heliothis peltigera , the bordered straw , is a species of moth of the family noctuidae .

it is found in southern europe and the near east , but can be found further north too , because it is a migratory species .

it is also present in most of africa and in asia , ranging to china and laos .

heliothis peltigera

valter jacinto marked
borboleta noturna / / bordered straw ( heliothis peltigera )
as trusted on the
heliothis peltigera
page .
valter jacinto marked
borboleta nocturna / / bordered straw ( heliothis peltigera )
as trusted on the
heliothis peltigera
page .
kari pihlaviita added the finnish common name
keltavaellusyökkönen
to
heliothis peltigera
.
bordered straw ( heliothis peltigera ) - norfolk moths - the macro and micro moths of norfolk .
histochemical localization of the pban receptor in the pheromone gland of heliothis peltigera . - pubmed - ncbi
hans - martin braun added the german common name
bilsenkraut - blüteneule
to
heliothis peltigera
.
observations on heliothis peltigera ( schiff . ) ( lep . , noctuidae ) and its natural enemies in anand ( gujarat state , india )
observations on heliothis peltigera ( schiff . ) ( lep . , noctuidae ) and its natural enemies in anand ( gujarat state , india ) | springerlink
patel rc ; patel jc ; patel jk , 1971 . new records of parasites of heliothis armigera ( hbn . ) and heliothis peltigera schiff . from gujarat . indian journal of entomology , 33 ( 2 ) : 223 - 224
danish records of h . peltigera . note that there are several corrections to litterature .
a . hispidum is an alternative host for a number of crop pests and diseases including : heliothis peltigera and h . armigera [ helicoverpa armigera ] ( lepidoptera : noctuidae ) (
the distribution , host - plants and natural enemies of h . peltigera in different countries is reviewed from literature records .
remarks : in europe , heliothis peltigera is native only in the mediterranean . but it migrates regularly in summer north to about southern scandinavia . the native distribution covers the subtropical and mediterranean regions of the old world ( africa , southern europe , asia ) .
the survey revealed that h . peltigera feeds primarily on a . hispidum and is not a serious pest of any economic plants in this region .
life cycle : heliothis peltigera has several generations during the year . i found caterpillars for example in the canaries quite common in winter and spring . the young larvae usually live in a webbed shelter mostly in the tip of the shoots , whereas the older ones can be observed resting openly on the plants .
manjunath tm ; patel rc ; yadav dn , 1976 . observations on heliothis peltigera ( schiff . ) ( lep . , noctuidae ) and its natural enemies in anand ( gujarat state , india ) . proceedings of the indian academy of sciences , b , 93 ( 2 ) : 55 - 65 .
the third part of the article describes the biology and distribution of peltigera . this is merely information from literature . important is the complete list of all records of peltigera from denmark . the list includes a number of hitherto unpublished danish records ( 9 findings ) and corrects some errors from the danish literature .
searched for natural enemies of a . hispidum in south america ( the centre of origin of this weed ) but concluded that there was little hope of finding effective biological control agents . heliothis peltigera is of some benefit in controlling a . hispidum in gujarat state , india but it can be a pest of economic plants (
heliothis virescens larvae were reared on a modified pinto bean diet [ 28 ] . eggs and larvae of both insect species were kept at 27 °c on a 16 h : 8 h l : d cycle .
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gaden s . robinson , phillip r . ackery , ian j . kitching , george w . beccaloni and luis m . hernández
hosts brings together an enormous body of information on what the world ' s butterfly and moth ( lepidoptera ) caterpillars eat . the web - based version presented here offers a synoptic data set drawn from about 180 , 000 records comprising taxonomically ' cleaned ' hostplant data for about 22 , 000 lepidoptera species drawn from about 1600 published and manuscript sources . it is not ( and cannot be ) exhaustive , but it is probably the best and most comprehensive compilation of hostplant data available .
we hope that it will be useful to a wide range of biologists and that it will act as a spur to further recording and analysis of caterpillar - plant interactions .
hosts can be searched in two ways , using text search and drill - down search modes .
in text search mode , use either lepidoptera or hostplant criteria or a combination of the two . hosts operates only using scientific names . it is not possible to search for the hostplants of the red admiral butterfly but a search for hostplants using its scientific name , vanessa atalanta , will be successful . enter the generic name ( vanessa ) in the - lepidoptera criteria - genus box ; enter atalanta in the species : box ; click search .
hint : leave the ' starts with ' command as the default and in the species entry box omit the last few letters of the species - name ( eg , atalant ) . this will get around the problem of variable gender - endings . hosts uses original orthography of species - group names as far as possible , but some checklists follow the convention of altering the species - group name to accord with the presumed gender of the generic name ( eg flava , flavus ) .
restrict or refine searches using additional criteria ; choosing ' usa ' from the drop - down location box and entering [ starts with ] ' urt ' in the hostplant family box will return hostplant records of vanessa atalanta from urticaceae in the usa .
hint : restricting location may deliver a very incomplete subset of records : in the previous example all records specified as from the nearctic region ( usa + canada ) would be missed .
leguminosae ( c ) - caesalpinioideae . leguminosae ( m ) - mimosoideae . leguminosae ( p ) - papilionoideae .
detailed published compilations from hosts are available in press . these books give greater detail than the website , together with comprehensive cross - indexes , record status and full bibliographies . they are indispensable tools for naturalists and professional entomologists .
robinson , g . s . , ackery , p . r . , kitching , i . j . , beccaloni , g . w . & hernández , l . m . 2001 . hostplants of the moth and butterfly caterpillars of the oriental region . 744 pp .
robinson , g . s . , ackery , p . r . , kitching , i . j . , beccaloni , g . w . & hernández , l . m . 2002 . hostplants of the moth and butterfly caterpillars of america north of mexico . 824 pp . [ memoirs of the american entomological institute , volume 69 . ]
beccaloni , g . w . , viloria , a . l . , hall , s . k . & robinson , g . s . 2008 . catalogue of the hostplants of the neotropical butterflies / catálogo de las plantas huésped de las mariposas neotropicales . m3m - monografías tercer milenio , volume 8 . zaragoza , spain : sociedad entomológica aragonesa ( sea ) / red iberoamericana de biogeografía y entomología sistemática ( ribes ) / ciencia y tecnología para el desarrollo ( cyted ) / natural history museum , london , u . k . ( nhm ) / instituto venezolano de investigaciones científicas , venezuela ( ivic ) . 1 - 536 pp . , 1 fig , 3 tabs .
gaden robinson was responsible for the overall project design and management of the hosts database , and for records of lepidoptera exclusive of butterflies and bombycoid moths . phillip ackery and george beccaloni were responsible for butterfly data , including data drawn from card catalogues developed by ackery , whilst ian kitching was responsible for hostplant data of bombycoid moths . luis m . hernández was responsible for abstracting in the latter two years of the project and for development of the bibliography for the hardcopy versions of the data .
we are extremely grateful to the many people who contributed their own rearing records of lepidoptera or personal accumulations of data for inclusion in the hosts database , particularly mike bigger ( uk ) , john w . brown ( usa ) , chris conlan ( usa ) , rob ferber ( usa ) , konrad fiedler ( germany ) , jeremy holloway ( uk ) , frank hsu ( usa ) , jurie intachat ( malaysia ) , alec mcclay ( canada ) , bill palmer ( australia ) , pierre plauzoles ( usa ) and the generous individuals who contributed rearing records through the worldwideweb and who are known to us only as an email address .
we are particularly grateful to julian donahue and the los angeles county museum of natural history for allowing us to include data on microlepidoptera from the card catalogue prepared by the late j . a . comstock and c . henne , and for access to manuscript records by noel mcfarland .
marian fricano ( santa clara university ) and aileen giovanello ( clark university , international internship 1996 ) made substantial contributions of abstracted data ; fran love ( north carolina ) painstakingly checked scanned texts and reformatted them for import to paradox .
we are indebted to all our helpers for their diligence , accuracy and patience , and for their unswerving faith that this daunting project would reach a conclusion .
we thank the trustees of the loke wan tho memorial foundation for their generous support for this project .
robinson , g . s . , p . r . ackery , i . j . kitching , g . w . beccaloni & l . m . hernández , 2010 . hosts - a database of the world ' s lepidopteran hostplants . natural history museum , london . urltoken . ( accessed : 18 aug . 2010 ) .
brummitt , r . k . 1992 . vascular plant families and genera . [ vi ] + 804 pp . , royal botanic gardens , kew .
kartesz , j . t . 1994 . a synonymized checklist of the vascular flora of the unites states , canada and greenland . timber press , portland . 1 , checklist , lxi + 622 pp ; 2 , thesaurus , vii + 816 pp .
kitching , i . j . & cadiou , j . - m . 2000 . hawkmoths of the world : an annotated and illustrated revsionary checklist . xx + 500 pp . , cornell university press , ithaca .
kitching , i . j . & rawlins , j . e . 1999 . the noctuoidea . pp . 355 - 401 . in : kristensen , n . p . ( ed . ) lepidoptera , moths and butterflies . 1 . evolution , systematics and biogeography . handbook of zoology , 4 ( 35 ) . lepidoptera . x + 491 pp . de gruyter , berlin .
letourneau , d . k . , hagen , j . a . & robinson , g . s . 2001 . bt crops : evaluating benefits under cultivation and risks from escaped transgenes in the wild . pp . 33 - 98 . in : letourneau , d . k . & burrows , b . e . ( eds ) , genetically engineered organisms : assessing environmental and human health effects . [ viii ] + 438 pp . , crc press , boca raton .
