the electronic edition of this article . this published work and the nomenclatural acts it contains have been registered in zoobank , the online registration system for the iczn . the zoobank lsids ( life science identifiers ) can be resolved and the associated information viewed through any standard web browser by appending the lsid to the prefix “ urltoken ” . the lsid for this publication is : urn : lsid : zoobank . org : pub : 46c93315 - 18e0 - 45dd - b121 - 1f225d6e200f . the electronic edition of this work was published in a journal with an issn , and has been archived and is available from the following digital repositories : pubmed central and lockss .
rmbh—russian museum of the biodiversity hotspots of institute of ecological problems of the north of the ural branch of russian academy of science , arkhangelsk , 163000 , russia .
inrec—institute of natural resources , ecology and cryology of the siberian branch of russian academy of sciences , chita , 672000 , russia .
zisp—zoological institute of the russian academy of sciences , st . petersburg , 199034 , russia .
smf—forschungsinstitut und natur - museum senckenberg , senckenberg - anlage 25 , 6000 frankfurt - am - main 1 , germany .
the bayesian analysis of the nuclear 18s rrna gene revealed that the nw pacific species m . middendorffi and m . laevis belong to a well - supported monophyletic clade ( bpp 1 . 00 ) together with the north american species m . marrianae and m . falcata ( fig 2a ) . among these species , m . middendorffi is a sister to m . marrianae ( bpp 1 . 00 ) . m . dahurica , m . auricularia and c . monodonta cluster together in an unresolved clade ( bpp 0 . 79 ) , but there is a sister relationship between the two latter species ( bpp 0 . 99 ) . m . dahurica and m . auricularia both have an intra - specific variation of the nuclear 18s rrna gene with two close haplotypes in each species .
the scale bar indicates the branch length . asterisks : posterior probabilities ≥0 . 95 ; other significant support node values are mentioned in the figure . for detailed locality and specimen data for analyzed haplotypes , see the supplementary materials ( s1 and s2 tables ) . a—the 18s rdna gene dataset . b—the coi gene dataset .
the structure of hinge teeth and the shape and relative dimensions of the shell have specific characteristics that are described in detail below in the taxonomic account of each species . the density of mantle scars has no significant differences ( welch’s test : f = 2 . 45 , df = 16 , 38 , p = 0 . 12 ; ( s5 table ) ) whereas muscle scar has a high variability among studied taxa .
a— margaritifera dahurica ( middendorff , 1850 ) . b— m . laevis ( haas , 1910 ) . c— m . middendorffi ( rosén , 1926 ) . scale bar—1 cm .
a— margaritifera dahurica ( middendorff , 1850 ) . b— m . middendorffi ( rosén , 1926 ) . c— m . laevis ( haas , 1910 ) . scale bar—2 mm .
unio ( alasmodonta ) dahuricus middendorff , 1850 : [ 43 ] : 109 , [ 44 ] : 275–276 , pl . 26 , figs 3–5 .
unio ( margaritana ) dahuricus middendorff , 1850 : [ 58 ] : 699–700 .
unio margaritiferus simpson 1895 , partim ( ident . err . , non linnaeus , 1758 ) : [ 59 ] : 328 .
margaritana dahurica ( middendorff , 1850 ) : [ 23 ] : 109–112 , fig 35 , [ 24 ] : 289 , fig 250 .
margaritifera margaritifera dahurica ( middendorff , 1850 ) : [ 60 ] : 120 , [ 61 ] : 11 .
dahurinaia sujfunensis moskvicheva , 1973 ( comparatory “taxa” ) : [ 62 ] : 1468 , fig 3 , e - h .
dahurinaia sujfunica moskvicheva , 1973 ( inadv . err . in the species description ) . [ 62 ] : 1468 .
dahurinaia tiunovae bogatov & zatravkin , 1988 ( comparatory “taxa” ) : [ 63 ] : 156–158 , fig 1 , a - b .
dahurinaia komarovi bogatov et al . , 2003 ( comparatory “taxa” ) : [ 26 ] : 45–47 , figs 3a & 3d .
