rosdhu queen ( foaled 10 february 2010 ) is an irish-bred , british-trained thoroughbred racehorse and broodmare .

in a racing career which lasted from july 2012 until august 2013 she won four of her eight races .

as a two-year-old in 2012 she was one of the best filly 's of her generation in britain , winning all four of her races including the st hugh 's stakes , lowther stakes and cheveley park stakes .

she failed to win in 2013 but finished fourth in the fred darling stakes and produced arguably her best effort when finishing fifth in the diamond jubilee stakes .

at the end of her racing career she was sold to become a broodmare for the coolmore stud .

rosdhu queen

thoroughbreds such as rosdhu queen ( left ) were previously purchased at the craven breeze up sale .
johnny murtagh riding rosdhu queen ( 2l , grey ) win the jaguar cars cheveley park . . .
rosdhu queen had the aura of a topflight filly in the making when haggas paraded last season’s revelation .
rosdhu queen can capitalise on the return to competing against her own sex by landing this afternoon’s 32red summer stakes at york .
william haggas with his 1 , 000 guineas hope rosdhu queen at his newmarket stables on wednesday morning . photograph : alan crowhurst / getty images
past gems to have been purchased in previous years include cheveley park stakes winner rosdhu queen and next month ' s epsom derby hope great white eagle .
johnny murtagh riding rosdhu queen ( 2l , grey ) win the jaguar cars cheveley park stakes at newmarket racecourse on september 29 , 2012 in newmarket , england .
“he’s really enjoying himself now and the queen is delighted he is doing so well , ” said sir michael oswald , who manages the queen’s national hunt interests .
rosdhu queen has both attributes , speed through invincible spirit and stamina through green minstrel and green tune and this is usually a good combination to have in this forth coming race in may .
the gist of which is that if rosdhu queen can become even half as influential a broodmare as sookera turned out to have been , then her new owners will have bought very well indeed .
four winners in the past decade started out over five furlongs , though only the very speedy attraction won , so it ' s not impossible for rosdhu queen to step up in trip and claim this .
the coolmore team had also struck earlier to secure the group 1 cheveley park stakes winner rosdhu queen for 2 . 1m guineas through agent stephen hillen despite spirited efforts from john warren and barouche stud’s rory matthews .
her penultimate race saw her competing at the highest grade : the jaguar cheveley park stakes group 1 at newmarket . here she would attempt 6f for the first time . finishing 7th behind rosdhu queen was no disgrace .
olivier peslier , jockey of the two - length second queen catrine , said : “firm . ”
the 11 - year - old gelding was the last horse bred by the queen mother and , trained by nicky henderson for the queen , won eight races over fences and £143 , 000 .
today’s newspapers concentrate on the king george vi & queen elizabeth stakes ( sponsored by betfair ) .
rosdhu queen may well have run by the time you read this . she ' s entered in newbury ' s fred darling stakes , a race which was last won en route to guineas glory by wince in 1999 .
there must be doubts about the ability of unbeaten rosdhu queen to get 7f and maureen ( 2 . 55 ) gets the nod in the fred darling . the filly wasn’t at her best in the cheveley park last time , but had looked very good in the princess margaret at ascot previously and deserves another chance . she is currently 33s for the 1000 guineas at betvictor with rosdhu queen 20s for the first fillies’ classic of the season .
next week his oaks prospect lady nouf steps out in the nell gywn at the craven meeting and leading 1 , 000 guineas hope and last season’s cheveley park winner rosdhu queen reappears in the fred darkling at newbury next saturday .
the queen’s barber shop starred in the retraining of racehorses parade in the paddock at ascot before racing .
the cheveley park winner , rosdhu queen , has fallen just short of top class this season , fourth in the fred darling and fifth in the diamond jubilee , and is a stand - out here , if it wasn’t for her temperament .
the trainer jokes about getting to the sunday after rosdhu queen ' s trial and thinking ,
oh god , this is going to be a long year
. but an alternative prediction , offered elsewhere in the conversation , sounded more sincere .
i am invincible is by group 1 winning sprinter and champion european sire invincible spirit , the sire of more than 60 stakes - winners including group 1 winners moonlight cloud , yosei , hooray , fleeting spirit , mayson , rosdhu queen and lawman .
in a nutshell , then , i ' m looking towards the top of the market with regards to unraced fillies this year . that brings in just the judge , big break , and rosdhu queen ( likely runner in fred darling on saturday ) .
with johnny murtagh being given first refusal for the ride on rosdhu queen , who won under four different jockeys when maintaining her unbeaten run last season , haggas added : “she’s very straightforward and she thinks she’s good , which is half the battle . i’d never write her off . ”
another godolphin - owned two - year - old certify , trained by mahmood al zarooni , also enjoyed an unblemished juvenile career and the four - time winner is the cartier two - year - old filly , getting the nod over sky lantern , rosdhu queen , flotilla and silasol .
rosdhu queen ( ire ) b . m , 2010 { 9 - f } dp = 5 - 3 - 9 - 1 - 0 ( 18 ) di = 2 . 27 cd = 0 . 67 - 8 starts , 4 wins , 0 places , 0 shows career earnings : £189 , 986
haggas ' s other great challenge is to get rosdhu queen , who has never raced beyond six furlongs and , in his words ,
looks like a sprinter
, to stay a mile . it is the betting market ' s doubts on that score that have led bookmakers to offer 20 - 1 for the guineas .
. rosdhu queen ' s main problem may be stamina . quick enough to win a five furlong maiden on debut - and a six furlong group 1 on her last juvenile start - she ' ll have another 33 % to race here , and while her breeding gives cause for optimism , the form book is keeping mum .
the despondency of her connections was in poignant contrast to the delight of william haggas , a proud yorkshireman exiled in newmarket , whose rosdhu queen filled the sad vacuum to extend her unbeaten record to three . always in the van , she was pressed by baileys jubilee inside the last but found extra to score by just under two lengths .
i can’t back rossdhu queen after seeing her play up in the stalls at newbury and ascot . one of these days , she’ll boil over completely .
gold value bet : 5 . 7pts win body and soul and 2 . 2pts win ( stakes saver ) rossdhu queen ( 2 . 25 york )
the excitement of royal ascot ' s second day sees the queen mary stakes group 2 ( 19th june , 2013 ) . this 5f race for two - year - old fillies is named after queen mary the consort of king george v . the race was first run in 1921 with wild mint proving victorious .
old - timer nanton rolled back the years to record what was a popular win in the queen mother’s cup and returns for the groceryaid chairman’s charity cup handicap .
by invincible spirit ( 1997 ) sprint cup ( g1 ) , etc . sire of 1 , 662 foals aged three and up , including territories , charm spirit , fleeting spirit , hooray , kingman , lawman , mayson , moonlight cloud , national defense , profitable , rosdhu queen , shalaa , signs of blessing , vale of york , yosei , zebedee , etc .
' every day you are looking to unearth a gem , a queen ' s logic or a youmzain . that ' s the buzz – the competing . and i…
last years cheveley park stakes winner rosdhu queen has a very encouraging pedigree to step up and run well in this race . she is by invincible spirit a smart sprinter at two , he never made a positive transition to three when only encountering two runs which resulted in two non place runs in listed and group 2 spheres , he went on to achieve better success at four and five .
the local ascot news is another fan . looking forward to “a thrilling renewal of the king george vi & queen elizabeth stakes” , the paper’s racing expert tips cirrus des aigles .
rosdhu queen won her second race at newbury only last friday .
i don ' t normally run them back this quick ,
haggas said .
but steve parkin , who owns her , is a yorkshireman as well – so what did we have to lose ? we may as well have some fun , it ' s what we do it for . and she ' s pretty good .
rosdhu queen won the group 2 lowther stakes before going on to take the group 1 cheveley park stakes for trainer william haggas who also trained yesterday’s 4m guineas session topper dancing rain . she is also a graduate of the tattersalls craven breeze up sale - having been bought by david redvers bloodstock in april 2012 from grove stud for 65 , 000gns for steve parkin , owner of the filly through his company clipper logistics .
rosdhu queen will be offered to johnny murtagh ,
haggas said on wednesday .
but she ' ll run in a trial and , if he ' s got a better opportunity , he ' ll probably do that . i ' ve never done any good in the 1 , 000 guineas but i haven ' t really tried very hard . we don ' t get warm until the weather gets warm .
time : new course record 2m 24 . 60s ( smashed previous record held by harbinger when he won the king george vi & queen elizabeth stakes in 2010 of 2m 26 . 78s )
william haggas and johnny murtagh , who teamed up to pinch the oaks in 2011 with the 20 - 1 shot dancing rain , may come together once more in pursuit of classic glory when rosdhu queen lines up for the 1 , 000 guineas here next month . the filly , unbeaten in four races last year , has had four different jockeys so far but her trainer is clear about which one he hopes to have aboard on 5 may .
one of newmarket’s two - year - old heroines of 2012 was on show on wednesday morning ahead of her intended assault on the 200th running of the 1 , 000 guineas on may 5 . william haggas paraded the cheveley park stakes winner rosdhu queen at his somerville lodge stables and indicated that she will be seen first in the fred darling stakes at newbury , in which she will not have to carry a penalty for her group 1 success .
novellist today became the second german - trained winner of the king george vi & queen elizabeth stakes ( sponsored by betfair ) , scoring by five lengths in course record timne of 2m 24 . 60s .