mabberley , d . j . 1987 . the plant book . a portable dictionary of the higher plants . xii + 707 pp . , cambridge university press . [ the 1993 reprint edition is currently used in editing . ]
nielsen , e . s . , edwards , e . d . & rangsi , t . v . ( eds ) 1996 . checklist of the lepidoptera of australia . monographs on australian lepidoptera . 4 . xiv + 529 pp . , csiro , melbourne .
nye , i . w . b . ( ed . ) 1975 - 91 . the generic names of moths of the world . 1 : 568 pp . ( noctuoidea ( part ) - nye , i . w . b . , 1975 ) ; 2 : xiv + 228 pp . ( noctuoidea ( part ) - watson , a . , fletcher , d . s . & nye , i . w . b . , 1980 ) ; 3 : xx + 243 pp . ( geometroidea - fletcher , d . s . , 1979 ) ; 4 : xiv + 192 pp . ( bombycoidea to zygaenoidea - fletcher , d . s . & nye , i . w . b . , 1982 ) ; 5 : xv + 185 pp . ( pyraloidea - fletcher , d . s . & nye , 1984 ) ; 6 : xxix + 368 pp . ( microlepidoptera - nye , i . w . b . & fletcher , d . s . , 1991 ) . british museum ( natural history ) / the natural history museum , london .
rawlins , j . e . 1984 . mycophagy in lepidoptera . pp . 382 - 483 . in : wheeler , q . & blackwell , m . ( eds ) fungus - insect relationships . perspectives in ecology and evolution . 514 pp . , columbia university press .
robinson , g . s . 1999 . hosts - a database of the hostplants of the world ' s lepidoptera . nota lepidopterologica , 22 : 35 - 47 .
robinson , g . s . , ackery , p . r . , kitching , i . j . , beccaloni , g . w . & hernández , l . m . 2001 . hostplants of the moth and butterfly caterpillars of the oriental region . 744 pp . southdene sdn bhd , kuala lumpur .
robinson , g . s . , ackery , p . r . , kitching , i . j . , beccaloni , g . w . & hernández , l . m . 2002 . hostplants of the moth and butterfly caterpillars of america north of mexico . memoirs of the american entomological institute , 69 : 1 - 824 .
scoble , m . j . ( ed . ) 1999 . a taxonomic catalogue to the geometridae of the world ( insecta : lepidoptera ) . 2 vols . csiro publications , melbourne .
royal botanic garden edinburgh dipterocarpaceae database : http : / / 193 . 62 . 154 . 38 / diptero /
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a migrant species , which varies in numbers from year to year , with large numbers in some years and absent in others . in a good migration year , larvae are often recorded , especially in southern coastal districts .
it is quite variable , and it is suggested that the paler individuals derive from desert origin , these often arriving with saharan ' dust storms ' .
june to august is the main arrival period , and southern england the most frequent location .
ukmoths is built , run and maintained by ian kimber , with thanks to the many kind contributors who provide photos and information .
the ukmoths facebook page is a great place to post your identification queries . more often than not you ' ll get a positive id on most photos fairly quickly .
looking for a specific moth species ? enter just part of the name below .
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host plants : the larvae are polyphagous . i found caterpillars in greece on achillea and in the canaries on pelargonium , nicotiana , lotus and various asteraceae such as calendula or dittrichia viscosa . apparently preferred are solanaceae , asteraceae and fabaceae .
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all photos included on this page can only be used for educational purposes . for publication in journals , books or magazines , permission should be obtained from the original photographers with a copy to eppo .
european union funding : for a one - year period ( 2017 - 12 - 16 to 2018 - 12 - 15 ) , eppo has been awarded an eu grant for the further development of the eppo code system ( agreement nb : sante / 2017 / gs / eppo / s12 . 768842 ) . the eu commission is not responsible for any use that may be made of the information from this project subsequently included in the eppo global database .
comes to light at night , also can be seen flying by day in warm sunshine , visiting flowers .
recorded in 40 ( 58 % ) of 69 10k squares . first recorded in 1884 . last recorded in 2018 .
underlying maps using digital map data © norfolk online lepidoptera archive - nola™ 2018 . © james wheeler - n o r f o l k m o t h s 2007 - 2018 . data © nola™ 2018
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altstein m 1 , ben - aziz o , bhargava k , li q , martins - green m .
department of entomology , the volcani center , bet dagan 50250 , israel . vinnie2 @ urltoken
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a widespread but rare immigrant in belgium . numbers vary much over the years .
the adults have been recorded from may till early october . they can be seen during the day visiting flowers . they come to light .
our previous blog post looked at preparing the lepidoptera for digitisation . in this post , we will look at the second part of the digitisation process ; the imaging and transcription that allows data to be set free and accessed by the global science audience on the museum’s data portal .
let’s find out what’s involved and why it’s leading to new ways of accessing and using the information in our collections .
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a . hispidum is a troublesome annual weed of annual and perennial crops , which has spread remarkably widely from its origins in south america , almost exclusively as a result of accidental rather than deliberate transfer . the spiny fruits are a particu . . .
a . hispidum is a troublesome annual weed of annual and perennial crops , which has spread remarkably widely from its origins in south america , almost exclusively as a result of accidental rather than deliberate transfer . the spiny fruits are a particular hazard to livestock and assist the movement of the weed in agricultural produce . there are many countries , and regions within larger countries , to which it could yet be introduced and prove invasive , with corresponding costs to agriculture .
the distribution in this summary table is based on all the information available . when several references are cited , they may give conflicting information on the status . further details may be available for individual references in the distribution table details section which can be selected by going to generate report .
) . in each case there was some lag before it became invasive , but in india this was apparent by the 1940 ' s . in australia it was naturalized by 1906 and then spread steadily . the origin and means of introduction are generally unknown , but in florida and at other points along the eastern usa , it is believed to have been introduced in ship ballast (
) and in most other areas it is assumed to have come in accidentally , as a crop seed contaminant , or adhering to imported wool , skins and furs , rather than deliberately . in southern india , it was first noted around railway stations , and it seems clear that railways have been an important means of spread within countries .
a . hispidum is listed as a prohibited or restricted species for the states of western australia and northern territories in australia , and for hawaii , usa .
a . hispidum is a common weed of arable land , pastures , roadsides and wasteland . it grows in a wide range of climatic conditions and soil types ( particularly light soils ) . it appears to behave similarly in both native and invaded areas . it is mainly tropical and sub - tropical in distribution , but occurs up to altitudes of 1700 m in east africa (
) infesting small - and large - grained cereals , legumes , tree crops ( citrus , peach , rubber , vines ) , vegetables and oil seeds . most crops are likely to be infested with a . hispidum when grown within the habitat range of this weed .
) . after burial for one year , 80 % of seed remains viable . freshly harvested seed has 36 % germination , dropping to 15 % after dry storage for one year (
- citing the work of p thomas in zimbabwe during 1975 - 82 ) . most seeds of a . hispidum emerge within three years of production and all seeds die within eight years whether the field is cultivated or not (
) . garcia and sharif ( 1995a , b ) showed that seeds were generally dormant immediately after being collected . the achenes responded positively to light , and germination was equally promoted by red and far - red light . the germination was highest in the temperature range 20 - 25°c . seeds also responded to scarification .
seedlings emerge over an extended period in the presence of adequate soil moisture and when temperatures are high enough ( 20 - 30°c ) . subsequent growth is rapid , the first fruit appearing 35 - 40 days after emergence , seed maturation occurring 45 - 50 days later (
biomass and seed production are reduced when a . hispidum grows in the shade . this probably accounts for its reduced competitiveness in mixed cropping systems compared with crop monocultures (
a . hispidum is monoecious , having male flowers in the centre and female flowers on the outside of the inflorescence . self - pollination and cross - pollination occur by wind . the spiny achenes ( burrs ) are readily dispersed on the wool and fur of animals and through contamination of hay and crop residues . they are also carried considerable distances by streams and floodwaters .
a . hispidum apparently requires a certain minimum warmth to germinate and thrive . in south africa it occurs in the summer rainfall areas but not so much where there is a mediterranean climate with winter rainfall . it would presumably be susceptible to frost , but , as an annual , it can occur in temperate areas with very low minimum temperatures , as the summer temperatures , even in e . g . northeast russia , can regularly exceed 20°c .
a . hispidum is especially common on very light sandy soils , but is by no means restricted to this soil type , occurring as a serious weed on a wide range of soils , including clays .
a . hispidum is an alternative host for several crop pests , see the section on economic impact for further details .
) . it is a declared noxious weed in hawaii , usa and australia . the quality of sheep wool is reduced when contaminated by the spiny achenes , and livestock are harmed when the achenes penetrate the hooves , often resulting in infection and subsequent lameness . the plant is toxic to animals when consumed on a daily basis , but is generally avoided by livestock (
crop yields are decreased in the presence of a . hispidum which competes for water , nutrients and light .
illustrated a negative linear relationship between groundnut seed yield and the period of interference from a . hispidum . each week of interference reduced seed yields by 20 , 205 and 134 kg / ha , respectively , over three consecutive years , and as little as two weeks of interference caused significant seed yield reductions . full - season interference from 8 and 64 a . hispidum plants per 7 . 5 m of crop row reduced groundnut seed yields by 14 % and 50 % , respectively .
recorded losses in soyabean due to a . hispidum planted in pots the same day , but no loss when the weed was planted after 11 or 22 days . congo ,
studied different ratios of soyabean and a . hispidum at a range of densities and concluded that the two species share the same resources without antagonistic interactions .
note that this is a c3 plant with relatively inefficient photosynthesis but that its competitive effect may be enhance by allelopathic influence . crop losses are also caused by interference from a . hispidum at harvest time . this is a major cause of soyabean yield losses in brazil (
a . hispidum appears to occur relatively rarely in undisturbed habitats , and has not been reported to have an undesirable impact on natural vegetation .
a . hispidum is not known to have invaded national parks or other protected areas beyond occurrence as a weed of already disturbed ground , e . g . along roadsides .
the spiny fruits of this weed can cause pain and injury to man and animals , and there are some concerns about toxicity to livestock , but there are no reports of serious impact on tourism or other human activities .