dahurinaia ussuriensis bogatov et al . , 2003 ( comparatory “taxa” ) : [ 26 ] : 47 , figs 3b & 3g .
dahurinaia prozorovae bogatov et al . , 2003 ( comparatory “taxa” ) : [ 26 ] : 48 , figs 3c & 3i .
dahurinaia transbaicalica klishko , 2008 ( comparatory “taxa” ) : [ 28 ] : 292–296 , figs 1–4 , 5a .
dahurinaia ( kurilinaia ) laevis klishko , 2009 ( ident . err . , non haas , 1910 ) : [ 64 ] : 237–238 , figs 1–2 .
dahurinaia ( kurilinaia ) zatravkini klishko , 2009 ( ident . err . , non bogatov et al . , 2003 ) : [ 64 ] : 238–239 , fig 3 .
margaritifera dahurica inoue et al . , 2013 ( inadv . err . ) : [ 65 ] : fig 3 ( a ) .
a—lectotype ( zisp : no . 7a ) . b—specimen from komarovka river , razdolnaya river basin , primorye . photos by i . v . vikhrev . scale bar—2 cm .
a— margaritifera dahurica ( middendorff , 1850 ) . b— m . middendorffi ( rosén , 1926 ) . c— m . laevis ( haas , 1910 ) . scale bar—1 cm .
microphotographs of the mantle attachment scars on shells of four eastern asian margaritiferid species .
a— margaritifera dahurica ( middendorff , 1850 ) . b— m . middendorffi ( rosén , 1926 ) . c— m . laevis ( haas , 1910 ) .
green circles are representing recent viable populations ( observed since 2000 ) , white circles—old records ( until 2000 ) . question mark is indicated an uncertain record from the langry river [ 69 ] , [ 26 ] . grey areas are indicated an approximate modern species range ( it is shown only for the large river systems ) . species locality numbers on the map correspond to numbers in s2 table .
a— margaritifera dahurica ( middendorff , 1850 ) : the ilystaya river , primorsky kray . b— m . middendorffi ( rosén , 1926 ) : the nachilova river , kamchatka . c— m . middendorffi ( rosén , 1926 ) & m . laevis ( haas , 1910 ) : the golovnina river , kunashir island . photos by y . v . bespalaya , y . s . kolosova & i . v . vikhrev .
“transbaikalien” [ 43 ] : 109 ; “am zusammenflusse des argunj mit der schilka” [ 44 ] : 276 ( confluence of the rivers argun and shilka , the upper amur basin : see fig 8 & s2 table , locality no . 36 ) .
the middendorff’s type series includes two specimens that are deposited in the zisp collection . bogatov et al . [ 26 ] : 45 designate specimen no . 7a as a lectotype , because it was pictured by middendorff [ 44 ] : pl . 26 , figs 3 – 5 ; and assigned the second specimen no . 7b ( single valve ) as a paralectotype . the lectotype shell has 105 mm length , 32 mm height and 25 mm width . it is noteworthy , that bogatov et al . [ 26 ] were not using the protologue of middendorff [ 43 ] for their revision , and cited only middendorff’s later work [ 44 ] .
the amur basin ( within the territories of russia , mongolia and china ) , the razdolnaya basin ( upper tributaries ) , the peschernaya ( kulumbe ) river , the iska river and the arey lake ( fig 8 & s2 table ) .
different types of watercourses , such as small streams , small and medium sized rivers , as well as large rivers ( rivers ussuri , arkhara , shilka , etc . ) ( fig 9a ) . the sole lake population was found in arey lake , transbaikalia , siberia , russia [ 28 ] ; but divers recorded only a few dead shells here in the year 2013 ( o . k . klishko , pers . comm . ) . populations prefer sand - gravel and gravel - pebble grounds at the riffles and runs . sometimes , individual specimens were observed on the clay and silt - sand bottom of the pool river sites .
not known . actually , a list of seven salmonid species , which can serve as hosts of the m . dahurica [ 36 ] , has not been verified experimentally .
