
mesacanthus

aadyakaala devonian skotlaandil ninnulla acanthodian malsyathinte vamshanasham sambhavicha oru janussaanu mesacanthus ('madhya nattellu'). devonian acanthodianmaaril ettavum aadimamaaya onnaanith.
vivaranam.
"mesacanthus" body phosilukalkku pectoral, pelvik, guda, dorsal phiin nattellukalum pectoral, pelvik phiin nattellukalkkidayil edayilulla oru jodi prepelvic nattellukalum undu. avaykku cheruthum alankarikkaathathum vajra aakruthiyilullathumaaya skeyilukalum undu. agassis parayunnathanusarichu, eee janussinu oru prathyeka vaalumund, athil mukalile loob moorchayulla pooyintilekkum thaazhathe loob oru cheria trikonamaayum vyaapikkunnu. mothatthil eee januss cheruthum (sharashari neelam = 30 millimeter) shareeraghadanayil paranjaal, acanthodianmarkku valare yaadhaasthithikavumaanu. 
vargeekaranam.
1888 ll ramse trackware sthaapicha eee januss munbu luis agassis akaanthodukalkk nalkiyirunna chila enangale ulkkollunnathinayi nirmikkappettu. mesacanthus michelli, mesacanthus pusilus, mesacanthus peechi, mesacanthus coriasius enniva eee enangalil ulppedunnu. thaazhathe pazhaya chuvanna manalkkallukalilum madhya pazhaya chuvanna manalkkall koottangalilum eee januss kaanapedunnu, "m". pusilus, "emm. peechi "," emm. madhya devonian, emm ennivayil ninnu ariyappedunna coriasius. lover devonian vamshathil ninnulla ariyappedunna oreyoru inamaanu michelli. arther smith woodward audyogikamaayi "emm" ennathinu paryaayamaayi. peechi "," emm. 1891-ll coriasius. 2015-ll peerjil prasidheekaricha oru patanam backie rund middle devonian speesheesukale ("mee. pusilus "umm" emm. peechi ") avayum parasparam verthirichariyaan kazhiyillennu kandethi. athinaal, skotlandile oorkaadiyan thadatthil ninnum midu land thaazhvara pradeshangalil ninnumulla rund enangal maathrame nilavil saadhuvaayi kanakkaakkappedunnulla "m. lover devonian, "emm" ennivayil ninnulla michelli. madhya devonian bhashayil ninnulla pusilus.