) . various tribes in west africa use a . hispidum for the treatment of arthritis , leprosy , migraine , rheumatism and stomach complaints (
refer to the use of a . hsipidum as a traditional treatment for infectious diseases in benin and show that , in the porcine immune system , a . hispidum enhances the proliferation of t lymphocytes .
also showed inhibitory activity of a . hispidum extracts on several herpes and pseudo - rabies viruses .
acanthospermum australe is a prostrate , glandular herb , similar to a . hispidum but softly tomentose on all parts .
acanthospermum glabratum is a trailing , annual herb , uncommon in kenya in the 1970s but becoming quite a common weed in central kenya by 1990 ( pj terry , long ashton research station , university of bristol , personal communication , 1998 ) .
quarantine must be considered an integral part of any control programme . all animals brought onto a farm , as well as those transferred from infested to burr - free parts of the farm , must be checked and any burrs removed (
) , so that prevention of seeding will eventually exhaust the soil seedbank and eradicate the weed . seedbank depletion can be achieved by ploughing to bury existing seeds to a depth of at least 10 cm , followed by the sowing of an appropriate perennial pasture . any seedlings which emerge in the pasture should be removed by pulling , hoeing or with herbicides (
herbicides that are reputed to give control of a . hispidum include : 2 , 4 - d , diolamine , acetochlor , atrazine , bentazon , butachlor , cyanazine , diuron , fluometuron , imazethapyr , lactofen , linuron , mefluidide , metolachlor , napropamide , oxyfluorfen , paraquat , pendimathalin , simazine and terbutryn . pendimethalin is reported to be selective against a . hispidum in groundnut (
found a . hispidum to be less susceptible than other broad - leaved weeds to pendimethalin , fluchloralin and metolachlor in field bean . a . hispidum was shown by
indicate promising selectivity in soyabean for the new herbicides carfentrazone and carfentrazone - ester .
adams cd , 1963 . compositae . in : hutchinson j , dalziel jm , hepper fn , eds . flora of west tropical africa , volume 2 , second edition . london , uk : crown agents .
ballais c , 1969 . plants adventices de la gironde . toulouse , france : monde plantes , 365 : 5 - 9 .
banda ea ; morris b , 1986 . common weeds of malawi . lilongwe , malawi : the university of malawi .
berhaut j , 1967 . flore du senegal . dakar , senegal : editions clairafrique .
bhattacharyya g ; pandya sm , 1996 . distribution studies on exotic weeds of saurashtra ( india ) . advances in plant sciences , 9 : 29 - 32 .
blundell m , 1992 . wild flowers of east africa . london , uk : harper collins .
buch tg ; shvydkaya vd , 1989 . new and rare adventitious species for the soviet flora and primorye territory . botanicheskii zhurnal , 74 ( 10 ) : 1512 - 1517 .
burkhill hm , 1985 . the useful plants of west tropical africa . vol . i . families a - d . kew , uk : royal botanic gardens .
chakravarti s , 1963 . weed control in india . indian agriculturalist , 7 : 23 - 58 .
chivinge oa , 1990 . the interaction of soyabean ( glycine max ( l . ) merill ) and upright starbur ( acanthospermum hispidum ) . zimbabwe journal of agricultural research , 28 ( 1 ) : 71 - 74
davis g ; voll e ; lorenzi h ; chehata a , 1979 . soybean yield response to control of brachiaria plantaginea and acanthospermum hispidum . proceedings of the 32nd annual meeting of the southern weed science society . , 333
drummond rb , 1984 . arable weeds of zimbabwe . harare , zimbabwe : agricultural research trust of zimbabwe .
foloni ll ; christoffoleti pj , 1999 . chemical weed control in soybean in brazil using new herbicides and mixtures . 1999 brighton crop protection conference : weeds . proceedings of an international conference , brighton , uk , 15 - 18 november 1999 . , volume 1 : 315 - 318 ; 3 ref .
fournet j ; hammerton jl , 1991 . weeds of the lesser antilles . paris , france : department d ' economie et sociologie rurales , institut national de la recherche agronomique .
garcia qs ; sharif rr , 1995 . ecophysiological aspects of dormancy break in acanthospermum hispidum dc . revista brasileira de botanica , 18 ( 1 ) : 113 - 117
garcia qs ; sharif rr , 1995 . germination and dormancy in achenes of acanthospermum hispidum dc , a weed species . revista brasileira de botanica , 18 ( 1 ) : 17 - 25
gonzalez g ; webb me , 1989 . manual para la identificacion y control de malezas . santa cruz , bolivia : centro internacional de agricultura tropical .
gowda rc ; devi ls ; prasad tvr , 2002 . bio - efficacy of herbicides in groundnut and residues of pendimethalin in soil under fingermillet - groundnut cropping system . pesticide research journal , 14 ( 2 ) : 263 - 267 ; 5 ref .
hall dw ; vandiver vv , 1991 . bristly starbur , acanthospermum hispidum dc . sp37 . florida , usa : florida cooperative extension service , institute of food and agricultural sciences , university of florida .
henderson m ; anderson jg , 1966 . common weeds in south africa . south africa : department of agricultural and technical services .
holm l ; doll j ; holm e ; pancho j ; herberger j , 1997 . world weeds . natural histories and distribution . new york , usa : john wiley and sons , inc .
holm lg ; pancho jv ; herberger jp ; plucknett dl , 1979 . a geographical atlas of world weeds . new york , usa : john wiley and sons , 391 pp .
jurgens g , 1977 . list of weeds of agricultural crops in the dominican republic . berichte aus dem fachgebiet herbologie der universitat hohenheim , heft 12 : 102 pp .
kostermans ajgh ; wirjahardja s ; dekker rj , 1987 . the weeds : description , ecology and control . weeds of rice in indonesia [ edited by soerjani , m . ; kostermans , a . j . g . h . ; tjitrosoepomo , g . ] jakarta , indonesia ; balai pustaka , 24 - 565
lloyd d , 1956 . remarks on the possible biological control programme with the weed acanthospermum hispidum dc . canadian entomologist , 88 : 613 - 622 .
lorenzi h , 1982 . weeds of brazil , terrestrial and aquatic , parasitic , poisonous and medicinal . ( plantas daninhas de brasil , terrestres , aquaticas , parasitas , toxicas e medicinais . ) nova odessa , brazil : h . lorenzi , 425 pp .
lorenzi hj ; jeffery ls ( editors ) , 1987 . weeds of the united states and their control . new york , usa ; van nostrand reinhold co . ltd . , 355 pp .
luo xiaoyong ; matsumoto h , 2002 . susceptibility of a broad - leaved weed , acanthospermum hispidum , to the grass herbicide fluazifop - butyl . weed biology and management , 2 : 98 - 103 .
mariappan v ; narayanasamy p , 1972 . acanthospermum hispidum dc . , a new host of tomato leaf curl virus . madras agricultural journal , 59 : 355 - 357 .
mariappan v ; narayanasamy p , 1977 . characterisation of viruses affecting weeds - 1 . mosaic diseases . madras agricultural journal , 64 ( 2 ) : 106 - 112 .
marzocca a , 1979 . manual de malezas . 3rd edition . buenos aires , argentina : editorial hemisferio sur .
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understanding the life cycle and behaviour of helicoverpa improves our ability to identify weak points in the pest ' s biology and ecology and manage it more sustainably . life cycles of h . armigera and h . punctigera take 4 - 6 weeks from egg to adult in summer , and 8 - 12 weeks in spring or autumn .
fertile eggs hatch in about three days during warm weather ( 25°c average ) and 6 - 10 days in cooler conditions , changing from white to brown to a black - head stage before producing a hatchling . not all eggs are fertile . physical factors can dramatically affect egg survival and larval establishment . heavy rainfall and wind can force eggs off leaves . high temperatures can dehydrate and kill eggs and very small larvae .
the hatching larva ( neonate ) eats through the eggshell to make an exit hole . neonate larvae are 1 - 1 . 5 mm long , with a brown - black head and white or yellowish - white , dark - spotted body .
larvae develop through six growth stages ( instars ) and become fully grown in 2 - 3 weeks in summer or 4 - 6 weeks in spring or autumn . development is more rapid at higher temperatures , up to 38°c , after which development slows . larval activity and feeding stops when temperatures fall below 12°c . fully grown sixth instar larvae are 40 - 50 mm long and there may be considerable variation in colours and markings .
it is important to note that 90 % of all feeding ( and therefore damage ) is done by larva from the third instar ( 8 - 13 mm long ) onwards . large larvae ( longer than 24 mm ) are the most damaging stage , since larvae consume about 50 % of their overall diet in the fifth and sixth instars . larvae need to be targeted when they are still small ( less than 7 mm ) .
larvae feed on leaves , flower buds and flowers , developing pods , fruits and seeds . in most crops , young larvae will graze on leaves alone , moving on to feeding on developing pods , bolls , cobs and grain once they are third instar or older ( 8 mm or longer ) . in some crops , such as mungbeans and cotton , larvae infest reproductive structures ( flowers , squares ) as soon as they hatch . once established in these concealed feeding locations , larvae are much more difficult to control with insecticides .