trainer charlie hills is hoping that queen catrine will land a big prize this year after the filly finished two - lengths second to princess noor in the six - furlong group three princess margaret juddmonte stakes .
at 6 . 2 , body and soul is excellent value and a sub - 110 % betdaq market allows me to have a saver on rossdhu queen in case she is settled and throws egg on my face .
elusive kate came into this fresh last year and was just beaten by giofra on soft ground not to her liking . she’s had a run back this time ( some ‘run’ ! fourth in the queen anne ) .
rosdhu queen will start her season in newbury ' s fred darling a week on saturday , while haggas has another 1 , 000 guineas candidate in lady nouf , who will turn out for the nell gwyn next wednesday when racing resumes at the trainer ' s local track after an absence of six months . of lady nouf he says :
her work has been good and i can ' t yet get her off the bridle . not that i ' ve tried very hard .
varian also runs ektihaam in the feature race , the betfair - sponsored king george vi & queen elizabeth stakes , and said : “i hope that we haven’t peaked too soon – it’s a nice way to start the day . ”
2 . 10 newmarket ( duchess of cambridge stakes ) six winners of this had been first or second at royal ascot , and the question is whether rizeena can carry a group - 2 penalty – from her scintillating queen mary win – over this extra furlong .
from the irish contingent to have run this term , snow queen leads the charge at around 33 / 1 for those with an entry . she was third , as mentioned , in the 1000 guineas trial at leopardstown , and previously raced seven times as a juvenile .
in both cases , and in the case of snow queen , they ' d raced in group 1 company as a junior . again , as mentioned , i feel that for the more experienced runners , a crack at top class is a significant pointer to perceived ability .
there was a second successive german - trained winner of the group one king george vi & queen elizabeth stakes ( sponsored by betfair ) when the andreas wohler - trainer novellist set a new course record of 2 minutes 24 . 6 seconds in the mile and a half showpiece .
immortal verse set a european record for a broodmare when selling for 4 . 7m guineas on a day of extraordinary trade at the tattersalls december mare sale . additionally , rosdhu queen and dream peace sold for 2 . 1m guineas and 2 . 7m guineas respectively , pushing the turnover past 30 , 000 , 000 guineas for only the second time in european auction history . in total , 190 lots were sold for 34 , 478 , 500 guineas , at an average of 181 , 466 guineas and at median of 76 , 500 guineas resulting in rises of 45 % for turnover , 40 % for average and 16 % for median .
he was better than ever during 2012 and brilliant victories included the devastating 11 - length win in the group one queen anne stakes at royal ascot in june and his imperious success when tried over 10 furlongs for the first time in the group one juddmonte international at york in august .
only just the judge comes out of the sky lantern double as top class alongside her . the queen anne second and fourth have won only group 3s and , with the exception of just the judge , the guineas also rans have nothing to show since but one listed win ( winning express ) .
this is far from uncommon for a ballydoyle youngster , with last year ' s 1000 heroine , homecoming queen , having had eleven starts as a two year old , and two as a three year old ! moreover , o ' brien ' s 2011 runner up , together , had had eight juvie runs .
what i can say is that only last year ' s winner , homecoming queen , had more than one run . she was a bit of a fluke winner after a long delay at the start , and she failed to make the frame thereafter in two subsequent starts , despite being sent off favourite both times .
the winner this year , rawaaq , is not entered at newmarket and is far more likely to run in the irish 1000 guineas . the second placed horse is also not entered , but the third , snow queen , may make the trip for o ' brien . she ' s currently a best priced 33 / 1 .
eagerly awaited , last year’s g1 cheveley park s . winner rosdhu queen ( ire ) ( invincible spirit { ire } ) from william haggas’s draft was the subject of a predictably heated bidding war after opening up at 500 , 000gns . seeing off first rory matthews of barouche stud and then john warren , stephen hillen prevailed at 2 . 1million . “she’s been bought for coolmore , ” hillen said . “i should imagine she is going to be one for galileo . she is a beautiful filly , a great physical . she is by invincible spirit who is doing so well , she is a group 1 - winning sprinter and won her group 1 as a two - year - old – you don’t get many of those coming onto the market . ”
in ireland , it ' s all about the 1000 guineas trial run at leopardstown . last year , homecoming queen won that for aidan o ' brien before her shocking 25 / 1 victory at newmarket . in 2005 , the same trainer ' s virginia waters scored in both races , paying out at 12 / 1 for her streak across the heath .
barry orr , uk and ireland pr manager for sponsors betfair , commented before racing : “we are going six places in the third race , the cash out multiples only on betfair international handicap and we feel that the favourite , cirrus des aigles , in the king george & queen elizabeth stakes ( sponsored by betfair ) , is very opposable . all the bookmakers will want to lay against him . ”
her next target was the queen mary stakes group 2 at royal ascot , 2012 . although priced at 20 / 1 , seemingly second string to the stable ' s debut winner upward spiral , she made the most of her experience winning by a length from michael bell ' s hoyam who finished with great gusto . once again , ceiling kitty defied the odds beating twenty six rivals bagging a prize of over £42 , 000 .
snow queen missed the break by at least ten lengths that day , used up a lot of energy to tag herself onto the pack , and then probably hated the good ground as well . her chance looks to rest on there being plenty of rain in newmarket between now and may 5th . that said , the balance of her form looks more limited than many of these , as well , as an official rating of just 99 implies .
tom queally riding frankel in a racecourse gallop before racing at newmarket racecourse on september 29 , 2012 in newmarket , england .
tom queally riding frankel in a racecourse gallop before racing at newmarket . . .
gerald mosse riding siyouma ( l ) win the kingdom of bahrain sun chariot stakes at newmarket racecourse on september 29 , 2012 in newmarket , england .
gerald mosse riding siyouma ( l ) win the kingdom of bahrain sun chariot stakes at . . .
gerald mosse riding siyouma ( c ) win the kingdom of bahrain sun chariot stakes at newmarket racecourse on september 29 , 2012 in newmarket , england .
gerald mosse riding siyouma ( c ) win the kingdom of bahrain sun chariot stakes at . . .
sir henry cecil with teddy grimthorpe at newmarket racecourse on september 29 , 2012 in newmarket , england .
sir henry cecil with teddy grimthorpe at newmarket racecourse on september 29 , 2012 . . .
sir henry cecil with frankel at newmarket racecourse on september 29 , 2012 in newmarket , england .
sir henry cecil with frankel at newmarket racecourse on september 29 , 2012 in . . .
william buick riding bronze angel ( 3rd l , yellow cap ) win the betfred cambridgeshire at newmarket racecourse on september 29 , 2012 in newmarket , england .
william buick riding bronze angel ( 3rd l , yellow cap ) win the betfred . . .
after the sun king , the deluge . those privileged to be here for the first day of the meeting will attest that the knavesmire has rarely , if ever , taken the imprint of a greater thoroughbred than frankel . yesterday , however , they experienced an obverse of the sport ' s glories . both big races were run in a downpour , while darker clouds still extinguished the dazzling promise of newfangled .
runaway winner of her two previous starts , newfangled started a hot favourite for the jaguar cars lowther stakes . barely a furlong after leaving the gate , however , her career could be presumed over . alarmed by a sudden loss of rhythm , william buick desperately sought to arrest her momentum . the stricken filly , initially treated behind screens , was taken away for scans but the initial diagnosis was of a pelvic fracture .
so scrupulous in the placement of his horses , haggas admitted this an unexpected gift on his 52nd birthday .
that wasn ' t the plan ,
he said .
we were going to ride her for third and hope we got lucky .
sure enough , he has given her an entry against older sprinters in the prix de l ' abbaye at longchamp on arc day , though the flying childers stakes at doncaster next month beckons first . richard hughes , her jockey , was profiting doubly from the misfortunes of others , having picked up the mount only after ryan moore suffered injury at warwick on tuesday .
it ' s funny how things work out ,
he said .
ryan should have ridden her , but broke his wrist on a horse i ' d have been riding if i hadn ' t picked up a ban .
with moore now sidelined for several weeks , hughes is long odds - on to win a first title . in the trainers ' championship , meanwhile , john gosden retains every chance of a parallel distinction , no less his due , but this was a rare black day in his season . after the cruel mishap to newfangled , he saddled the fugue as favourite for the darley yorkshire oaks – only to see her run out of it close home by the rallying shareta .
in a race run at a diffident gallop , into the teeth of a squall , buick sent the fugue past was inside the final furlong . but this had turned into a very different test from the one that served the fugue so well at goodwood last time , and the french filly wore her down by a neck . a fine ride , this , from christophe lemaire , who shadowed the steady pace but kept his cool once the tempo quickened . shareta was a surprise runner - up in the arc last year , but alain de royer - dupré ' s priority for now will be the prix vermeille .
gosden felt the ground had turned against the fugue , who will duly be pointed towards the breeders ' cup . sadly , there is little evidence that connections of frankel will heed a groundswell of interest in their champion venturing to either california or longchamp , with ascot in october remaining favoured as the bird in the hand . lord grimthorpe , racing manager to khaled abdulla , summed up the mood in the camp yesterday by saying :
the best time to leave a party is when you least want to go .
the big race today is the coolmore nunthorpe stakes , in which nocturnal affair ( 3 . 40 ) looks value at 25 - 1 . it is only a year since the south african import made his debut for david marnane , and he has quickly progressed to rub shoulders with some of the quickest on the planet in dubai . true , ortensia swept past him on world cup night and returned to her best at goodwood last time , but she pounced off a strong pace on both occasions and this track may not play to her strengths . nocturnal affair shaped very nicely in a recent warm - up at tipperary , tanking along until flattening out in soft ground . the fellow on top brings a momentum all of his own . ridden in dubai by moore , the gelding is partnered for the first time by hughes .
bordoni ( 7 . 05 hamilton ) shared his stable ' s loss of form but can contribute to revival off mark 4lb lower than on his handicap debut back in april .
escape to glory ( 5 . 15 newmarket ) back into lower grade , where he has touch of class .
camborne is 7 - 1 from 9 - 1 with william hill for the betfred ebor handicap at york tomorrow .
