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10. Svalgsträngsdjur Till Ryggradsdjur

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10. Svalgsträngsdjur Till Ryggradsdjur svag ringfåra nära bakkanten. Gonaderna börjar uppträda i HEMICHORDATA W. Bateson, 1885 höjd med de mittre gälporerna. På metasomet kan små röda {hemikårdáta} (5–7 gen., 7–11 sp.) fläckar förekomma. S. pygmaeus blir blott ≤3 cm lång, har [Gr. hemi = halv + phylum Chordata : (se nedan)] 9–22 gälporpar, det ≈4 ggr längre än breda prosomet saknar Bilateralsymmetriska, osegmenterade, solitära el. koloni- längsfåror och är täckt av små vårtor. Dess färg är mjölkvit bildande, bentiska marina djur, med kropp bestående av 3 till ljusgul, medan kragen är ngt mörkare gul el. gulbrun. avsnitt, pro-, mesooch metasom (proboscis, krage och Kragen är bredare än lång med en ringfåra nära bakänden. bakkropp). Förutom de båda nedanstående klasserna plägar Gonader börjar uppträda bakom gälregionen. En 4:e, en oceanisk, geleartad, sfärisk, ≈1 cm Ø, ciliebandförsedd rödaktig art (släktets typart) med mörkare röd krage, S. larv från Biscaya & Bermudas, kallad Planctosphaera mereschowskii (Nicolas Wagner, 1885) [Konstantin Sergeje- pelagica Spengel, 1932 ges status av egen klass, Plancto- wicz Mereschkowski, 1854–1921, rysk protistolog, som sphaeroidea Van der Horst, 1936. Totalt är 92 (106?) tidigare hade honorerat Wagner med släktnamnet Wagnerella] recenta arter kända. är känd från Arktis (närmast från Vita havet och märkligt nog påstådd vara allmän i Adriatiska Havet, ehuru den senare ENTEROPNEUSTA Gegenbaur, 1870 populationen möjl. kan vara felbestämd). Den tycks ej nå en {enteråpnévsta} "Ollonmaskar" (4–6 gen., 6–10 sp.) längd av 1 dm & kännetecknas av att prosomet har en djup [Gr. enteron = tarm, inälva + Gr. pneusticos = för andning < Gr. dorsal längsfåra korsad av finare tvärfåror, kragen är lika pneumon = lunga] lång som bred & de ≈50 gälpor-paren börjar medio- Solitära, rörliga, externt rikt cilierade, skildkönade, branchialt. En obeskriven? art av Protoglossus van der maskformiga djur utan tentakelförsedda armar på kragen. Horst, 1927 (vars prosom är 2–2.5 ggr så långt som kragen) är Prosom (ollon) nyttjat som grävorgan. Luktar ofta starkt känd från Gullmarn (Silén 1950) (& skadade exemplar av jodoformlikt av bromfenoler. Adult storlek från blott 2–3 släktet har likaså iakttagits vid Fladen i Kattegatt), såvida det cm hos Mesoglossus Deland, Cameron, Rao, Ritter & ej rör sig om den närmast vid Holland funna P. koehleri Bullock, 2010 pygmaeus (Hinrichs & Jacobi, 1938) från (Caullery & Mesnil, 1900) [René Koehler, 1860–1931, fransk Helgoland till 1.8–2.5 m hos Balanoglossus gigas från zoolog, som skrev. bl.a. echinoderm-delen av Faune de France, Brasilien, ehuru hela maskar i praktiken är rara, enär ty han arbetade fr.a. med isopoder & echinodermer och var far metasomet är mycket ömtåligt hos alla gruppens arter & i till en av historiens första barnfilmstjärnor, dottern Madeleine, regel skadas vid fångsten. Tarm rak, med terminal anus. som 2 år gammal 1897 medverkade i den publikskrämmande Pharynxregionen står dorsolateralt i förbindelse med scenen i morbrödernas – Auguste & Louis Lumière’s – korta yttervärlden via ett antal gälspringor, vilka tillväxer