helicoverpa punctigera prefers broadleaf species ( e . g . cotton , chickpea , native herbs ) ; h . armigera will attack these crops and grass - related species ( e . g . maize , sorghum and wheat ) . crop and pasture weeds such as noogoora burr , common sowthistle , fat hen and marshmallow are also hosts .
in southern queensland , pupae typically start to go into diapause from around mid - march and emerge in spring . not all pupae that form in late summer go into diapause : a proportion continues to develop , perhaps emerging during winter , or early in spring .
overwintering pupae are susceptible to soil disturbance and disruption of the emergence tunnel . cultivation to 10 cm is enough to create this disturbance .
adult moth wingspan is 30 - 45 mm . the forewings are brownish or reddish - brown ( females ) or dull greenish to yellow or light brown ( males ) . hindwings are pale with a broad , dark outer margin . h . armigera moths have a pale patch near the centre of this dark region .
moths feed on nectar and live for around 10 days . females lay around 1000 eggs in singles or clusters on growing points , leaves , flower buds , flowers and developing fruits , and sometimes on stems . moths tend to lay eggs on the top third of healthy plants and on vigorously growing terminals .
although both species of helcoverpa are capable of travelling hundreds of kilometres on high altitude winds , this characteristic is more typical of h . punctigera , which breeds during winter on flowering plants in inland australia , migrating when this vegetation dies off in late winter / spring . the moths reach the eastern cropping areas by flying on the warm winds that precede cold fronts in spring , making h . punctigera an early season pest . the likely magnitude of these influxes can be estimated by monitoring the breeding areas in inland australia during winter .
most h . armigera spring moths come from local populations that survive from year to year .
from southern queensland south , the majority of h . armigera moths overwinter as pupae . after one or two generations in spring and early summer , h . armigera numbers increase to become the dominant species in mid - summer to autumn .
from central queensland north , winter temperatures are warm enough for pupae not to enter diapause , and these regions experience year - round helicoverpa activity .
pheromone ( chemical lure ) traps attract male moths using the sex pheromone that female moths emit to attract mates . h . armigera and h . punctigera pheromones are different , so each species can be monitored separately .
a diapause and emergence computer model ( available on the cottassist website ) uses current local temperatures to calculate the rate of development of pupae in the soil , and predicts the timing of emergence of moths . this model can also be used to predict the beginning of diapause of h . armigera , which can then be used to identify at - risk fields for pupae busting in any given year .
& copy ; the state of queensland ( department of agriculture and fisheries ) 2010–2018 . queensland government
. this is particularly true in agricultural ecosystems , where anthropogenic selection pressure is strong .
primarily feeds on cotton in its larval stages , and us populations have been declining since the widespread planting of transgenic cotton , which endogenously expresses proteins derived from bacillus thuringiensis ( bt ) . no physiological adaptation to bt toxin has been found in the field , so adaptation in this altered environment could involve ( i ) shifts in host plant selection mechanisms to avoid cotton , ( ii ) changes in detoxification mechanisms required for cotton - feeding vs . feeding on other hosts or ( iii ) loss of resistance to previously used management practices including insecticides . here , we begin to address whether such changes occurred in h . â
populations between 1997 and 2012 , as bt - cotton cultivation spread through the agricultural landscape . for our study , we produced an h . â
genome assembly and used this in concert with a ddrad - seq - enabled genome scan to identify loci with significant allele frequency changes over the 15 - year period . genetic changes at a previously described h . â
insecticide target of selection were detectable in our genome scan and increased our confidence in this methodology . additional loci were also detected as being under selection , and we quantified the selection strength required to elicit observed allele frequency changes at each locus . potential contributions of genes near loci under selection to adaptive phenotypes in the h . â
have relatively simple structures consisting of a hydrocarbon chain with a functional group and one to several double bonds . these sex pheromones are derived from fatty acids through specific biosynthetic pathways . we investigated the incorporation of deuterium - labeled tetradecanoic , hexadecanoic , and octadecanoic acid precursors into pheromone components of
utilize ( z ) 11 - hexadecenal as the major pheromone component , which is produced by delta11 desaturation of hexadecanoic acid . h . subflexa also produced ( z ) 11 - hexadecanol and ( z ) - 11 - hexadecenyl acetate via delta11 desaturation . in h . subflexa , octadecanoic acid was used to biosynthesize the minor pheromone components ( z ) 9 - hexadecenal , ( z ) 9 - hexadecenol , and ( z ) 9 - hexadecenyl acetate . these minor components are produced by delta11 desaturation of octadecanoic acid followed by one round of chain - shortening . in contrast , h .
used hexadecanoic acid as a substrate to form ( z ) 11 - hexadecenal and ( z ) 11 - hexadecenol and hexadecenal . h .
also produced ( z ) 9 - tetradecenal by delta11 desaturation of the hexadecanoic acid followed by one round of chain - shortening and reduction . tetradecanoic acid was not utilized as a precursor to form z9 - 14 : ald in h .
( lepidoptera : noctuidae ) were shown to transfer 36 % of a whole body / sup 65 / zn burden to the females at the time of mating . approximately 5 % of the male ' s and 11 % of the female ' s total / sup 65 / zn burdens were found in eggs oviposited during a 10 - day period following mating . transfer of zinc at mating by
males may represent the conservation of an essential trace element that must be retained throughout the life cycle .
that were challenged with helicoverpa zea single nucleopolyhedrovirus ( hzsnpv ) . a reference transcriptome of hemocyte - expressed transcri . . .
ascoviruses ( avs ) infect larvae of various insect pests belonging to the family noctuidae . the result of av infection in the hosts is cleavage of infected cells into vesicles , a unique feature of av infection . since insect cell lines facilitate the study of virus life cycles , attempts were made to analyze
av ( hvav3e ) infection in several cell lines and compare cell pathology to larval infection . in this study , replication and cytopathological effects of hvav3e on four different cell lines were investigated . hvav3e replication was confirmed in three noctuid cell lines from spodoptera frugiperda ( sf9 ) and helicoverpa zea ( bcirl - hz - am1 and fb33 ) . however , the virus did not replicate in the non - noctuid insect cell line from pieris rapae ( pieridae ) . despite replication of the virus in the three permissive cell lines , the cytopathological effects of the virus were significantly different from that of larval infection .
population genetic studies are essential to the better application of pest management strategies , including the monitoring of the evolution of resistance to insecticides and genetically modified plants . bt - crops have been instrumental in controlling
following baculovirus infection . fe concentrations were determined by icp - ms in hemolymph collected from 4th instar larvae infect . . .
staudacher , heike ; kaltenpoth , martin ; breeuwer , johannes a . j . ; menken , steph b . j . ; heckel , david g . ; groot , astrid t .
microbes associated with insects can confer a wide range of ecologically relevant benefits to their hosts . since insect - associated bacteria often increase the nutritive value of their hosts ' diets , the study of bacterial communities is especially interesting in
that are important agricultural pests . we investigated the composition of bacterial communities in the noctuid moth
, helicoverpa zea , and helicoverpa armigera . partial nucleotide sequencing and phylogenetic analysis of three highly conserved genes . . .
. the available evidence indicates that this detoxification mechanism is part of larval constitutive metabolism and not induced in response to canavanine . h .
larvae , administered 5 mg / g l - canavanine supplemented with 37 . 7 kbq l - ( guanidinooxy - { sup 14 } c ) canavanine , were sacrificied 0 , 1 , 2 , 4 , 6 , and 12 h postinjection . the principle products of l - canavanine degradation were ( { sup 14 } c ) guanidine and ( { sup 14 } c ) urea . homoserine formation was confirmed by automated amino acid analysis . this study demonstrates that the principal detoxificationmoreâ â» pathway for l - canavanine in h .
that have been reported in australia , indonesia , china , and the united states . to understand the diversity and origin of this important ascovirus , the complete genome of the hvav indonesia strain ( hvav - 3g ) , isolated from spodoptera exigua , was determined to be 199 , 721 bp , with a g + c content of 45 . 9 % . therefore , hvav - 3g has the largest genome among the reported ascovirus genomes to date . there are 194 predicted open reading frames ( orfs ) encoding proteins of 50 or more amino acid residues . in comparison to hvav - 3e reported from australia , hvav - 3g has all the orfs in hvav - 3e with 6 additional orfs unique to hvav - 3g , including 1 peptidase c26 gene with the highest identity to drosophila spp . and 2 gas vesicle protein u ( gvpu ) genes with identities to bacillus megaterium . the five unique homologous regions ( hrs ) and 25 baculovirus repeat orfs ( bro ) of hvav - 3g are highly variable .
enriched for simple sequence repeats ( ssr ) and nucleotide sequences of expressed sequence tags ( est ) . nucleotide sequences of 192 clones from the partial genomic library yielded 147 u . . .
post - embryonic development and molting in insects are regulated by endocrine changes , including prothoracicotropic hormone ( ptth ) - stimulated ecdysone secretion by the prothoracic glands ( pgs ) . in lepidoptera , two pathways are potentially involved in ptth - stimulated ecdysteroidogenesis , mitogen - activated protein kinase ( mapk ) and phosphoinositide 3 - kinase / protein kinase b / target of rapamycin ( pi3k / akt / tor ) . we investigated the potential roles of both these pathways in
last instar larvae , both pathways modulated ptth - stimulated ecdysteroidogenesis . finally , we analyzed the post - embryonic development of third and fourth instar larvae fed on diet supplemented with rapamycin , in order to better understand the role of the tor pathway in larval growth . when rapamycin was added to the diet of larvae , the onset of molting was delayed , the growth rate was reduced and abnormally small larvae / pupae with high mortality rates resulted . in larvae fed on diet supplemented with rapamycin , the growth of pgs was suppressed , and ecdysone production and secretion were inhibited . overall , the in vivo and in vitro results demonstrated that , similarly to bombyx mori , mapk and pi3k / akt / tor pathways are involved in ptth signaling - stimulated ecdysteroidogenesis , and indicated the important role of tor protein in h .