all of the referred comparatory “taxa” of the genus dahurinaia were synonymized with m . dahurica based on shell morphology [ 4 ] , [ 8 ] , [ 31 ] , [ 39 ] . our molecular data confirmed this decision . for example , bogatov [ 29 ] noted that the single known dahurinaia sujfunensis population inhabits razdolnaya basin , which is separate from the amur drainage . bogatov reports that “…between the amur basin and basins of rivers of the south of primorsky kray , no common species of large bivalves has been found yet , which is explained by the historic development of these basins” [ 29 ] : 674 . however , according to new molecular and morphological data , the specimens from the razdolnaya drainage are identical to typical m . dahurica specimens from different parts of the river amur basin .
unio ( alasmodonta ) complanatus middendorff , 1851 ( ident . err . , non dillwyn , 1817 ) : [ 44 ] : 273–274 , pl . 27 , figs 1–6 .
margaritana middendorffi rosén , 1926 : [ 46 ] : 269–270 , [ 23 ] : 112–114 , fig 36 , [ 24 ] : 289 , fig 251 .
dauhrinaia middendorffii buyanovsky , 1993 ( inadv . err . ) : [ 67 ] : 29 .
kurilinaia kamchatica bogatov et al . , 2003 ( comparatory “taxa” ) : [ 26 ] : 48 , figs 4a & 4c .
kurilinaia zatravkini bogatov et al . , 2003 , partim ( comparatory “taxa” ) : [ 26 ] : 49–50 , figs 4b & 4f .
margaritifera laevis huff et al . , 2004 ( ident . err . , non haas , 1910 ) : [ 38 ] : 381 , genbank acc . no . ay579124 .
a—holotype of m . togakushiensis [ 18 ] : 137 , figs 5 – 8 . b—lectotype of m . middendorffi ( zisp : no . 6 ) . photo by i . v . vikhrev . scale bar—2 cm .
circles— m . middendorffi locations , squares— m . togakushiensis locations . green circles and squares are representing recent viable populations ( observed since 2000 ) , white circles—old records ( until 2001 ) , yellow squares—records without exact dates . grey areas indicate approximate modern species ranges ( showing only the large river systems ) . species locality numbers on the map correspond to numbers in s3 table .
“reka golyshka” [ the river golygina , kamchatka peninsula : see fig 11 & s3 table , locality no . 1 ] [ 46 ] : 269 ; “kamtschatka ; im see mjäkéshino des südendes ( lopatka ) dieser halbinsel” ( kamchatka ; the lake mekeshino on the southernmost extremity of the peninsula : see fig 11 & s3 table , locality no . 4 ) [ 44 ] : 274 .
rivers of the kamchatka peninsula , kurile archipelago , sakhalin island ( fig 11 & s3 table ) , and likely of japan .
small streams , small - and medium - sized rivers ( fig 9b ) . usually , populations were recorded on sand - gravel grounds of the runs but , in the extreme north of the range , the species inhabited only pool river sites . in some rivers of the sakhalin and kunashir islands , far east of russia , the species coexists with m . laevis ( see fig 9b & s3 table ) .
not known . kondo & kobayashi [ 18 ] stated salvelinus leucomaenis as a host fish for m . togakushiensis . as far as we suppose m . togakushiensis and m . middendorffi conspecific , they may have the same host fish . [ 18 ] .
then , simpson [ 59 ] : 328 noted that middendorf’s specimens are “…without lateral teeth , and appear to be a stunted form of unio margaritiferus ” . finally , rosén [ 46 ] described m . middendorffi as a separate species and not as an intra - specific form of m . margaritifera . however , haas [ 61 ] , [ 60 ] incorrectly cited rosén’s name as margaritana margaritifera middendorffi . kurilinaia kamchatica bogatov et al . , 2003 is a comparatory “species” that was recently synonymized with m . middendorffi [ 31 ] . kurilinaia zatravkini bogatov et al . , 2003 is also a comparatory “species” ; its holotype belongs to m . laevis , but among the paratypes , we found four specimens of m . middendorffi ( zisp : nos . 5 , 5a , 7 and 8 ) . records of margaritifera specimens on kunashir island [ 68 ] : 134 can pertain to m . middendorffi as well as to m . laevis . therefore , some published references [ 8 ] , [ 67 ] , [ 69 ] , [ 70 ] with records from the sakhalin and southern kurile islands cannot be used without revision of the specimen samples .