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winx ' s staying power as one of the world ' s top rac . . .
t . j . comerford , assistant trainer for aidan o ' brie . . .
that prospect seemed a long way off as the 52 - year - old trainer watched a handful of horses coming up the al bahathri gallops in freezing temperatures . deep frosts and biting winds have , he reports , been the main feature of newmarket weather this year and it has made his task
challenging
, though he hopes that other stables around britain have been in a similar position .
realistically she possibly won a weak cheveley park and she ' s done nothing really to set anyone ' s pulses racing but us . but she is a cheveley park winner . the only thing i will say is that in the lowther i didn ' t think she ' d stay and , when they came to her , she went again . i think she ' s quite difficult to pass . the one thing you can ' t buy is this bit ,
he said , patting the area of his chest that covers his heart ,
and she ' s obviously got plenty of that . she thinks she ' s good . i ' d never write her off .
haggas has hopes of three other runners being aimed at wednesday ' s card here , including the unraced battalion , supplemented into the derby this week .
whether he ' s quite up to that , i don ' t know , but he ' s been working well .
we ' ve got a very strong stable now . it ' s taken 25 years to build it up . the only real concern i have is health . if we keep them healthy , we ' ll have a nice year because we ' ve got the stock . but if you don ' t get the health right , it can go very pear - shaped . all sorts of things can happen . one batch of hay can knock you out for a month . ringworm . you don ' t think about it but you ' re conscious of it the whole time .
day one of newmarket ' s craven meeting next week will have an added attraction as charlie hills plans to give the 1 , 000 guineas favourite , just the judge , a gallop up the rowley mile before racing begins .
meanwhile , newmarket officials announced an extra £800 , 000 from jockey club funds for prize money at the track this year , taking the july cup to £500 , 000 and making it the joint most valuable group one sprint in europe .
meanwhile the leading derby hope telescope could make his his first appearance of the season at sandown on friday week . the owners highclere tweeted :
telescope worked very well this morning . could reappear in a mile conditions race at sandown .
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the 2013 diamond jubilee stakes marks the final of nine group 1 races in the annual royal ascot meeting , and a former winner in society rock is the current favorite from the no . 8 post position .
society rock enters having won his most recent race at the duke of york stakes , but he will have to negotiate the massive field of 17 other horses to find the winner ' s circle on saturday at ascot racecourse .
there are only six furlongs for jockey kieren fallon to make that happen . even a jockey of his immense experience will have a difficult time maneuvering that well against what should be a viable bunch of fellow competitors .
let ' s take a look at the post time and odds for each horse as the race approaches , then get into some predictions , followed finally by complete projections for all horses .
note : background information and prior royal ascot races were obtained from ascot ' s official website . history of horses is courtesy of horse racing nation .
when : saturday , june 22 ; post time is 10 : 45 a . m . et
horses , jockeys and post positions are courtesy of racingpost . com . odds were obtained from william hill and are current as of 3 : 30 p . m . et on 6 / 21 / 2013 .
the 2011 winner of this race is now six years old but apparently isn ' t showing signs of slowing down in light of the aforementioned win at the group 2 duke of york stakes .
an even more impressive victory preceded that in the group 1 sprint cup in september 2012 . fallon got the mount on that occasion as well .
however , the combination of the size of the field , short distance and potential traffic issues threaten to thwart society rock ' s bid to win this race for a second time . if the horse did pull out the victory , it would be just the second time in 50 years such a feat has been accomplished , per urltoken ' s myra lewyn .
history is already against society rock , but the weather might be , too . bbc notes the possibility of heavy showers after some morning rain on saturday . that will cause the horses to sink deeper into the turf track , and thus make the six - furlong sprint even more grueling .
society rock isn ' t the specimen that last year ' s prolific winner , black caviar , was , and he doesn ' t have that type of prohibitive advantage over the other horses with respect to physique or speed .
thus , it ' s difficult to justify—with any conviction , at least—choosing the odds - on favorite to find the winner ' s circle .
long shot is somewhat of a relative term , because the current odds have the field relatively bunched in that regard . nevertheless , mince is still projected to finish outside the top six and well out of the money .
that shouldn ' t be the case , though . mince is a four - year - old filly with plenty of speed , and her jockey , james doyle , has plenty of experience aboard .
doyle rode mince to victories at her final three races of the 2012 campaign—the finale of which was at the bengough stakes at ascot , where she beat out fellow diamond jubilee stakes competitor soul , a 14 - 1 shot for saturday .
it ' s also been a wonderful run for doyle at royal ascot thus far—he won three races back - to - back on wednesday . combine that with his prior success with mince , and the odds should even drop before the horses take their posts .
three seems to be a common theme here , and don ' t be surprised if mince is in the top three at race ' s end .
the slight slip - up by society rock will allow gordon lord byron to win the featured race of the day at ascot racecourse—and pick up a bit of sweet revenge along the way .
gordon lord byron has had his fair share of close calls at other marquee races involving society rock . at the duke of york stakes , the five - year - old gelding ran third to champion society rock , then finished second to him at the sprint cup .
jockey william buick is still working on his consistency , but although he ' s only 25 years old , he has a great shot at group 1 glory with one of the top horses in the diamond jubilee stakes .
buick also won the race immediately following the sprint cup runner - up effort in the seven - furlong prix de la foret . that is slightly longer than the length at ascot , but the likely blustery conditions and potentially damp track should only play into gordon lord byron ' s favor all the more .
according to itm , tom hogan , who trains gordon lord byron , said after his win at the prix de la foret that he had never had a horse like him . if that ' s not hyperbole , it seems like an ideal situation for gordon lord byron to notch another big group 1 win .
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certain photos copyright © 2018 getty images . any commercial use or distribution without the express written consent of getty images is strictly prohibited .
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the craven breeze up sale is europe ' s premier sale of its kind and takes place at newmarket ' s rowely miles before horses on show return to the nearby headquarters of leading auction house tattersalls ( pictured ) .
lot 99 at the craven breeze up sale pleases her owner , who is looking to make a profit having purchased the filly a year earlier .
the two - year - old chestnut filly was given a run of 600 meters to persuade potential buyers she has a future as a racehorse .
great white eagle , seen here at the go and go round tower stakes at curragh racecourse in kildare , ireland , was also snapped up at the craven sale .
auctioneers at tattersalls hold nine sales a year , selling racehorses at every stage in their career from yearlings to breeding stock .
this year , 128 horses were on offer at tattersalls in april ' s craven sale , and 93 were sold at an average price of $ 200 , 000 each .
buying and selling horses is a risky venture , with the vast majority of horses seeing their value peak before they set foot on a racetrack .
on an april morning at newmarket ' s famous rowley mile , a stretch of turf so hallowed it traces its origins back to britain ' s king charles ii , the fate of lot 99 is about to be decided .
the two - year - old chestnut filly will have just three furlongs , or 600 meters , to persuade potential buyers that she has what it takes to progress to the next stage of her career as a racehorse .
she gallops past the grandstand , hooves thundering and nostrils flaring , hitting a top speed of around 60 kilometers per hour ( 37 mph ) .
as she passes the makeshift winning post , her jockey eases her down to a jog . from here she will return to the warren of stables clustered around terrace house , the headquarters of tattersalls auctioneers , where she will await her destiny .
the craven breeze up sale is europe ' s premier auction of its kind . the top owners , trainers and agents from around the globe are gathered here with one goal in mind : to snap up a future champion .
tattersalls holds nine sales a year , selling racehorses at every stage in their career from yearlings to breeding stock , via two - year - olds and racehorses in training . that ' s nine occasions for potential owners , breeders and trainers to paw over every detail of a horse ' s pedigree , conformation ( or body structure ) and temperament in order to assess whether he or she has what it takes to become the next frankel .
the craven sale is dedicated to unraced two - year - olds . unlike the yearling sales , when buyers must take a gamble on unbroken horses often straight out of the paddock , it allows potential suitors to see the horses gallop . in theory , this removes an element of the risk inherent in the selection process .
when you ' re buying a foal or yearling you ' re a long way from the finished article ,
explains tattersalls marketing director jimmy george .
you have the pedigree and the physical conformation of the horse , the way it moves at the walk , but that ' s it . with two - year - olds , you ' re getting that little bit closer . it ' s a few more pieces of the jigsaw which makes up the quest for the perfect thoroughbred .
harry herbert , racing adviser to sheikh joaan al thani ' s al shaqab operation , agrees that the sale gives buyers a better idea of how the horses have developed physically .
at a yearling sale you can only see them at a walk . here , you can time them over a couple of furlongs and get some idea as to movement ,
herbert says .
with more than 100 horses in training split between the uk and france , al shaqab has ambitions to become one of the dominant forces on the global racing scene , so the stakes are high .