lytoceratidae is a taxonomic family of ammonoid cephalopods belonging to the suborder lytoceratina , characterized by very evolute shells that generally enlarge rapidly , having whorls in contact but mostly overlapping very sightly , or not at all .

surface ornament may consist of various combinations of straight or crinkled growth lines , flares , constrictions , and , more rarely , plications .

sutures are highly complex and moss-like , but with few major elements .

lateral lobes are widely splayed and blunt , or with obliquely deflected end .

the external , ventral , lobe is short .

the lytoceratinae have a worldwide distribution and a stratigraphic range extending from the middle lower jurassic ( pliensbachian ) to the early upper cretaceous ( cenomanian ) .

lytoceratidae

subject phylloceratidae > france > lyon region . lytoceratidae > france > lyon region . paleontology > jurassic . animals , fossil > france > lyon region .
the heteromorphic ammonite genus pictetia has previously been included in the lytoceratidae . a reassessment of literature data and a detailed analysis of the suture shows that pictetia lacks a septal lobe as well as a bifid internal lobe and lateral lobe , all features indicative of the lytoceratidae . this and the quadrilobate suture line , combined with the loose coiling of the shell , indicate that it should be included in the polyphyletic suborder “ancyloceratina” . any further systematic assessment is impossible at the moment . bisher wurde die heteromorphe ammonitengattung pictetia zu den lytoceratidae gestellt . die auswertung von literaturdaten sowie genaue untersuchungen der suturlinie zeigen , dass die charakteristischen merkmale der lytoceratidae , wie der septallobus , ein bifider intern - und laterallobus , bei pictetia nicht ausgebildet sind . dies und die quadrilobate suturlinie sowie das lose aufgewundene gehäuse erfordern eine systematische zuordnung zur polyphyletischen gruppe der „ancyloceratina” . eine nähere taxonomische einordnung ist zur zeit nicht möglich .
in the yorkshire lias another relatively rare family of ammonites is the lytoceratidae – finding a lytoceras always makes a day a great collection day , the evolute shell shape reminiscent of a “horn of plenty” and the complex suture make the ammonites very appealing .
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see also alsen 2006 , arkadiev et al . 2000 , förster 1975 , förster and weier 1983 , geczy and meister 2007 , hillebrandt 2006 , hoffmann and keupp 2010 , landra et al . 2000 , venturi et al . 2005 , wiedmann 1970 , wiedmann 1979 and wright et al . 1996
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responsibility louis rulleau . language french . abstract in english . imprint villeurbanne : u . f . r . des sciences de la terre , université claude bernard - lyon i , [ 1998 ] physical description 166 p . : ill . ; 30 cm . series documents des laboratoires de géologie ; no 149 .
it gathers together ammonites with circular , oval or subquadratic section and episodical constrictions . they are characterized by a fine and dense costulation and their venter is sometimes keeled . their stratigraphic distribution spreads out from the sinemurian up to the cretaceous . however , it seems to be very rare in the jurassic layers of the cher and nièvre .
it is rather uncommon in the bathonian deposits of southern paris basin , on the contrary to southern france . only one species has been recognized : nannolytoceras tripartitum ( stur . ) . it is an evolute ammonite with several deep constrictions .
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, with [ a ] tendency to uncoil . [ the ] suture is more or less as in
[ la ] famille des macroscaphitidae [ comprend ] deux genres principaux , probablement voisins ( . . . )
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it gathers together shells with circular , oval or subquadratic section and episodical constrictions . they are ammonites characterized by a fine and dense costulation , sometimes crenulated . their stratigraphic distribution spreads out from the sinemurian up to the cretaceous period .
the whole pliensbachian layers of eastern berry , carixian and domerian taken together , contain only two species .
it groups together forms with circular , oval or square sections and episodic constrictions . they are evolute ammonites with fine , dense and sometimes crenulated ribbing .
meister 1986 , wrote about a possible sexual dimorphism lytoceras - derolytoceras . the last one seems to have in fact , all the characteristics of a microconch . it is a small form with circular whorls . the phragmocone is covered with fine , dense and crenulated ribs which thicken on the bodychamber .
it gathers together shells with circular , oval or subquadratic section and episodical constrictions . the ammonites are characterized by a fine and dense costulation , sometimes crenellated . their stratigraphic distribution spreads out from the sinemurian up to the cretaceous period .
it groups together forms with circular , oval or square sections and episodic constrictions . the ammonites are evolute with fine , dense and sometimes crenellated ribbing .
meister 1986 , wrote about a possible sexual dimorphism lytoceras - derolytoceras . the last one seems to have in fact , all the characteristics of a microconch . it is a small form with circular whorlshape . the phragmocone is covered with fine , dense and crenellated ribs which thicken on the bodychamber .
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) and other , later , authors ( e . g . kennedy and klinger
showed that the development of l ( triﬁd vs . biﬁd ) can by no
kennedy and klinger : 326 , ﬁg . 50 , 327 , ﬁg . 51 .
nedy in fischer and gauthier : 139 , pl . 40 , ﬁg . 5a–c .
whorl breadth of 23 mm at a diameter of about 35 . 5 mm .
the dfg ( ke 322 / 32 - 1 ) . we thank m . bulang - lo
suture line drawings and j . evers ( fu berlin ) for photographic works .
we are grateful to c . klug and h . furrer ( eth zurich ) for providing
referees p . bengtson ( heidelberg ) and j . lehmann ( bremen ) for their
o . h . schindewolf , p . c . sylvester - brady , and c . w . wright .
davis , r . a . , n . h . landman , j . l . dommergues , d . marchand , and h .
man , k . tanabe , and r . a . davis , 463–539 . new york and
] , ed . n . p . luppov and v . v . drus
russian ] ; english edition : n . p . luppov and v . v . drushchits ,
academy of sciences of the u . s . s . r . , earth sciences section
llmi , k . b . 1989b . evolution of the mid - cretaceous triad .
haug , e . 1900 . review of textbook of palaeontology by k . von
zittel , translated by ch . eastman ( cephalopoda by a . hyatt ) .
, ed . j . - c . fischer , and h . gauthier , 139 . leiden :
cke , and d . s . wray . 2000 . integrated stratigraphy across the
, ed . a . taira , and m . tashiro , 283–298 . kochi :
meister , c . 1986 . les ammonites du carixien des causses ( france ) .
price , f . g . h . 1874 . on the gault of folkestone .
spath , l . f . 1923 . a monograph of the ammonoidea of the gault . part
spath , l . f . 1939 . a monograph of the ammonoidea of the gault . part
wright , c . w . , j . h . callomon , and m . k . howarth . 1996 . part l
. . . according to arkell ( 1957 ) , variation is the greatest among regressive types in which the suture line is secondarily simplified ( e . g . , in jurassic and cretaceous
pseudoceratites
) . the suture line is also quite variable in several mesozoic heteromorphs and might therefore be of little help for taxonomy ( kakabadze 2004 ) , particularly at lower taxonomic levels ( e . g . , hoffmann et al . 2009 ) . differences in suture line between specimens of the same species at a similar diameter have been related to differences in whorl shape ( e . g . , arkell 1957 ; reeside and cobban 1960 ) , ornamentation ( e . g . , casey 1961 ; westermann 1966 ) and / or ontogenetic development ( e . g . , hammer and bucher 2006 ) , but they might also be more random ( e . g . , no clear correlation with other properties of the shell or ontogeny ) . . . .
. . . in ammonites , this holistic approach was considered for the heteromorph acanthoscaphites tridens ( kin 2010 ) . deshayesites belongs to the recoiled heteromorphic ammonites , and although heteromorphs are regarded as a polyphyletic group ( hoffmann et al . 2009 ) , a particularly wide range of variation appears to be characteristic ( kakabadze 2004 ) . additionally , environmental pressure can result from further ecological constraints , including changes in oxygen levels as well as the warming trend with the subsequent invasion of tethyan species . . . .
. . . 8 ) . the high stability of nautilus ( s t % 0 . 09 ) is due to its extremely short body - chamber and high w , which among mesozoic ammonoids is probably matched only by some lytoceratines and exceptional ancyloceratines , e . g . , scaphitidae ( landman et al . , 2010 ) or pictetia ( hoffmann et al . , 2009 ) . short body - chambers and / or high w are more frequent in palaeozoic ammonoids ( e . g . , klug , 2001 ) . . . .
. . . comparison : the depressed whorl section , smooth internal mould of gsub c1667 is comparable to that of p . depressa ( pictet & campiche , 1861 ) . however , the kidneylike whorl section typical of p . depressa , the well - developed depression of the dorsal zone ( hoffmann et al . 2009 ) as well as details of the suture line can only be assumed in the material available . furthermore , the whorl expansion is another critical feature that cannot be seen in the poorly preserved fragment . . . .