i antal film ’Ankomst av ett tåg’ (& som 1907 hedrades i sjöstjärne- under djurens samlade livstid. Av totalt 5 fam., så saknas namnet Magdalenaster av fadern: även sonen Marcel, 1892– Spengelidae [Gen. Spengelia < Johann Wilhelm Spengel, 1958 & makan Jeanne, 1870–1926, ärades m. var sitt namn)] 1852–1921, zoologiprofessor i Giessen, som skrev om (≤7.5 cm lång, 14–30 gälpor-par, guldel. honungsgul ollon- Neapelbuktens enteropneuster], som innehåller 4 gen. & 15 kragregion med märkgröna fläckar, krage lika bred som lång, spp. världsvitt, norr om Medelhavet. Likaså saknas gonader börjar halvvägs ner längs gälregionen) el. ehuru Saxipendiidae (med en enda art) i Nordeuropa liksom mindre troligt den från USA (Maine) beskrivna djupt (ibland Torquaratoridae (likaså med blott en beskriven art från ≥40 cm) grävande P. graveolens Giray & King, 1996 [L. djuphavet). Den karaktäristiska larv-typen, Tornaria, visar gravis = svår, tung + L. olere, presens part. olens = stinka (av klara likheter med tagghudingarnas Auricularia & bromfenoler)] (≤47 cm lång, 60–142 gälpor-par, gräddvit Bipinnaria. Världsfaunan omfattar totalt 78 beskrivna goda ollon-kragregion krage dock stundom orangebrun, krage arter. bredare än lång, gonader börjar några få mm bakom kragen). Båda arterna har en dorsal längsfåra i ollonets bakre del & Harrimaniidae Spengel, 1901 kragen är insnörd nära bakkanten så att en ringformad fåra {harrimaníide} (4–5 g., 3–6 sp.) bildas där & framkanten av kragen är utformad som en slags Prosom i regel minst lika långt som (oftast tydligt längre än) huv runt ollonskaftet. (Sixten Bock efterlämnade ett opubl. kragregion. Bakkropp utan framträdande veck eller utskott; MS om arten?, under arbetsnamn P. simplex). Världsvitt kroppsvägg saknar ringmuskelfibrer. Ägg gulerika, omfattar fam. 5 gen. & 23 spp. En art av Protoglossus el. utvecklas ej t. att genomgå planktotrof larvfas. Av riktigt Saccoglossus iakttagen fr. siltbotten av 102 m djup ÖSÖ långsmala maskar påträffas 2 gen. i våra hav (≤5mm breda Persgrunden hade ett prosom, ideligen varierande i längd med längd:-bredd-kvot 20–50). En art av Saccoglossus mellan 1.7–4 gånger kraglängden & var överallt utom utmed Schimkewitsch, 1892 lär vara tagen i Öresund. Släktet bakkanten & i ett anteroventromediant område – täckt av kännetecknas av att prosomet är >3 ggr så långt som kragen. vitopaka pigmentfläckar. Prosomet hade en smal – men tydl. S. horsti Brambell & Goodhart, 1941 [Horst, Cornelius Jan – dorsomedian längsfåra längs hela sin längd. Där det vita van der , 1889–1951, disputerade i Amsterdam 1916, flyttade pigmentet ej täckte prosomet var det ljust gulbrunt liksom 1928 till Sydafrika, där han var prof. vid univ. i Johannesburg; abdomen. Spridda opakvita pigmentfläckar fanns dock även upprättade den berömda Inhaca Island Biological Station i på såväl abdomen som på den köttröda kragregionen, vilken Mozambique; jämte Hemichordata arbetade han med var ungefär lika lång som hög & hade en tydlig ringfåra just Madreporaria & fr.a. generellt med komparativ neurologi, framför bakkanten. Prosomets Ø varierade mellan ca 1.6–2 hjärnanatomi & paleontologi. Erhöll 1951 svenska KVA:s mm med hopdragningarna & kragens + abdomens längd Linné-medalj], S. ruber Tattersall, 1905, S. pygmaeus tycktes