herbert is expecting to walk away with
a handful
of two - year - olds here to add to the sheikh ' s roster .
back at the stables , lot 99 ' s consignor norman williamson reveals he is pleased with his filly ' s work .
that was the plan , to bring her here , and she ' s got it all done now . hopefully people will like her ,
williamson says .
there is certainly a lot to admire . her sire is the illustrious galileo , preeminent stallion of his generation and sire of frankel , regarded by many as the greatest racehorse ever produced . her dam is flamingo sea , a useful racehorse in her own right who has gone on to produce six winners so far as a brood mare .
you don ' t see many galileos breezing ,
enthuses williamson .
she ' s a very good - looking filly , great temperament . we ' ll just have to see .
in 48 hours she , along with 127 other horses , will be auctioned off and williamson will know whether the gamble he took when he purchased her as a yearling has paid off .
williamson is what ' s known in the industry as a
pinhooker
- - someone who buys to sell on for a profit .
the term is said to have come from the tobacco fields of kentucky and describes a speculator who would buy up a farmer ' s young plants and later identify them with a pinned note at market .
if this conjures up images of shadowy figures lurking at the racetrack , hats pulled down low over brows , the reality is more professionalized . pinhookers can add value by overseeing the breaking and training of a young horse with a view to reselling it as race - ready two - year - old .
nevertheless , buying and selling horses is still a risky venture . in an industry where the vast majority of horses will see their value peak before they even set foot on a racetrack , profit lies in this imponderable space between potential and performance . yet pinhooking is still a job that exists on the margins .
it ' s all very well buying a nice , expensive horse but you ' ve got to see some profit in there as well ,
says malcolm bastard , a former jockey who now makes his living pinhooking .
i was at the end of my career and i had a friend who had pinhooked a couple of horses and done pretty good , so i thought i ' d have a go .
a quarter of a century later he has a staff of 30 based at his farm in wiltshire , where the horses he buys as yearlings in the autumn sales are broken in and pre - trained , ready to gallop at the racetrack .
one of the largest consignors , bastard has brought 11 horses to newmarket to sell .
you ' re looking for a strong horse that can take a bit of training and perform well on the track in the spring ,
he explains .
in simple terms , if the horse can run fast and move well , the upside can be substantial . but spotting a horse with the right qualities takes skill , experience and luck .
it ' s up and down with horses ,
concedes bastard .
you have to take the rough with the smooth and hope the good years will carry you through the ones where you don ' t make any money .
most of the horses at these sales began their journey with one of the uk ' s 300 full - time stud farms or 3 , 500 part - time breeders . the breeding industry is the first link in a $ 5 . 8 billion chain that makes up the british racing industry , along with owners , racegoers and gamblers .
in the uk , around 4 , 000 foals are produced annually , most of which will be sold through public auctions like this one . a smaller number are sold privately , while the larger breeding operations such as juddmonte in the uk and coolmore in ireland tend to keep theirs in - house .
as the uk ' s largest bloodstock auctioneer , tattersalls can expect to see a large proportion of these 4 , 000 pass through its iconic domed sales ring at some point in their careers .
the breeding industry is slowly emerging from the effects of the global economic downturn . following a decade of growth in the 1990s , the sector found itself at the sharp end of major falls in the value of bloodstock sales when the financial crisis hit in 2008 .
total revenue from britain ' s two main auction houses , tattersalls and doncaster , slumped by a combined $ 150 million from their peak of $ 509 million in 2007 to $ 358 million in 2008 , according to deloitte ' s economic impact of british racing 2013 report .
since 2012 , however , fortunes have been looking up , exemplified by the sale of hydrogen , another galileo foal , by tattersalls for $ 4 . 4 million - - the highest price paid for a yearling in the world that year .
but hovering over every blockbuster sale like hydrogen is the ghost of the green monkey - - a cautionary tale for any buyer looking to open their wallets on an unraced prospect .
the green monkey was pinhooked as a yearling and sent to florida ' s fasig tipton calder sale in 2006 . impeccably bred ( his grandsire was storm cat , giving him a direct link to both northern dancer and secretariat in his pedigree ) , he fetched a world record price of $ 16 million .


they are small or very small , and have a thorax of two or three segments .

eodiscina includes six families classified under one superfamily , eodiscoidea .

eodiscina

distribution of trilobites of the suborder eodiscina in the erkeket . . . | download scientific diagram
jell , p . a . 1997 . introduction to suborder eodiscina kobayashi 1939 , 383 - 404 .
) . - middle cambrian trilobites of the suborders agnostina and eodiscina from the oslo region , norway . -
eodiscina is a suborder of trilobites , a well known group of marine arthropods . the eodiscina first developed near the end of the lower cambrian period ( late atdabanian ) and became extinct at the end of the middle cambrian .
those of eodiscina , or those of mature ( especially stratigraphically early ) agnostids to cast further light on the problem .
ers . no appendages are known for eodiscina . however , shergold ( 1991 ) has noted a number of features of ontogeny of
agnostids in a cladogram such that they come outside the trilobite clade ( ramskold and edgecombe , 1991 ) . when the superfamily eodiscina is
agnostida - among the early trilobites , with a basic , clamshell - like appearance . suborders agnostina and eodiscina . representative species pictured here : ptychagnostus akanthodes ( agnostina )
proparian – the facial suture ends in front of the genal angle , along the lateral margin . example genera showing this type of suture include dalmanites of phacopina ( phacopida ) and ekwipagetia of eodiscina ( agnostida ) .
abathochroal eyes are found only in cambrian eodiscina , and have around 70 small separate lenses that had individual cornea . the sclera was separate from the cornea , and did not run as deep as the sclera in schizochroal eyes . although well preserved examples are sparse in the early fossil record , abathochroal eyes have been recorded in the lower cambrian , making them among the oldest known . environmental conditions seem to have resulted in the later loss of visual organs in many eodiscina .
suborder eodiscina introduction : there is some controversy over the placement of eodiscina in the agnostida . presence of eyes , sutures , and typical thoracic structure suggest that eodiscina are clearly trilobites ( perhaps akin to ptychopariida ) , and the overall similarity to agnostina ( and placement in agnostida ) prevails in the 1997 systematic treatment of the current treatise . cephalon : with proparian sutures , when present ; some retain eyes ; glabella usually simple , may be narrow and tapering . thorax : 2 or 3 thoracic segments of normal trilobite form , with articulating half - rings pygidium : axis can be long and narrow , extending close to margin , generally distinctly divided into more than 3 ringlike segments ; pleural region segmented in some species , sometimes pygidial segmentation effaced ; border furrows often very deep ; axis sometimes spin - bearing .
the peronopsidae are considered to be the earliest family of the agnostina . this implicates that the earliest peronopsid genus ( archaeagnostus ) probably descended directly from the eodiscoid genus tannudiscus ( weymouthiidae ) . [ 2 ] some scholars do not consider the agnostina true trilobites , and consequently rejected the idea that they were related to the eodiscina . [ 3 ] [ 4 ]
the abatochroal type of eyes is only to be found in a few cambrian trilobites of suborder eodiscina ( kobayashi , 1939 ) . this type consits of up to circa 70 little single lenses , each with it ' s own cornea . the corneal membrane doesn ' t extend inside the eye , and it ends at the edge of the lens . the thin sclera is ending in lenses depth .
trilobites of the suborder eodiscina from the lower cambrian section of the khorbosuonka river ( siberian platform , olenek uplift ) are studied . the stratigraphic distribution of these forms in the section is shown two new species , hebediscus sublongus sp . nov . and korobovia khorbosuonica sp . nov . , are described . this is the first occurrence of the genus korobovia on the siberian platform . the new record provides additional data on morphology and expands the paleogeographic range of the genera represented by the newly described species .
hypoparian or marginal – in some trilobites , dorsal sutures may be secondary lost . several exemplary time series of species show the “migration” of the dorsal suture until it coincides with the margins of the cephalon . as the visual surface of the eye is on the diminishing free cheek ( or librigena ) , the number of lenses tends to go down , and eventually the eye disappears . the loss of dorsal sutures may arise from the proparian state , such as in some eodiscina like weymouthia , all agnostina , and some phacopina such as ductina . the marginal sutures exhibited by the harpetids and trinucleioids , however , are derived from opisthoparian sutures . on the other hand , blindness is not always accompanied by the loss of facial sutures .
fig . 2 . distribution of trilobites of the suborder eodiscina in the erkeket formation of the khorbosuonka river . designations : ( 1 ) dark gray , thick and medium - thick platy clayey limestones ; ( 2 ) limestones with organic detritus ; ( 3 ) light gray , gray , thick - and medium - thick platy limestones ; ( 4 ) dark gray , thick - and medium - thick platy limestones ; ( 5 ) dark gray , thin platy limestones ; ( 6 ) light gray , thin platy limestones ; ( 7 ) gray , medium - thick platy marls ; ( 8 ) light gray , gray , thin platy clayey limestones ; ( 9 ) sampling levels and sample nos . ; collection nos . of specimens are in parentheses .
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( such as our own ) can change shape ( accommodate ) to focus on objects at varying distances . trilobite eyes , in contrast , had
( two lens layers of different refractive indices acting in combination ) corrected for focusing problems that result from rigid lenses . the shapes of some trilobite lenses , in fact , match those derived by optical scientists over 300 million years later to answer similar needs . compare , for example , the optical designs of the 17th century physicists descartes and huygens shown below , with those of two trilobite species . the result is that , even without the benefit of accommodation , the rigid trilobite doublet lens had remarkable
light ray paths ( yellow ) entering the lens from the left come into focus a short distance to the right of the lens ( blue ) .