margaritana dahurica kobelt , 1879 ( ident . err . , non middendorff , 1850 ) : [ 71 ] : 427–428 , pl . 13 , figs 1–2 .
unio margaritifer schrenck , 1867 , partim ( ident . err . , non linnaeus , 1758 ) : [ 58 ] : 700–704 .
unio margaritiferus simpson , 1895 , partim ( ident . err . , non linnaeus , 1758 ) : [ 59 ] : 303 .
margaritana sachalinensis zhadin , 1938 : [ 23 ] : 114–115 , fig 37 , [ 24 ] : 289–291 , fig 252 .
margaritifera margaritifera laevis ( haas , 1910 ) : [ 60 ] : 120 , [ 61 ] : 12 .
dahurinaia kurilensis zatravkin & starobogatov , 1984 ( comparatory “taxa” ) : [ 72 ] : 1789–1790 , figs 11–14 , [ 66 ] : 21 .
dahurinaia shigini zatravkin & bogatov , 1987 : ( comparatory “taxa” ) : [ 66 ] : 23–24 , fig 4b .
margaritifera ( dahurinaia ) kunahiriensis habe , 1991 ( inadv . err . ) : [ 73 ] : 3 .
dauhrinaia kurilensis buyanovsky , 1993 ( inadv . err . ) : [ 67 ] : 29 .
margaritana sacchariensis bába , 2000 ( inadv . err . ) : [ 74 ] : 133 .
kurilinaia kurilensis ( zatravkin & starobogatov ) : [ 26 ] : 42 , [ 27 ] : 25 .
kurilinaia zatravkini bogatov et al . , 2003 : partim ( comparatory “taxa” ) : [ 26 ] : 49–50 , figs 4b & 4f .
a—sennaya river , kunashir island . b—tym’ river , sakhalin island . photos by i . v . vikhrev . scale bar—2 cm .
green circles are representing recent viable populations ( observed since 2000 ) , white circles—old records ( until 2001 ) , yellow circles—records without exact dates . grey areas indicate the approximate modern species range ( showing only the large river systems ) . species locality numbers on the map correspond to numbers in s4 table .
type specimen ( holotype ) of haas [ 45 ] is deposited in the senckenberg museum , frankfurt ( no . smf3626 ) [ 39 ] .
sakhalin island , south kurile islands ( kunashir , iturup and shikotan ) , honshu and hokkaido islands ( fig 13 ) . correspondence on the species occurrence in the upper amur basin , transbaikalia [ 64 ] is based on an erroneous identification ; however , all of these specimens belong to m . dahurica based on morphological and molecular data ( see s1 table ) .
small streams , small - and medium - sized rivers . usually , populations were recorded on sand - gravel grounds at the run and pool sites . in several rivers of sakhalin , kunashir , honshu and hokkaido islands , islands , the species coexists with m . middendorffi ( see fig 9c & s4 table ) .
the masu salmon ( oncorhynchus masu ( brevoort , 1856 ) ) [ 18 ] .
in the main , species synonymy was provided in previous reviews [ 4 ] , [ 18 ] , [ 31 ] , [ 39 ] . m . perdahurica ( yokoyama , 1932 ) , m . otatumei ( suzuki , 1942 ) and m . owadaensis ( noda , 1970 ) , three fossil cenozoic margaritiferid species from japan , were also assumed as m . laevis representatives [ 39 ] . however , the condition of specimens of these species is very poor [ 75 ] , [ 76 ] , [ 77 ] , [ 78 ] . it is impossible to reliably compare these fossils with shells of recent margaritiferids . moreover , most of the known fossil specimens , including m . perdahurica and m . otatumei , are ancient and belong to the eocene or oligocene by stratigraphic classification [ 78 ] , [ 79 ] . it is unlikely that these fossils belong to recent species , but thorough revision of all specimens and collections of fossil margaritiferids would be necessary , in order to clarify the relationships of these bivalves [ 80 ] .