. . . is a rare species as already mentioned by spath ( 1923 ) and this explains why gsub c1667 and c6022 are the only specimens that can be possibly referred to this taxon among several hundreds of ammonites from erratic boulders in the hohendorf district . we follow hoffmann et al . ( 2009 ) in questioning the supra - generic classification of pictetia as a lytoceratid in the treatise ( wright et al . 1996 ) . pictetia has no septal lobe as well as no bifid internal and lateral lobes , but possesses a quadrilobate suture line that is characteristic of ancyloceratids . . . .
i ' m interested in ( body - and trace - ) fossils especially from campanian and maastrichtian of nw - europe . i study the interaction of various organisms to get an idea of the palaeoecological system in …
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renewed interest in an old hobby . currently working on a paper on the lytoceratids from the lowermost toarcian together with rené hoffmann ( bochum ) . hoping to do more work with him and günter schwe…
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heritable phenotypic variation is usually thought to be the raw material for evolution and natural selection . knowledge of the intraspecific variability of any taxon is therefore essential for syst…
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it is well - known that konservät - lagerstätten can provide important constraints on the paleobiology , soft - tissue anatomy and ecology of benthic organisms . however , many lagerstätten also provide imp…
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here , we describe for the first time the occurrence of well preserved pictetia from the albian of northeastern japan ( miyako group ) and discuss the implications for the systematic assignment of the genus . a detailed systematic description of p . astieriana based on the newly collected material is given . earlier systematic assignment to lytoceratids resulted from similar conch morphology and . . . [ show full abstract ]
we herein review fossil examples of pathological phenomena and present a historical review , definition , and the taxonomic handling of such anomalies ( forma aegra concept , symptom vs . syndrome ) . the described phenomena are separated in those with exogenic ( injuries , epizoans ) or endogenic reasons ( parasitoses , physiological disturbations ) . sublethal injuries allow in some cases to identify the . . . [ show full abstract ]
additional prionocyclus germari ( reuss , 1845 ) ( cretaceous ammonoidea , upper turonian ) from nw german . . .
abstract the pliensbachian and toarcian ( early jurassic ) ages are characterised by several , relat . . .
worldwide inventarisation of all known lower cretaceous phylloceratid , lytoceratid , haploceratid . . .
worldwide inventarisation of all known lower cretaceous phylloceratid , lytoceratid , haploceratid ( sub ) species , with their systematics , distribution and relevant references .
abstract here , we describe for the first time the occurrence of well preserved pictetia from the . . .
abstract here , we describe for the first time the occurrence of well preserved pictetia from the albian of northeastern japan ( miyako group ) and discuss the implications for the systematic assignment of the genus . a detailed systematic description of p . astieriana based on the newly collected material is given . earlier systematic assignment to lytoceratids resulted from similar conch morphology and ornamentation . based on the new knowledge of the development of the juvenile suture lines , pictetia is tentatively assigned to the hamitidae .
the pliensbachian - toarcian interval is characterized by several events of relatively short - live . . .
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urltoken
one of the most collected and most left behind , most loved and most hated ammonites of the yorkshire lias must be the genus dactylioceras , also known as the “common dac” . it is indeed one of the most common ammonites , at least at genus level , the seas of toarcian times must have been teeming with these animals , considering that what we find today is probably only the small fraction that made it to preservation .
in the 1970s to 1990s there have been heated scientific discussions on the classification of the dactylioceratidae e . g . between howarth and guex . the following articles follow the publications by m . k . howarth who in my humble opinion provided a framework for classification grounded in solid stratigraphy and statistics that is very consistent to what can be observed on the yorkshire coast .
with a little care when splitting the nodules ( and taking the negative with you for a transfer of torn off whorl sections if need be ) , a lot of the specimen can be preserved with intact mouth borders . when i do find these nodules nowadays , i tend to just carefully investigate if an ammonite is present in the nodule without splitting the nodule horizontally which raises the rate of success in preserving the ammonite in its entirety .
dactylioceras ( orthodactylites ) semicelatum ( simpson ) is the youngest of the group , found at the top of the grey shales , beds 28 to 32 ( howarth 1973 ) , which of course corresponds to the semicelatum subzone of the lower toarcian .
the 3 specimen pictured above perfectly show what is amazing about this species : the amount of variation in the shell forms exhibited may lead a collector who looks at these 3 specimen in isolation to think these are different species , yet when viewed in the context of all the specimen found in the above mentioned beds ( howarth examined more than 100 specimen for his “grey shales” paper ) , it becomes apparent that there is continuous variation between the different forms . ( if you read my blog very carefully , you might have noticed that i had previously labeled the coronate form of d . semicelatum as d . cf . crosbeyi – but after reading howarth´s paper completely and discussing the location of the find with mike marshall , i´ve come to the conclusion that it´s really a d . semicelatum )
for living organisms this is much easier to answer than for fossils : “a species is often defined as a group of organisms capable of interbreeding and producing fertile offspring” ( from wikipedia urltoken this is something that can be observed in the wild , today we even have genetics to measure the amount of differences in the genes . no such luck with fossils , we only have the rock and the impression and / or the petrified remains of the animal to judge from .
thus the species definition for fossil material is not comparable to the biospecies definition , it is only based on morphological similarities , also called a morphospecies .
with a large enough population of fossils , you can quantify the variation in the fossils in measurements such as number of ribs / whorl @ diameter , whorl breadth , whorl height etc . ( see previous post ) as a statistical population variance . comparing variances of different groups of fossils then helps to separate different morphospecies from each other . that brings us back to the semicelatum problem : when you find within that within a certain timeframe ( a restricted number of beds ) there is continuous variation of the fossil forms found within these beds , it is safe to assign it to the same species , then also called a chronospecies ( see also wikipedia urltoken and urltoken )
to quote howarth 1973 ( it just hits the nail on the head , i just could not write it any better in a single sentence ) : “d . ( o . ) semicelatum is more involute and has higher whorls than either tenuicostatum or clevelandicum . ” ribs per whorl can vary from 45 to 80 at 70 mm diameter .
the zonal ammonite dactylioceras ( orthodactylites ) tenuicostatum ( young & bird ) ( beds 20 - 26 ) has a more round whorl section , can have a lot more ribs / whorl ( between 90 and 140 ! at 70 mm ) than any of the other species ( allthough there is overlap at the bottom of the range , average ribs / whorl also increase from bed 20 to 22 ) . the largest specimen of d . tenuicostatum seem to be smaller than the largest specimen of d . semicelatum and d . clevelandicum . tenuicostatum - nodules are usually a bit softer than semicelatum nodules .
dactylioceras ( orthodactylites ) clevelandicum howarth ( bed 19b ) is more similar to d . tenuicostatum than to d . semicelatum or d . crosbeyi in being more evolute and having a round whorl section ( on the outer whorl ) , differences are mainly that d . clevelandicum has less ribs / whorl than d . tenuicostatum ( 70 at 70 mm for d . clevelandicum vs . about 100 for d . tenuicostatum ) and much more robust inner whorls , usually with spines . the rate of growth in whorl breadth is higher than in d . tenuicostatum , thus the umbilicus looks deeper than in d . tenuicostatum and at same diameter , whorl breadth is greater i . e . the whorl is thicker .
dactylioceras ( orthodactylites ) crosbeyi ( simpson ) is the oldest ammonite of the group , occurring only in bed 18 of the grey shales .
it is a quite rare , most of the time preserved only fragmentary as body chamber with crushed inner whorls .
d . crosbeyi is similar in appearance to d . semicelatum , just slightly more involute , but whorls are a higher and a lot thicker , ribs / whorl ( about 70 at 80mm ) at are usually lower than on similarly sized d . semicelatum .
this first part covered the lower toarcian dactylioceratidae that can be found on the yorkshire coast . as you might have seen from the notes in which beds the ammonites can be found , for the lower toarcian “dacs” it is sometimes helpful to know which bed they came from – for the upper toarcian “dacs” , this is most of the times essential to be able to properly identify them .
double nodule of d . ( o . ) tenuicostatum , one with pathology , both about 7 cm , purchased from yorkshire coast fossils / mike marshall
literature : m . k . howarth : the stratigraphy and ammonite fauna of the upper liassic grey shales of the yorkshire coast . bulletin of the british museum ( natural history ) , geology series , vol . 24 no 4 . london 1973
you might have noticed , i´ve deviated from my usual schedule of posting an article about every 2 - 3 weeks… there are a couple of reasons , none bad , which have kept me from posting . reason number 1 is that commitments from my daytime job have kept me unusually busy for january and february and this will stay that way at least until mid march , so you´ll have to wait for a new full article until about 3 - 4 weeks time .
in the “unfinished posts” queue is the first part of the dactylioceras article , dealing with the lower toarcian dactylioceras species . when looking at some of the ammonites i was photographing ( every little prep fault somehow gets exaggerated when you look through a lens… ) , i found that most of them needed some form of re - prep to comply to the same standard i´ve been trying to adhere to for the book . this is for example the reason why # 7 in the photograph , a dactylioceras ( orthodactylites ) clevelandicum , went back to the top of my prep queue : the inner whorls needed some more attention with the fine air pen and the air abrader – it had been found in 2002 and basically went straight to the drawer at that time .
double of dacytlioceras commune , 5 & 4 cm , thanks to dr . mike howarth for helping to correct my inital thoughts on this one…
a combo of amaltheus stokesi ( 5 . 5 cm ) , amaltheus bifurcus ( 2 . 5 cm ) , amaltheus wertheri ( 2 & 1 cm )
another article that´s in the “unfinished posts” queue for a long time already is about pathologies on yorkshire coast liassic ammonites , for the simple reason that literature about pathologies was somewhat thinly spread across a wide range of publications , most of the time with few pictures ( so important for the amateur collector ! ) . but thanks to prof . dr . keupp from fu berlin this has now changed ( urltoken ) : a brand new copy of his almost 400 page thick , large format , just released new atlas on cephalopod palaeopathologies has landed on my desk , i had only very little time to study it yet , but what i´ve seen so far is spectacular ( pictures galore ! ) and will surely set the scientific standard on this topic for years to come ( unfortunately it is currently only available in german ) . so through this new publication my “sick ammonites from yorkshire” post will take a giant leap forward and will be published after the first part of the dac post…
lytoceras is a rather “conservative” genus that remained relatively unchanged from the lower lias up to the upper cretaceous , its rarity in yorkshire having something to do with the water depth : lytoceras is considered a deep water genus that only occasionally strayed into the relatively shallow waters of the cleveland basin .