, an intralensar body ( white ) further corrects focus after passing through the outer lens layer ( blue ) .
descartes ' lens design for minimal aberration ( above left ) is found in the lens of the trilobite dalmanitina ( right ) both images ©1999 , 2000 by s . m . gon iii , modified from clarkson and levi - setti 1975
that covers all of the lenses . these lenses are generally hexagonal in outline and range in number from one to more than 15 , 000 per eye ! schizochroal eyes on the other hand are made up of a few to more than 700 relatively
into the sclera , where it is called intrascleral membrane . the abathochroal eye ( jell 1975 ) is seen in only a few
, and the corneal membrane does not extend downward , but ends at the edge of the lens . the table below illustrates and contrasts the characters of the three eye types .
how did schizochroal eyes evolve ? all early trilobites ( cambrian ) , had holochroal eyes and it would seem hard to evolve the distinctive phacopid schizochroal eye from this form . the answer is thought to lie in ontogenetic ( developmental ) processes on an evolutionary time scale . paedomorphosis is the retention of ancestral juvenile characteristics into adulthood in the descendent . paedomorphosis can occur three ways : progenesis ( early sexual maturation in an otherwise juvenile body ) , neoteny ( reduced rate of morphological development ) , and post - displacement ( delayed growth of certain structures relative to others ) . the development of schizochroal eyes in phacopid trilobites is a good example of post - displacement paedomorphosis . the eyes of immature holochroal cambrian trilobites were basically miniature schizochroal eyes . in phacopida , these were retained , via delayed growth of these immature structures ( post - displacement ) , into the adult form .
although eyes are normally an extremely important survival feature , there are situations under which loss of eyes might occur . for example , trilobites that took advantage of deep - water
( bottom - feeding ) habitats where light was dim or lacking might have gradually lost their eyes without suffering an adaptive disadvantage . such eyeless trilobite assemblages are called
are repeatedly seen in a variety of trilobite orders , and two examples are shown below . in both cases , these are devonian trilobites that started with ancestors bearing large , functional eyes . in one sequence , eyes of a phacopid clade were lost , and
associated with eyes were also reduced and marginalized . in the other example , involving a proetid clade , eyes were also reduced and lost , but the basic facial suture pattern was retained . in the figures below ( after fortey & owens 1999 , citing feist 1995 ) , the eyes are shown in blue and facial sutures in red .
the image to the left is a remarkable multiple of conocoryphe sulzeri , a secondarily eyeless ptychopariid from the czech republic .
reduction of eyes and a migration forward on the cephalon is seen in the descendant cryphops .
eventually the eyes were lost althogether and the sutures were left along the anterior margin of the cephalon in the genus trimerocephalus .
although the eyes are entirely lost in this pteroparia species , the facial suture patterns are largely unchanged .
all line drawings this page ©1999 - 2014 by s . m . gon iii
, rimmed with an eyeshade . this is another recent documentation of a remarkable development of the optical organs in trilobites .
. effect of paedomorphosis in eye reduction on patterns of evolution and extinction in trilobites .
the schizochroal eyes of phacopids have attracted research for over 150 years , and the arrangement and number of lenses in the holaspid eye has been subject to analyses exploring their utility in distinguishing between populations , species , and higher taxa , as well as the amount of variation that might be found within populations . indeed , there are studies that have demonstrated that there can be differences between the number and arrangement of lenses between the two eyes on a single specimen !
it was pioneers such as steininger ( 1831 ) and clarke ( 1889 ) that first diagrammed the arrangement of lenses and suggested that these might be useful in classification , but clarkson ( 1966 ) who established the system of charting and counting dorso - ventral files ( dvf ) of lenses . the classic study of niles eldredge ( 1972 ) used dvf among other characters to distinguish the species and subspecies in north american
, bearing the largest number of files . he concluded that p . rana and p . iowensis were only distantly related , a conclusion also reached by struve ( 1990 ) , who erected genus
from the haragan formation in oklahoma . later , ramsköld and werdelin ( 1991 ) revised that complex , recognizing not only separate species , but assigning them to two different genera :
, with 6 - 7 lenses per file for the
large - eyed
morph .
thomas , a . t . 2005 . developmental palaeobiology of trilobite eyes and its evolutionary significance .
steininger , j . 1831 . observations sur les fossiles du calcaire intermediaire de l ' eifel .
sem images of the trilobite schizochroal eye courtesy of dr . riccardo levi - setti from his superb book
trilobites
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( left ) . this typical primitive morphotype had a small pygidium , well developed eye ridges , a simple , lobed glabella , several thoracic segments , and a rather flattened body form .
were characterized by this primitive form . among the over 20 , 000 species of described trilobites there are species in which aspects of morphology have diverged greatly from the primitive state . these are discussed in fortey & owens 1997 ( see citations below ) .
shapes and furrow patterns of the glabella , and the shape and placement of eyes and eye ridges of course also ranged widely . an analysis of morphological diversity of trilobite forms showed that increasing from the cambrian , there was a peak in morphological diversity in the ordovician ( which parallels a peak in overall diversity of trilobites families ) that decreased only as overall trilobite diversity decreased toward their extinction in the late permian .
within this diversification , there were a number of evolutionary trends in morphology that developed in unrelated clades , creating homeomorphy ( attainment of similar forms in unrelated groups ) . these homeomorphic trends , such as effacement , increased spinosity , reduction in body size , streamline shape , and loss of eyes , can not be reliably or consistently used to assess higher systematic relationships . instead , these features can tell us about selective pressures on trilobites and how similar solutions were derived in parallel by different evolutionary lineages . each of these is discussed below , and examples are given from different orders .
effacement in several trilobite orders , but perhaps most notably among the agnostida , corynexochida ( suborder illaenina ) , and asaphida , effacement of cephalic , pygidial , and even thoracic furrows is not uncommon . this loss of surface detail can be confounding to systematics , since effaced features ( for example loss of glabellar details ) can mask evidence of relationships . some workers suggest that effacement is an adaptation related to a burrowing lifestyle , especially in illaenina , but such effacement might also play a role in streamlining of pelagic asaphida , and is also seen in many agnostida ( which may have been planktonic ) . no single selection pressure seems to have been responsible for the effaced morphotype .
effaced trilobites , such as those above , can be difficult to classify , since they lack key characters .
spinosity the development of spines is commonly thought of as primarily a defensive adaptation , and increased spinosity is seen in a wide variety of trilobite species . alternate hypotheses for the adaptive significance of spines include stabilization structures on a loose silty substrate ( e . g . genal spines of trinucleid asaphida , such as ampyx , below ) , and flotation / stabilization structures for slow - swimming taxa ( e . g . , odontopleuroid lichida such as leonaspis at left ) . spines may originate from just about any part of the exoskeleton , especially the margins . sometimes these patterns provide consistent and diagnostic characters for higher classification ( for example , the pattern of pygidial spines among odontopleuroid lichida ) . however , as seen in the spinose species below , development of spines occurs in many orders of trilobites .
spinose trilobites are a clear indication that it was dangerous world in the paleozoic , in which an unarmed trilobite might likely be swallowed whole .
( just about 1 millimeter at maturity ) . the general argument for evolution of small size typically evokes the numerous microhabitats of complex marine systems , coupled with a correlation of size to rapid maturity ( early maturation means smaller size at adulthood ) . when this reduction is due to
, for example , has only two thoracic segments at maturity , yet is not a member of the order agnostida ( formerly thought to be the only order bearing three or fewer thoracic segments ) , but of corynexochida . the entire order agnostida is composed of small species that may have originated as a miniaturized and specialized early offbranch of the redlichiida or ptychopariida .
in a complex marine environment , many niches ( physical and ecological ) are available for small species .
atheloptic morphology reduction and loss of eyes in trilobites has been discussed elsewhere , and secondary reduction and loss of eyes is thought to be a trend among benthic species living in deep , poorly - lit or aphotic habitats . in these deep water biotopes , blind or nearly - blind trilobites are the dominant element . typically , these atheloptic species have close relatives in which eyes are of normal size and function . it is interesting to note that another trend of deep bottom habitat adaptation is an increase in the number and width of thoracic segments , which might be related to specialized feeding adaptations ( see olenimorph section below ) .
atheloptic trilobites had little use for eyes on the dark bottoms of ancient seas .
pelagic morphology there are a number of trilobites that have developed extremely large eyes and elongate , streamlined body shape associated with swimming in the photic water column . the paleogeography of some of these pelagic species ( for example , carolinites , shown at left ) , suggests that their swimming abilities were good enough them to spread into a global oceanic distribution .
pelagic ( oceanic free swimming ) trilobites typically had large eyes and an elongate body form .
numerous segments with wide pleurae covered enhanced gills for better oxygen absorption and perhaps for symbiotic bacteria to live .
pitted fringe an expansion of the cephalon into a concave chamber perforated by numerous fenestrations is thought to be an adaptation related to filter - feeding . this morph has arisen in at least two unrelated groups : trinucleioid asaphida and members of the order harpetida . in both cases the cephalon is the dominant part , with transverse thoracic segments and an unremarkable pygidium . long genal spines or genal prolongations are also notable in this morphotype . they are thought to help stabilize the trilobite during filter - feeding .