three margaritifera species inhabit the rivers of the russian far east , as discerned from morphological and molecular data : m . dahurica ( middendorff , 1850 ) , m . middendorffi ( rosén , 1926 ) and m . laevis ( haas , 1910 ) . however , the rivers of northeastern russia , where large mainland regions remain unexplored , are still not completely studied ; therefore the same species that were previously noted by smith [ 4 ] or additional species , may inhabit the north of the khabarovsky kray , the magadan oblast , and the koryakia and chukotka districts . these areas are difficult to access and require future studies .
m . dahurica has the largest range among the eastern asian species in the genus ( see fig 8 ) . this species is found in almost all of the major tributaries of amur basin , an area of approximately two million km 2 , as well as in razdolnaya basin and in two separate small rivers . a similar distribution pattern was found in some freshwater fish species , among which approximately 16 were endemic to this area [ 81 ] . we found only a single old record of m . dahurica from sungari river , the largest chinese tributary of the amur , and a few occurrences from mongolia . however , this species is likely widely distributed in part of the amur river system within the territory of those countries . dashi - dorgi [ 82 ] reported m . dahurica as one of the most common mussel species in the rivers of eastern mongolia . this species is not found in the rivers of the kurile islands and the most of sakhalin island . bogatov [ 69 ] and bogatov et al . [ 26 ] reported a few specimens from the langry river , which is situated on the extreme northwest of the sakhalin island . it is possible that because this river empties into the amur estuary , this river might have belonged to the ancient system of the paleo - amur [ 81 ] . the range of some amurean fish species also includes rivers in northwestern sakhalin island [ 83 ] . nevertheless , the species identification is in need of revision .
from our data , the range of m . laevis is significantly narrower than the distribution of the previous species ( see fig 13 ) . this species has a more southerly distribution , and has not been found north of central sakhalin . however , the host fish oncorhynchus masu is much more widespread northward up to kamchatka peninsula . most of the known localities of m . laevis are situated on the honshu island , and their number is linearly reduced to the north . a few fish species have a distribution resembling this , including the sakhalin taimen ( hucho perryi ( brevoort , 1856 ) ) [ 83 ] .
in this study , we analyzed the applicability of specific shell features that were indicated in previous studies for reliable species identification . three pearl mussel species were identified using a complex of morphology patterns and molecular data . the development and expression of hinge teeth , the shape and the relative dimensions of the shell , the mantle attachment scars , and the muscle scar shape are the most used conchological key features [ 4 ] , [ 10 ] , [ 18 ] , [ 23 ] , [ 24 ] , [ 34 ] , [ 38 ] , [ 47 ] , [ 43 ] , [ 44 ] , [ 45 ] , [ 46 ] , [ 95 ] , [ 96 ] , [ 97 ] , [ 98 ] , [ 99 ] .
s1 table . list of sequenced margaritifera specimens including species , localities and voucher details as well as ncbi genbank accession numbers .
s2 table . list of known localities of margaritifera dahurica ( middendorff , 1850 ) .
s3 table . list of known localities of margaritifera middendorffi ( rosén , 1926 ) and margaritifera togakushiensis ( kondo and kobayashi , 2005 ) .
s4 table . list of known localities of margaritifera laevis ( haas , 1910 ) .
s5 table . variance and significance tests results for mantle attachment scars density within three margaritiferid species .
s6 table . additional species sequences that were used in the analyses with ncbi genbank accession numbers .
we are thankful to to dr . p . v . kijashko and l . l . jarochnovich ( zoological institute of russian academy of sciences , st . petersburg , russia ) for assistance in studies of margaritifera specimens in zisp collection . the authors express their gratitude to mr . e . p . dekin ( russia ) , mr . m . a . antipin ( state nature protected area “kurilsky” , russia ) . special thanks go to mr . o . n . bespaliy ( russia ) for his excellent fieldwork assistance .
conceived and designed the experiments : inb yvb ivv . performed the experiments : inb yvb ivv ova myg okk ysk avk isp esk st nib isv . analyzed the data : inb yvb ivv avk . contributed reagents / materials / analysis tools : yvb ivv ova pea myg okk ysk avk aal isp esk st nib isv . wrote the paper : inb yvb ivv avk .
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