lytoceras seems to get more common during toarcian times , this may have to do with a temporary high in water levels that also allowed tethyan species like frechiella to migrate in .
all of the liassic species that occur in yorkshire have a more or less round whorl section , and have more or less evolute shells where the whorls hardly touch each other . the ribs on the shell generally show a typical fimbriation – a fringing of the ribs that leads to a characteristic shell pattern . a feature of the shell that is rarely preserved due to its fragilty ( both during times of embedding and during preparation… ) are the so - called flares – ribs that have developed into thin collar - like extensions of the shell .
finding a lytoceras with preserved flares is a real highlight – prepping it a real challenge , for the thin calcite flares almost break if you look at them – preparation is only possible in softer matrices where low impact prep methods ( e . g . air abrasion ) can be utilized .
this is a specimen from the maculatum subzone , which is relatively rare . l . fimbriatum is more common in the luridum subzone , but rarely well - preserved .
this specimen has no shell on the inner whorls , thus showing the beautiful suture and constrictions on the innermost whorls .
lytoceras ceratophagum and lytoceras cornucopia are very similar , l . ceratophagum has more radial ribbing whereas l . cornucopia has slightly rursiradiate ribbing .
lytoceras sublineatum differs from the other species in having a more compressed whorl section .
allthough howarth mentions the first two in his “the yorkshire type ammonites and nautiloids of young and bird , phillips and martin simpson” paper as holotypes , there is no further record of them in later literature . both oppel and wright had “ammonites gubernator” as a synonym for lytoceras jurense ( now perilytoceras jurense ) , which is assumed here as well .
buckman pictures the whitby specimen of simpson´s ammonites peregrinum as alocolytoceras peregrinus , but this is not mentioned later , either . due to the fragmentary nature of this specimen , this is not followed any further . trachylytoceras fasciatum is considered by howarth as a potential synonym of trachylytoceras nitidum , now lytoceras ( trachylytoceras ) nitidum .
frechiella subcarinata ( young & bird , 1822 ) , 8 . 5 cm diameter , port mulgrave , with a dactylioceras fragment and a belemnite phragmocone in the aperture
frechiella is one of the rarest yorkshire lias ammonites and in some respects also one of the oddest .
leukadiellinae ( middle toarcian ) and paroniceratinae ( upper toarcian , including frechiella ) but all still under hildoceratidae .
all are much more common in the tethyan realm , and are rare “strays” into the north - west european faunal province .
all members show a characteristically reduced , sometimes “ceratitic” suture ( named after the triassic ammonite genus ceratites , which showed a similar suture ) .
oxyparoniceras telemachi ( renz ) , 2 cm this is a member of the same subfamily , but not found in britain , but somewhat further south from barjac in the south of france ( and purchased by me ) .
well preserved specimen show a faint keel on a rounded , sometimes slightly rectangular venter , faint radial ribs , sometimes flat waves can be seen close to the umbilicus .
with almost all specimen i’ve seen ( and that’s not many… ) the body chamber is more or less crushed or imploded .
occurs only in the main alum shales , commune subzone , bed 54 ( howarth 1992 ) .
it is one of the rarest yorkshire coast lias ammonites , and many regard it as the “holy grail” of upper lias ammonites .
spots around hawsker bottoms – this is the one pictured above – i have not found one since , not even a fragment .
i´ve started this blog in may 2012 , and 36 blog posts later i can still say : it works for me ! it works for me because it drives me to write a post every couple of weeks , and that requires research into the ammonites i want to write about , photographs of the ammonites and maybe even a re - prep to make them presentable ( allthough that sometime pushes back the publication date , because when you see those fossils through the lense , it´s so much easier to notice all the imperfections in the prep - work… ) .
it´s sometimes hard to stick to the schedule , because i do have a ( non - fossil - related ) , sometimes stressful day job and sometimes require a time - out from working at the keyboard , but i think it´s the right sort of methodology to keep work on the ultimate goal – the book – going .
i´ve made some wonderful new contacts through people who have come forward and commented on posts and revived some old contacts who allowed me to photograph some of their beautiful fossils . thanks to all of you and i´d hopefully meet you next year to photograph some more !
looking at the map , it does seem so… of course , most of the readers are in great britain , that´s where the fossils come from , those are the readers this english language blog is made for . you know what they say about a prophet in his own country , i guess it´s the language issue why there is only a comparatively small participation from my fellow countrymen in germany . but what makes me particularly proud is the worldwide readership…isn´t the internet a wonderful thing sometimes ?
and a few little steps can make it so much easier to follow this blog , as you get an e - mail whenever i write something new .
if you don´t like to post a comment here , you can reach me in the ukfossils forum ( urltoken ) as andys and on the german steinkern forum ( urltoken ) as andys ( for both forums : you still need an account there to post messages ) .
if you read the title of this blog and start to worry that i might stop working on the book and on the blog – well , don’t . this is just referring to the subject of this post , the ammonite genus ovaticeras… the title specimen by the way ( you might have guessed by the quality of the prepwork ) is a specimen purchased from mike marshall . maximum size of the ovaticeras on this piece is 8 cm .
ovaticeras is a somewhat rarer ammonite which seems to be very restricted , both in terms of local distribution ( it’s apparently only really documented from britain , with its main occurrence in yorkshire ) and in terms of its relative short - livedness ( it has only been found in the approx . 35 cm of the so called ovatum bed at the top of the falciferum subzone of the lower toarcian ( of course named after the species o . ovatum ) and shortly below it . it is thought to have descended from harpocas falciferum ( howarth 1992 ) and apparently left no descendants itself – end of the line .
i have found ovaticeras ovatum at saltwick bay , at hawsker and at ravenscar , but you should be able to find it everywhere on the yorkshire coast , where there’s an outcrop of the aforementioned bed .
the oval whorl shape of ovaticeras is quite characteristic , as are the sloping umbilical walls without an edge , which differentiates it from large eleganticeras body chambers .
comparison of umbilical edges of eleganticeras ( top ) and ovaticeras ( bottom ) , both approx . 12 cm
adult specimen have a bit of a “hood” at the end of the body chamber , where the keel slightly overarches the whorl . the ribs are those of a typical harpoceratid , of weak falcoid form , receding to mere sinuous growth stripes on adult specimens’ body chambers . it does have a simple keel with smooth areas to the side of it that also grows weaker on large body chambers .
this large , 17 cm , complete specimen was found on oct 7 , 1991 at saltwick bay in a large nodule with a strong pyrite crust and was extracted from the nodule using hammer and small chisels alone ( on the kitchen table of our holiday flat , if you need to know… ) it is not my prettiest specimen , but my largest and the first of the species i’ve found .
this partial specimen shows the nice characteristical sutures of ovaticeras . must be getting close to christmas , i see christmas trees everywhere…
legend has it that st . hilda , founding abbess of whitby abbey , turned a plague of snakes to stone and threw them off the cliff , thus creating the ammonites we can find there today . this legend was immortalized by alpheus hyatt in 1876 by naming the ammonite genus i´d like to present to you next after her : hildoceras .
in victorian times , snake heads were often carved on ammonites to capitalize on this legend – today there seems to be a renaissance of this art going on , and the quality you´ll find on places like ebay is usually quite good , although these are mostly dactylioceras ammonites .
hildoceras bifrons is the lead ammonite for the bifrons zone of the lower toarcian . it has a strong spiral groove , strong ribbing on the external half of the side ,
hildoceras semipolitum has a higher whorl section than h . bifrons , both spiral groove and ribbing are finer . the outer whorls overlap the inner whorls to a degree that
the ribs on the inner whorls are no longer or just about visible . as h . semipolitum is considered a descendant of h . bifrons , there are many intermediates .
hildoceras lusitanicum ( also known under the synonym hildoceras sublevisoni ) is very similar in ribbing to h . bifrons , the main difference is the missing spiral groove on the side of the whorl .
in the stokesi subzone of the yorkshire coast , there are very few cephalopods other than amaltheus . there is the very occasional lytoceras , maybe even a very rare nautilus and a few immigrant ammonites from the tethys , a new ocean that had begun to form during the triassic ( for a visualization of the movement of continents during the ages see e . g . urltoken
one of these immigrant genera from the tethys is protogrammoceras , an early member of the hildoceratidae family of ammonites , that is going to be one of the dominant ammonite families in the toarcian , with genera like hildoceras , harpoceras , eleganticeras , hildaites , pseudolioceras etc .
much of the evolution leading to protogrammoceras is assumed to have occurred in the tethys , so appearance of protogrammoceras in yorkshire seems rather “sudden” .
protogrammoceras is also rather a rare ammonite in yorkshire , finding good specimen requires intense searching of the hard flat limestone nodules of the stokesi subzone .
diagram of rib density differences between p . ( m . ) nitescens and p . ( m . ) geometricum
p . ( m . ) nitescens has lower rib densities on the outer whorls , ribs are more angled backwards ( rursiradiate ) on the outer half of the whorl than p . ( m . ) geometricum .
p . ( m . ) geometricum has higher rib densities throughout , the ribs do not angle backwards as much as p . ( m . ) nitescens
protogrammoceras ( m . ) nitescens ( left , 7 cm ) and protogrammoceras ( m . ) geometricum ( right , 6 cm )
this interesting cluster of 8 protogrammoceras , 1 amaltheus stokesi and various bivalves was found in july 2009 . by their rib densities , of the 8 protogrammoceras 2 - 3 are p . ( m . ) geometricum or intermediates , while the other 5 are p . ( m . ) nitescens .
the following 2 large specimen don´t really fall into the rib density range given by howarth with ribs / whorl over 40 , but they are also larger than the specimen howarth used for his rib density observations .
identification of species by rib densities is certainly no exact science , but they could also be intermediates from p . ( p . ) occidentale ?
in the first part of this blog post i described the yorkshire liassic crinoids , now´s the time to show you the starfish .
it feels like starfish are even a bit more rare than crinoids – at least with crinoids you get the obvious isolated segments ( ossicles ) in most sediments . disarticulated starfish remains are less obvious , though i guess they must be there as well , most yorkshire lias sediments are just difficult to prepare for microfossil analysis .
most articulated starfish remains in my collection are from the figulinum – stokesi subzones of the yorkshire coast , as are the first three .