fortey , r . a . , and r . m . owens . 1999 . feeding habits in trilobites .
fortey , r . a . , and r . m . owens . 1997 . evolutionary history . in kaesler , r . l . , ed . treatise on invertebrate paleontology , part o , arthropoda 1 , trilobita , revised . volume 1 : introduction , order agnostida , order redlichiida . xxiv + 530 pp . , 309 figs . the geological society of america , inc . & the university of kansas . boulder colorado & lawrence , kansas .
paterson , j . r . & g . d . , edgecombe . 2006 . the early cambrian trilobite family emuellidae pocock , 1970 : systematic position and revision of australian species .
the trilobites of order agnostida ( pronounced ag - nós - t - eh - da ) appeared in the lower cambrian where they were diverse and ubiquitous , and declined to become rare in the ordovician prior to their complete extinction by the end of the ordovician . there is debate about whether agnostids were benthic or pelagic , and the systematic position of order
* different taxonomies are found , most recently with trilobites contained in superclass arachnomorpha in subphylum schizoramia .
agnostida remains unsettled , if not contentious . the agnostids were mostly blind and exhibit a strong symmetry of cephalon and pygidium size , making it hard to distinguish front from rear .
a highly widespread paleo - geographic dispersion was long considered consistent with a pelagic , planktonic lifestyle . in contrast , a lack of eyes in most species suggests a benthic lifestyle in deep , cold water on the ocean floor in minimal or no light where they fed on detritus . the agnostids are often found in dense mass mortality assemblages and in association with other benthic trilobites , particularly those of order ptychopariida . additionally , their diminutive size , low mass and general morphology are hydrodynamically inconsistent with a swimming pelagic mode of life . a weight of evidence tends to support that the agnostida were benthic , but more data are needed ; perhaps the little agnostida made their living in different or multiple ways , depending on their age , or on the paleoenvironment where they lived .
original russian text © i . v . korovnikov , 2007 , published in paleontologicheskii zhurnal , 2007 , no . 6 , pp . 24–30 .
s . bengtson , s . conway morris , b . j . cooper , et al . ,
w . t . chang , “some lower cambrian trilobites from western hupei , ” acta palacontol . sin .
e . s . cobbold , “additional fossils from the cambrian rocks of comley , schropshire , ” quart . j . geol . soc .
r . d . hutchinson , “cambrian stratigraphy and trilobite faunas of southeastern newfoundland , ” bull . geol . surv . canada
v . v . khomentovskii , m . a . semikhatov , and l . n . repina ,
( akad . nauk sssr , moscow , 1960 ) , vol . 4 [ in russian ] .
m . n . korobov , “biostratigraphy and myomere trilobites of the lower cambrian of mongolia , ” tr . ssmge
( biostratigraphy of the cambrian and carboniferous of mongolia ) , 5–108 ( 1980 ) .
i . v . korovnikov , “trilobite assemblages and biostratigraphy of the lower cambrian section of the khorbosuonka river ( olenek uplift , northeastern siberian platform ) , ” geol . geofiz . , no . 10 , 1377–1391 ( 1998 ) .
i . v . korovnikov , “new data on biostratigraphy of the lower and middle cambrian section of the khorbosuonka river ( olenek uplift , northeastern siberian platform ) , ” geol . geofiz . , no . 9 , 826–836 ( 2002 ) .
( niiga , leningrad , 1962 ) , pp . 29–78 [ in russian ] .
l . n . repina , v . v . khomentovskii , i . t . zhuravleva , and a . yu . rozanov ,
l . n . repina , n . p . lazarenko , n . p . meshkova , et al . ,
n . s . shaler and a . f . foerste , “on the geology of the cambrian district of bristol county , massachusetts , with a preliminary description of north attleborough fossils , ” harvard coll . mus . comp . zool . bull .
, ed . by r . l . kaesler ( univ . kansas press , lawrence , 1997 ) .
i . t . zhuravleva , n . m . zadorozhnaya , d . v . osadchaya , et al . ,
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, but this turns out to have been mistaken ; an artifact of preservation . the first recorded cambrian outcrops only preserved species with hard , shelly parts , such as trilobites , brachiopods , mollusks , and echinoderms . when the
of trilobites , rather than their descendants ( see diorama below ) . trilobites are now considered
in this classification , trilobites are a class within the superclass arachnomorpha , one of two superclasses within the subphylum schizoramia of the phylum arthropoda . ©2000 by s . m . gon iii , created in macromedia freehand 8 . 0
trilobites are arachnomorphs , but moreover , they belong to a clade distinct from that which contains the chelicerates ( which includes modern groups such as arachnida and merostomata ) . both the chelicerate clade and the trilobite clade are well represented in the cambrian species assemblages at the burgess shale and chengjiang . the clade labeled
indeterminate arachnomorpha
should more appropriately be called
basal arachnomorpha
( cotton , pers . comm . 2003 ) ©2003 by s . m . gon iii , created in macromedia freehand
in contrast , the “trilobite clade” includes arachnomorphs lacking a telson , and with dorsal segments that may cover more than one pair of legs . the pygidium of trilobites is a good example of a fused single dorsal tergite covering several pairs of legs . taken to extreme , the single - piece carapace of tegopelte , and the two - piece carapace of naraoia also represent this trend of decoupling of dorsal tergites with limb pairs ( see below ) . we owe much of our recent understanding of the trilobite clade to the exceptionally well preserved assemblages of arthropods from chengjiang , which greatly complements the assemblage from the burgess shale .
this image ©2002 by s . m . gon iii , created in macromedia freehand
features of the “trilobite clade” most of the arachnomorph trilobite clade share features in common with trilobites , such as a hypostome , 3 - 4 pairs of post - antennular legs under the cephalon , similar limb structure , etc . such similarities have led to proposals to include some trilobite - like arachnomorphs in the class trilobita ( e . g . , the naraoiidae ) . however , some recent cladistic analyses of arachnomorph taxa have elevated helmetiidae as a clade closely aligned with the trilobites ( see figure above , and discussion below ) , which would create a paraphyletic situation if the naraoiids are also considered trilobites . it seems more reasonable to recognize the similarities of members of the “trilobite clade” of the arachnomorpha , while also recognizing their distinctiveness .
below , each of the members of the
trilobite clade
are discussed , and the constituent species are pictured . several different sources were used to compile the reconstructions pictured here , and i am pleased to note that this site is the first publication ( web or otherwise ) to picture all of the pertinent genera and species of the
trilobite clade
in one place , and in a consistent style .
was described ( above , left ) , it was known from only a single , incompletely preserved specimen that displayed neither complete limbs nor antennae . the remarkable chengjiang biota includes four species of helmetiids , clearly similar to
, and demonstrating antennae , trilobite - like limbs , stalked ventral eyes , and an anterior lobe . most of the species show a distinct head shield , thorax , and tail shield , very similar to trilobites . the exception ,
( described below ) . in several recent cladistical analyses , helmetiids emerge as the arachnomorph clade most similar to trilobites , displacing the naraoiidae as the clade nearest to trilobites , and suggesting that the idea of naraoiids as a
ninth order
of trilobites should probably be set aside .
zhang & shu 2005 , was tentatively described as an aglaspid ( a member of the
chelicerate clade
) . however , paterson et al 2010 suggested that
bears characters that suggest more affinities with the
trilobite - like clade .
they place
as basal helmetiid , because of similarities in limb morphology and anteriorly reflexed thoracic segments . however , it also seems to bear characteristics of xandarellids ( see below ) , especially in lack of a large tail shield , an axial posterior spine , lack of a discernable anterior lobe , and ventral eyes occupying dorsal bulges in the cephalon ( as in
clearly revealed stalked ventral eyes , and an anterior lobe similar to that found in helmetiids . my reconstruction of
presumes that it also bears similar structures , although they are not clearly visible in the burgess type specimen . compelling similarities between
( see above ) , particularly the splayed tergal boundaries that fail to reach the lateral margins , indicate the close relationship between helmetiids and tegopeltids . indeed , the only diagnostic feature of tegopeltids is that the margin is entire , smooth , and unadorned by spines or serrations . it is clear that helmetiidae and tegopeltidae form a single monophyletic clade .