ej överstiga dubbla utsträckta prosomlängden. Hinrichs & Jacobi, 1938 (nu i Mesoglossus) är de 3 Gälspaltsantalet tycktes vara ett 40-tal. Denna art tycks vara nordeuropeiska beskrivna arterna. Sixten Bock, 1884–1946, identisk med Bock’s obeskrivna S. alborostratus. lämnade oklara manuskript, där det framgår att han ämnade beskriva S. alborostratus (n. nud,) en till synes liten art med Harrimania Ritter, 1900 {harrimánia} (1 sp.) ≠40 par gälspringor &vitt prosom fr. bl.a. Flatholmsrännan. [Släktets typart H. maculosa beskrevs i serien ’Papers from the Harriman Alaska expedition’ (Maj t.o.m. Juli 1899) efter Edward S. horsti blir ≤3 dm lång, har 100–140 gälpor-par, har både Henry Harriman, 1848–1909, chef för bl.a Union Pacific Railroad, en dorsal och en ventral längsfåra i det ≈3.1 ggr längre än (& e.g. Wells Fargo Express Co.) som ledde & sponsrade breda vita, gulaktiga eller skära prosomet. Kragen är längre expeditionen, känd från filmen ’Butch Cassidy and the Sundance än bred, utan ringfåra nära bakänden och gonaderna börjar Kid’] uppträda ca 1 mm bakom denna. Den snarlika S. ruber blir ≤2 dm lång, har 60–95 gälpor-par, har blott dorsal längsfåra kupfferi (von Willemoes-Suhm, 1871) {kópfferi} utmed de bakre 2/3 av det skära, ≈7–10 ggr så långa som [Karl Wilhelm von Kupffer , 1829–1902, tysk zoolog; prof. i breda prosomet och kragen, som är längre än bred har en Dorpat 1858, därpå i Kiel 1866, i Königsberg 1876 och 1880 i 1 München. Han arbetade främst med vertebrater, men även bl.a. skiljer den bakre kraghalvans sista tredjedel från de främre med Tunicata] båda tredjedelarna. Bakom ringfåran är kragen helt slät. G. D:<20–>40, F:ollon blekt gulbrunaktig; krage & abdomen i marginatus tycks vara rar i Bohusläns skärgård, men är ej liknande nyans men ej så bleka; gonader hyalint aprikos- alls rar i inre Skag. nedom ≈90 m (ett exemplar dock ertappat rosa; nervsystem brunt; tarm framtill brun, bakåt grönaktig, på 66 m djup NV om Nordkoster), även om kompletta L: 9; Ø:≈0.7 (längd:bredd-kvot ≈12), MB, Öres.-Bohus. & exemplar – som hos så många andra av gruppens arter – är Grönland. Har dorsolaterala gälporer, ej rent laterala som hart när omöjliga att få upp medelst skrapning. hos den med ungefär likartade kroppsproportioner, närmast från Norska Havet & Scotland kända gyllengula Stereo- Lankester, 1877 balanus canadensis (Spengel, 1893). PTEROBRANCHIA {pteråbránkia} (1 g., 1 sp.) [Gr. pteron = vinge, fena el. Gr. pteridios = (be)fjädrade + Gr. Ptychoderidae Spengel, 1893 {ptykådéride} (1–2 g., 2–3 sp.) branchia = gälar] [Gen. Ptychodera < Gr. ptyche, ptyx, genit. ptychos = veck,lager + Små, fastsittande, i regel kolonibildande, rörbyggande Gr. deros, deras poet. form av derma =hud, skinn, läder] hemichordater med U-böjd tarm, vars anus mynnar i Prosoma aldrig mycket längre än kragregion (<3% av kragregionen. Kragen bär ett eller flera par tentakelbärande maskens totallängd). Bakkropp med utskott i form av armar. Endast tre monogeneriska familjer, Rhabdopleuridae genitalveck i framregionen & hepatiska fickor i mitt- Harmer, 1905 (8 arter totalt), Cephalodiscidae (18 arter totalt) regionen. Med små ägg, som utvecklas till pelagiska och Atubaridae (1 art) finns. Cephalodiscus
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