PHYLUM PRIAPULIDA

PHYLUM PRIAPULIDA (Cacing Penis)

 

PHYLUM PRIAPULIDA atau sering kita sebut Cacing Penis

• Cacing priapulida atau di kenal dengan nama cacing penis adalah salah satu phylum dari cacing laut dengan tentakel yang dapat di panjangkan
• Tubuh priapulida terdiri atas dua bagian, yakni prosoma dan tentakel. Prosoma seringkali di sebut dengan introvert. Prosoma dapat di gambarkan berupa batang yang dapat di tarik sehingga di sebut introvert. Prosoma mempunyai mulut pada bagian akhir tubuhnya.

Karakteristik organisme Priapulida

• Simetris bilateral dan berbentuk tabung
• Tubuh memiliki lebih dari dua lapisan sel, memiliki jaringan dan organ
• Memiliki rongga tubuh (coelom)
• Struktur tubuh di mulai dari mulut sampai anus
• Tubuh di bagi atas dua bagian yakni prosoma dan tentakel
• Memiliki suatu sistem saraf yang tersembunyi dan tali saraf ganglion
• Tidak memiliki sistem peredaran darah tetapi memiliki sel darah  yang coelomic
• Reproduksi seksual dan gonokoristik
• Makanan terdiri atas cacing laut lainnya
• Hidup pada seluruh perairan laut

CIRI-CIRI UMUM PRIAPULIDA

-  Priapulids are small, yellow or brown, carnivorous worms.

-  They are free-living and partly (sebagian) bury themselves in marine sediments of polar, temperate, and tropical seas worldwide, at depths down to several kilometres

-  There are only 16 known priapulid species, but at least three of these occur in the Arctic: Priapulus caudatus, Priapulopsis bicaudatus, and Halicryptus spinulusos.

-  Priapulids have separate sexes (gonokhorik) and juvenile priapulids periodically moult their outer cuticle before becoming an adult.

-  Two closely allied (sekutu) priapulid species, Priapulus caudatus from the Arctic and P. tuberculatospinosus from the Antarctic, are morphologically similar as both species have a thick proboscis and a caudal appendage that resembles (mirip) a mass of tentacles - but these two species are genetically divergent.

-  Evolution has occurred molecularly, but not morphologically, resulting in two species that look the same, but are very different genetically!

-  Protonepridia (kidney) associated with the gonads (urogenital system)

-  Caudal appendage for gas exchange

-  No circulatory system

-  Complete gut

-  loricate larvae

-  Marine benthic burrowers

-  There are no specialized sense organs or vascular or respiratory systems (hemerythrin is the protein responsible for oxygen transportation).

-  The Priapuloidea are hermaphroditic, and their male and female organs, which are one with the excretory organs, consist of a pair of branching tufts (lempeng), each of which opens to the exterior on one side of the anus