, but was recently split out on the basis of its dissimilar antennal orientation ( see above , right ) . when
as a
soft - bodied trilobite .
a fuller discussion of the relationship of naraoiids to trilobites is presented on a
the family liwiidae ( sometimes subfamily liwiinae of the family naraoiidae ) is comprised of naraoiid - like species that are distinguished from naraoiids in bearing thoracic tergites . some , like
, nileidae ) , but as in naraoiids , are primarily eyeless , and lack a well - defined axis ( in addition to being uncalcified ) . the liwiidae are geographically diverse , being recorded from a variety of sites outside of either the burgess shale or chengjiang deposits , including one other cambrian
was found ) . despite a diversity of form , the liwiidae are considered most closely related to the naraoiidae . however it remains to be seem whether the general similarities reflect true homologies .
in 2010 , a new family of nektaspida , the emucaridae , were described via two new genera of soft - bodied arachnomorphs from australia ' s kangaroo island ( paterson et al 2010 ) . this family is distinguished by bearing a small number of thoracic segments , with articulations poorly developed , and with no strong differentiation between either the cephalon in front nor the tail shield behind . this distinguishes the family from the liwiidae , which typically show distinct cephalic , thoracic and tail shield morphology . the emucaridae are similar to other arachnomorphs in several ways . incomplete articulation of the tail shield is similar to that seen in tegopeltids , and the smooth transitions between cephalon , thorax and tail shield is similar to that seen in some xandarellids , such as
. even where the tail shield is not well - developed , there is a decoupling of tergites and somites , so that posterior tergites cover increasing numbers of limbs ( each limb pair corresponding to a somite ) . there are no xandarellids documented from the burgess shale . all the known species are from chengjiang . they point to the value of this exceptional cambrian
, from which an entire clade of trilobite - like arachnomorphs was added to the fossil record .
of course , no matter how similar the other trilobite clade arachnomorphs are to true trilobites in morphology , there are a number of features that trilobites share with no other arthropod group . these are discussed below :
) . the classification of trilobites within the arthropoda has generated much controversy , much of which is still not completely resolved ( see above ) . whatever their higher position among arthropoda , there are a number of
together with the organization of the body into three anterior - posterior divisions ( cephalon , thorax , and pygidium ) , and the three longitudinal lobes ( axial lobe and two flanking pleural lobes ) , the body features on this page serve to readily distinguish trilobites from all other known arthropod groups .
while other compound eyes are found in cambrian arthropods , only those of trilobites have corneal surfaces composed of prismatic calcite lenses ( with the crystallographic axis normal to the lens surface ) .
circumocular sutures : in cambrian holochroal trilobite eyes , a suture around the edge of the shared corneal surface assisted in molting of holaspid trilobites . in post - cambrian trilobites this feature is secondarily lost , leaving the corneal surface attached to the librigena .
rostral plate : a ventral anterior plate separated from the rest of the cephalic doublure by sutures is very well developed in primitive trilobites ( e . g . , redlichiida ) , narrower in other trilobite orders , and secondarily lost in some advanced forms ( e . g . , asaphida and phacopida ) all images ©1999 - 2002 by s . m . gon iii unless otherwise noted
calcified cuticle : trilobites bear a rather pure calcareous cuticle that ends ventrally at the inner edge of the doublure . although a few other arthropod groups calcify , none do so the same way as trilobites . crustacea , for example , are calci - fied ventrally and post - orally , so appendages are calcified .
, his 2001 review of trilobite classification , the 2002 splitting of the harpetida from the ptychopariida , and recent acknowledgement of the order odontopleurida suggests an arrangement that looks something like the figure below . a discussion of the evolutionary trends and relationships of the orders follows .
systematic relationships and chronological extent of the trilobite orders image above ©2009 by s . m . gon iii , created using macromedia freehand and paintshop pro thanks to nigel hughes for stimulating discussions leading to revisions of this figure . in june 2007 , a version of this figure was published in hughes 2007 . in 2008 odontopleurida was recognized . in 2009 ptychopariida established as cobasal with redlichiida as earliest trilobite order .
the status of the order lichida is likewise not entirely clear . in the first trilobite treatise ( 1959 ) , an order odontopleurida was recognized , including the large family odontopleuridae . thomas & holloway ( 1988 ) acknowledged that the lichidae and odontopleuridae are related , but that their post - cambrian evolutions have been distinct . when fortey ( 1997 ) added damesellidae to the order lichida , it was indicated that they are more similar to odontopleuridae than to lichidae . if two orders are recognized , it may be lichidae + lichakephalidae = lichida , and odontopleuridae + damesellidae = odontopleurida . however , the cambrian family lichakephalidae may be paraphyletic , with some of its genera similar to lichidae and others more similar to odontopleuridae . in particular , some workers reject the synonymy of eoacidaspididae with lichakephalidae , and note that at least some genera in eoacidaspididae are close to odontopleuridae .
on what basis , then , are the orders defined ? no single character ( e . g . , facial sutures ) dominates in higher level classification . instead , such characters as facial sutures , glabellar shape and pattern of lobation , eyes , thoracic features and numbers of thoracic segments , pygidial shape , size and segmentation , and spinosity all play a role in helping define the orders . in addition , note that hypostomal conditions and shared ontogeny play an important role in defining the orders of trilobites . that is why for each of the order fact sheets , as many of the above details are provided as possible . as a synopsis , here are brief statements regarding each of the trilobite orders :
redlichiida - including the most primitive trilobites from the lower cambrian . suborders olenellina and redlichiina . representative species pictured here : redlichia sp . ( redlichiina )
corynexochida - an often spiny group united by a shared hypostomal attachment . suborders corynexochina , illaenina , and leiostegiina . representative species pictured here : kootenia sp . ( corynexochina )
lichida - some of the most ornately sculptured species fall into this group . suborder lichina ; families lichidae and lichakephalidae . representative species pictured here : arctinurus boltoni ( lichioidea )
phacopida - the well - known phacops , with its beautiful compound eyes belongs here . suborders calymenina , phacopina , and cheirurina . representative species pictured here : phacops sp . ( phacopina )
proetida - includes some of the last trilobite species before the permian extinction . suborder proetina , with three superfamilies . representative species pictured here : proetus granulosus ( proetoidea )
asaphida - all share a ventral median suture , and most a similar development . suborder asaphina , with six superfamilies comprising ~ 20 % of all trilobites . representative species pictured here : homotelus sp . ( asaphoidea )
ptychopariida - bearing the
generic trilobite
body plan , but many weird variations ! suborders ptychopariina and olenina ( harpina has been elevated to order harpetida ; see below ) representative species pictured here : modocia sp . ( ptychopariina )
harpetida - bearing the distinctive , broad , often intricately pitted , cephalic fringe . in 2002 , split out of the ptychopariida and elevated from suborder to full order . representative species pictured here : eoharpes sp .
nektaspida - the so called
soft - shelled trilobites
such as naraoia have been classified as an order of trilobites by some . click on the image or link to learn more about them , and to see how they are handled in the 1997 treatise .
chen , j . & g . zhou . 1997 . biology of the chengjiang fauna . in the cambrian explosion and the fossil record . bulletin of the national museum of natural science 10 : 11 - 106 .
cotton , t . j . , and s . j . braddy . 2004 . the phylogeny of arachnomorph arthropods and the origins of the chelicerata . transactions of the royal society of edinburgh : earth sciences , 94 : 169–193 ,
ebach , m . c . & k . j . mcnamara . 2002 . a systematic revision of the family harpetidae ( trilobita ) . records of the western australian museum 21 : 235 - 67 .
edgecombe , g . & l . ramskøld . 1999 . relationships of cambrian arachnata and the systematic position of trilobita . j . paleontology . 73 ( 2 ) : 263 - 87 .
fortey , r . a . 1997 . classification . in kaesler , r . l . , ed . treatise on invertebrate paleontology , part o , arthropoda 1 , trilobita , revised . volume 1 : introduction , order agnostida , order redlichiida . xxiv + 530 pp . , 309 figs . the geological society of america , inc . & the university of kansas . boulder , colorado & lawrence , kansas .
fortey , r . a . 2001 . trilobite systematics : the last 75 years . j . paleontology . 75 ( 6 ) 1141 - 51 .
lauterbach , k . - e . 1983 . synapomorphien swischen trilobiten - und cheliceraten - sweig der arachnata . zoologischer anzweiger 210 : 213 - 38 .
paterson , j . r . , g . d . edgecombe , diego c . garcia - bellido , j . b . jago & j . g . gehling , 2010 . nektaspid arthropods from the lower cambrian emu bay shale lagerstatte , south australia , with a reassessment of lamellipedian relationships .
størmer , l . 1944 . on the relationships and phylogeny of fossil and recent arachnomorpha . a comparative study on arachnida , xiphosurida , eurypterida , trilobita , and other fossil arthropoda . skrifter utgitt av det norske videnskaps - academi i oslo . i . matematisk - naturvidenskapelig klasse 5 : 1 - 158 .
wills , m . a . , d . e . g . briggs , r . a . fortey , m . wilkinson & p . h . a . sneath . 1998 . an arthropod phylogeny based on fossil and recent taxa . in : g . d . edgecomb , ed . arthropod fossils and phylogeny . columbia university press , n . y .
zhang x . l . & d . g . shu . 2005 . a new arthropod from the chengjiang lagerstatte , early cambrian , southern china .