“yorkshire” seas also fed the brittle stars better 😉 – dorset specimen of the same species are usually considerably smaller .
palaeocoma species ( p . egertoni , p . gaveyi ) under one species p . milleri . )
this one was found in a fresh cliff fall on a block of softer sediment , sensitive to both drying out / cracking and falling apart when subjected to water .
mike marshall kindly dry - cut the block to size and stabilized it with some epoxy putty . having thus safely arrived home , a couple of minutes of
air abrading brought the winding arms of the 9 cm diameter brittle star to light .
this is the said large specimen of palaeocoma with the arm length of 15 cm ( stretched out ) and an “arm span” ( as embedded ) of more than 22 cm .
the long arms sink deep into the thinly bedded sandstone with harder and softer layers , with the very tips less than 0 . 5 mm thick . this fossil was prepped with alternating runs of air pen ( for breaking through the harder layers ) and air abrader ( for the detailed work around the fossil ) .
it could be a replacement arm ( allthough it looks too small for it ) . i have not seen any pictures of what replacement arms with brittle stars look like , i you have , please let me know…
this starfish was found in march this year . it sits in a little block about 23 cm wide and was again prepped with air pen / air abrader .
the central disc is about 3 . 5 cm wide – the arms must have really been long on this one , if they had been preserved…
the embedding rock seems to originate from beds around the oyster bed , showing some oysters as well .
recent brittle stars are known to gather where there is a large supply of nutrients , i . e . in the deep sea on decaying whale carcasses .
the slab was found in 1999 on the way back from a long day out at hawsker ( i told you , it always happens to me like this… ) ; as the tide came in already , it had to be left on the beach and was hidden in a secretively marked spot .
the reddish covering sediment was found to be preppable using potassium hydroxide ( koh ) pellets , and over the course of some months it was treated in a large cement tub . it is now awaiting finishing touches in a big enough air abrading chamber ( planned for 2013… )
the slab had an eroded amaltheus stokesi on the back , so it must originate from the stokesi subzone .
this small starfish sits on the same slab as the palaeocoma specimen of the last picture . it is only relatively small ( 4 cm diameter ) and very fragile .
this is the elusive sun starfish . i have only ever found one specimen myself , but could not salvage it without risk ( huge block , last day of the holiday… ) i notified a local collector who had it cut out of the block with a diamond still saw and had it prepped professionally , it is now on public display in a shop in robin hoods bay .
the small brittle stars associated with the hispidocrinus scalaris crinoid i showed you in the previous post are just too small to be identified – a little over 1 cm diameter . i have tentatively put them towards sinosura , since larger specimen of sinosura have been found with these crinoids .
these tiny little brittle stars are preserved so life - like , with even some of the finest hairs still attached , truly a moment frozen in time .
i´ve recently had the opportunity to prep a beautifully preserved p . milleri which is , unlike all the other p . milleri shown here before ( did you notice ? ) not prepped in oral aspect ( from the underside ) , but in aboral aspect ( like you would see it crawling around in and over the sediment ) . it is perfectly preserved and could be teased out of the relatively soft shale with low air abrader pressure in about 45 minutes . congratulations to the finder ( d . clark ) and thanks again for letting me picture it here !
brittle star palaeocoma milleri , width approx . 20 cm , collection d . clark
echinoderms , more specifically starfish and crinoids . it really came more as a by - product of hunting for ammonites , mostly when my rucksack was already full on the way back , tiredly stumbling across the large blocks while taking a different route across the boulder strewn beach on the way home . it also happens that i pick up rocks with crinoid or starfish content when i´m frustrated because there is nothing else ( meaning decent ammonites ) to find – almost as if you have to be in a certain state of mind to notice these fossils , when your attention is no longer focused on other fossils , similar to when you start hearing strange sounds in the dark night when your visual sense becomes useless…
this of course has to do something with the difference in the “search mode” when your looking for ammonites vs . starfish / crinoids : with ammonites , on the yorkshire coast you´re mostly looking for concretions , while with starfish / crinoids you´re carefully surveying the surfaces of ( potentially large ) fallen blocks – this also explains the of course totally unobjective observation that i tend to find crinoids / starfish mostly on the return from a location : i tend to use the easier way across the large blocks , and it´s usually later in the day , which makes for nice low angled light and better chances to see the delicate fossils…
for intact , articulated preservation , fragile animals like starfish and crinoids need fast embedding , because decay sets in quickly , e . g . for brittle stars , already after half a day . brittle stars cannot free themselves when they´re suddenly covered by more than 5 cm of sediment – most of the brittle star fossils on the yorkshire coast have probably been created by rapid burial in sediment , like a sediment avalanche – truly a moment frozen in time . some of the crinoids that can be found articulated are thought to have been deposited in scour troughs .
still – “greatest liklihood” does not mean they’re common fossils , finding an articulated crinoid or starfish remains a great rarity . the falciferum zone is the odd one out here , since benthic conditions were mostly anoxic during this time ( very little oxygen at the bottom ) – so there are no starfish , and crinoids that occur were usually attached to drifting logs at the surface of the sea .
some of these have been purchased , some reside in collections other than my own and are pictured here by kind permission of their respective owners – you will see that in the notes for the fossils .
generally preparation of starfish and crinoids most of the time is a difficult and time consuming task .
their delicate structures are usually firmly embedded in the sediments and can only be retrieved if there is a difference between the surrounding matrix and the fossils which are usually preserved as calcite or pyrite . this difference can either be a difference in hardness , when the fossils are harder than the matrix – these fossils can be prepared mechanically , i . e . needles , airpens or – you might have guessed – air abrader . if there is no difference in hardness , there can also be the option of chemical preparation – when the fossils are more resistant to certain chemicals like acids or alkaline solutions than the matrix . in rare cases , the environment ( or rather what we put into it – sulphur dioxide / nitrogen dioxide from burning fossil fuels reacting with water to form sulfurous / sulfuric resp . nitric / nitrous acid ) or certain naturally occuring humic acids can do the job for us – but that is only really the exception .
this is one of the first more or less articulated crinoid crowns i´ve found on the yorkshire coast .
another specimen found by keeley and adrian which they kindly let me prep and photograph shows the crown in association with an oistoceras ammonite , which places the crinoid in the figulinum subzone of the lower pliensbachian .
these crinoids only have a very short stem ( only a few segments ) , which i´ve never found preserved so far .
this is the crinoid specimen that really got me seriously started to try and collect all the known yorkshire liassic crinoids . it was found on a very warm summers day in july 2007 when i was out collecting with friends and had found nothing at all up to this point – i picked up this 30 x 20 cm slab with some faint crinoid traces and put it in my bag so it at least felt like i had found something… at home i started prepping it with an air abrader ( iron powder ) and followed the visible arms of the crinoid into the rock . to my amazement more and more stems and arms appeared until after about 60 hours of prep work almost the whole slab showed a deathbed of multiple hispidocrinus crinoids in an early state of decay . when looking carefully at the slab , you can even notice tiny little brittlestars that have either fed on the decaying crinoid or had used the crinoid to achieve a higher up filter feeding position or even benefit from the crinoids´excretions and got embedded with it .
another specimen was found in a small 12 x 15 cm which was initially split after finding it since the outside did only show very faint crinoid traces . as the split showed a crinoid inside , it was glued back together again and air abraded in about 20 hours .
it shows two crowns , with the larger one having all it´s arms folded unto itself . and of course there´s another small brittlestar ( 5 o´clock position at the bottom ) …
this lens comes from the tenuicostatum zone of the lower toarcian and shows remains of seirocrinus subangularis and was prepared using an air abrader . on the inside , this lens consists of almost 100 % of crinoid ossicles amalgamated into a solid calcitic core .
another specimen showing a beautiful crown of seirocrinus was found by my friend klaus , who paintakingly prepared this specimen using potassium hydroxide pellets over the course of a couple of weeks , the final touchers were again made with an air abrader . this specimen also handily shows a dactylioceras tenuicostatum ammonite on the back of the nodule which tremendously helps dating it !
this crinoid was a surprise find on my birthday this year ! it sat neatly on the edge of a fallen rock most likely of oxynotum zone age and when found i had thought it was a hispidocrinus in an unusual , almost 3d preservation . the surprise came at home when i prepped it using the air abrader and noticed that it did not have the characteristic spines of a hispidocrinus . dr mike simms kindly identified it as an early isocrinus robustus .
this beautiful colony of pentacrinites dichotomus from the jet rock in the whitby area was found by mike marshall who prepared it by stabilizing the exposed weathered side of the thin fragile slab with a layer of epoxy putty and prepared it from the other side using an air abrader . the colony is nicely set into a slab of top jet dogger to stabilize it .
this beautiful section of a piece of solid black jet with a juvenile crinoid anchored to it was kindly given to me by a friend . it gives more evidence to the observation that some crinoids have used floating logs for anchoring themselves to during their lifetime and filter fed in the surface waters .