* several alternative taxonomies are found in past and current literature . for example , trilobites are sometimes found placed in arthropoda subphylum schizoramia within superclass arachnomorpha . * * some authors argue that a separate order odontopleurida should be separated from order lichida , but the concention is not followed here pending settlement of the science .
abstract - the progress achieved in trilobite systematics over the last 75 years is briefly reviewed . different approaches to phylogenetics have
influenced the way trilobites have been classified . classical evolutionary taxonomy , the stratigraphical approach , and cladistics have all
contributed in different ways to the current classification , which has evolved piecemeal , and is still unsatisfactory is some ways . nonetheless ,
silificified material . trilobites are a well - defined clade within a larger arachnomorph group . agnostida have been excluded from trilobita , but
relevant ontogenies . it is very likely that post - cambrian glades
root
deeply into the cambrian . the coherence , or otherwise , of proetida ,
asaphida , corynexochida and the lichid / odontopleurid groups will be resolved by such studies . the problems of paraphyly in ptyc
half an century later ; they comprise the raw material upon which hypotheses of trilobite relationships are founded . it is also pertinent that
almost any laptop - - was by fortey and chatterton ( 1988 ) to analysis relationship in asaphida . ramskold and werdelin ( 1991 ) has been cited as
an exemplary phylogenetic analysis by smith ( 1994 ) , and so on . in this paper i shall examine some of the history of progress in trilobite
that most workers can accept have not been made . new insights have arisen , and consensus is emerging , albeit slowly . the journal of
epted for nearly two hundred years . what has been at issue is the place that the group occupies
within the arthropoda , sensu lato . inevitably this is entangled with the phylogenetics of this greater group , itself a perennial problem . as far as
( horseshoe crabs and arachnids ) ? of the taxonomic status of the trilobita not much need be said . a group comprising several thousand genera
constitution of trilobite as a group . - the coherence of trilobita as a clade has been challenged by lauterbach ( 1980 , 1983 ) , who noted a number
of characters that allegedly linked primitive olenelloids with limuloids in preference to the rest of the trilobite . for example he identified a
posterior spine on the middle of the axis in olenellus thompsoni with the telson spine of limuloids . he stressed the importance of the macropleural
segment in olenelloids in his interpretation of segmental homology . fortey and whittington ( 1989 ) countered this assertion by listing a greater
these synapomorphies effectively defined trilobita , at least in the sense of calcified exemplars . characters cited included : the calcified structure
pygidium having more than one segment . ramskold and edgecombe ( 1991 ) challenged a number of these characters but
view of trilobite monophyly ( see also edgecombe and ramskold , 1999 ) . even if lauterbach were mistaken it was interesting that he emphasised
trilobita related to other arthropods . - stormer ( 1933 ) followed earlier workers such as garstang in considering that trilobites were related to
chelicerata , especially by comparison with limulus . garstang had noted such features as the so - called
trilobite larva
of limulus in support of
his claim . the structure of the trilobite limb had been established in essentials by beecher ( 1894 ) . however , redescription of the cambrian
whittington and almond ( 1987 ) served to establish the structure of the trilobite ' s biramous limbs in some detail . trilobites are generally
implication being that this was a primitive design for an arthropod . this group was recognized in the 1959 treatise on invertebrate paleontology ,
part 0 ( moore , ed . , 1959 ) . following manton ' s ( 1977 ) review of arthropod classification there was a period in the 1970s when arthropod
ancestor . manton claimed this for the main groups of arthropods she recognised , trilobites being one of them . this
trilobitomorph limb , and differences in segmentation of the cephalic region being a subsequent specialization .
burgess shale animals ) in relation to their possible living relatives . the first of such analyses was that of briggs and fortey ( 1989 ) , which
have improved upon the character codings ( e . g . , wills et al . , 1998 and references therein ) , and further improvements are doubtless possible , but
contrary view see fryer , 1998 ) . the position of the trilobites in cladograms further suggests to some that the view of the origin of the group as
cambrian of china ( chen , edgecombe , and ramskold , 1997 ; chen et al . , 1997 ;
cambrian to late ordovician ( fortey and theron , 1994 ) and the order nektaspida has been applied to it . however , if naraoiids are included
apply trilobita to the calcified clade , within the larger group , in its classical usage .
treatise on invertebrate paleontology ( whittington et al . , 1997 ) . for many years agnostids were known from exoskeletons alone . they were
rasetti and theokritoff ( 1967 ) ; robison ( 1972a ) discovered the hypostome for the first time . the appendages of agnostids proved elusive but were
from the upper cambrian orsten nodules of sweden . these appendages proved to be very different from those previously described from
ose of conventional trilobites , and they have a unique post - - cephalic aperture when enrolled .
the question of how secondarily specialised their appendages might be . some workers have regarded agnostids as paedomorphic - that is , they
hose of a larval trilobite . as yet , no protaspis or early meraspis of a ' conventional '
pagetia which serve to separate eodiscoids from the agnostina . the systematic position of agnostina is probably
and a fuller analysis than that of fortey and theron ( 1994 ) is desirable . it would assuredly be relevant to discover limbs of larval trilobites , or
there have been several different approaches to classification and phylogenetics in trilobite studies over the last 75 years . these may be broadly
characterised by three paradigms , which follow one another in time , but with considerable overlap .
1 . classical evolutionary taxonomy . - early issues of the journal of paleontology are devoid of trilobite articles . however , in the twenties and
importance of suture patterns , and recognition of taxa above family level . their approach was typical of
demonstrated how thoracic segments are released from the front of the protopygidium during early ontogeny . stubblefield ( 1936 ) produced a
a group ) by showing that the assemblage was certainly polyphyletic . he also criticised the over - simple use of proparian and opisthoparian suture
patterns as classification tools , and gave reasons why the former should not be primitive , as had been claimed . phylogenetic arguments broadly
2 . the stratigraphic paradigm . - perhaps beginning with lochman ( 1936 ) the journal of paleontology began to publish an extensive series of
papers descriptive of north american trilobites . many of these were of stratigraphic importance , a use which continues today . prominent among
important papers in the journal . throughout this period similar monographs published as us geological survey professional papers ( now sadly
discontinued ) and by state surveys added enormously to the trilobite database . however , most taxa were described from cranidia and pygidia
reference to stratigraphical succession . the point was made very clearly by rasetti ( 1972 ) who ,
studies in the great basin and elsewhere . palmer ' s ( 1965b ) description of pterocephaliid biomere trilobites explored the taxonomic consequences
biostratigraphical level . under this paradigm stratigraphic collecting to reconstruct phyogenies became a sine qua non for classification . many of
the taxa included in the 1959 treatise , part o ( moore , ed . ) , were erected during this monographic period . the stratigraphic paradigm extended
in the manner of this paradigm . similar morpho - phylograms continued to be published for silurian ( e . g . , see lane , 1971 ) and devonian ( lutke ,
reasons , of which the most important was the necessity to invoke enormous convergence between taxa to either side of biomere boundaries , e . g . ,
in the family solenopleuridae . it seemed more parsimonious to assume that such striking resemblance between taxa above and below these
boundaries are likely to indicate genuinely close relationship . furthermore , the stratigraphic ranges of poorly definable cambrian genera were
( ludvigsen et al . , 1989 ; westrop , 1995 ) . yet although the
durations are short ( 2 - 3 m . y . ) . this applies to distinctive ( highly apomorphic ) genera as much as to those with more
generalized
morphology .
biomere boundaries represent elevated turnover intervals that can be recognized at species / generic level . unless cambrian workers draw their
single family , and the stratigraphy - based phylogenies therein are plausible . it may be significant that olenids occupied a specialised habitat with
continuous sedimentation and an unparalleled record . certain agnostid stratigraphic phylogenies - e . g . , ancestor - descendant relat
glyptagnostus stolidotus and g . reticulatus ( opik , 1979 ) - have been repeatedly observed worldwide . palmer ' s ( 1965 ) phylogeny of pterocephalia
appears to be robust . strusz ' s ( 1980 ) phylogeny of silurian encrinurids has been largely confirmed by subsequent cladistic analysis . but as a
general reference for trilobite classification the reconstruction of stratigraphy - based trees has not worked .
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cephalon : no facial sutures or eyes ; glabella divided by transglabellar suture into anteroglabella and posteroglabella ; cephalothoracic aperture present . thorax : 2 thoracic segments bearing distinctive articulating structures , but no articulating half - ring on anterior thoracic segment . pygidium : axis usually wide , inflated , 3 or fewer segments , one of which usually carries a tubercle ; posterior axial rings effaced ( posteroaxis ) ; pygidial margin often bearing posterolateral spines . cuticle thin . superfamilies : agnostoidea and condylopygoidea ( each described below ) .
superfamily condylopygoidea cephalon : with transversely oriented basal glabella lobes , separated by medial plate , together forming a clear occipital structure , anterior glabellar lobe laterally expanded around anterior end of posteroglabella , sometimes separated by a median sulcus . thorax : as in typical agnostina . pygidium : axis with 3 - segmented anteroaxis ; broad , posteriorly rounded posteroaxis . family : condylopygidae genera : condylopyge ( / paragnostus ; fallagnostus ) , miraculaspis , pleuroctenium ( = dichagnostus ) .
the arrangement of genera and families for suborder agnostina is via jell and adrain 2003 , superceding some of the classification of agnostida in the 1997 treatise . for listed genera , synonyms are shown in parentheses .
( see figure at right ) were first documented ( muller and walossek 1987 ) , they proved very different from previously described trilobite limbs ( e . g . , those of
, etc . ) . this cast doubt about the presumed inclusion of the suborder agnostina within the class trilobita . however , no appendages from fully grown holaspid agnostines have ever been documented , leaving room for the contention that larval limbs may not resemble those of adults . the argument has also been made that agnostid trilobites may represent evolution via progenesis ( maturity achieved while the body retains immature morphology ) , which suggests that even adult agnostines could retain the presumed larval form . no limbs of protaspides or meraspides of
conventional
trilobites has been described either , so the speculation that the limbs of
cotton , t . j . & r . a . fortey . 2005 . comparative morphology and relationships of the agnostida .
fortey , r . a . 2001 . trilobite systematics : the last 75 years .
ramskold , l . & g . d . edgecombe . 1991 . trilobite monophyly revisited .
it has been suggested that agnostida , via their small size , widespread distribution , and large numbers , might have been planktonic . however , there are a number of logical inconsistencies with this contention ( via pers . comm . brian chatterton 2003 ) :
1 ) most agnostida are blind , while most modern pelagic arthropods are sighted .
2 ) they are often found complete , articulated , right way up among complete articulated , right way up ptychopariid and other trilobites that everyone would accept as benthic .