Hemichordata Urochordata and Cephaochordata Comparative Study on Excretory System and Nervous System  

Nervous System of Branchiostoma (Amphioxus)

Primary Excretory Organ:  In Hemichordata the proboscis gland or glomerulus is present inside the proboscis coelom, at the anterior portion of the buccal in the Urochordata on the dorsal side of the body above the nerve ganglion the neural gland take part in collecting the nitrogenous excretory material. In Cephaochordata excretion occur through the protonephridia, … Read more

Comparative Study of Digestive System in Hemichordata Cephaochordata and Urochordata  

Balanoglossus Digestive, Respiratory, Nervous System

Alimentary Canal: The alimentary canal in Hemichordata is straight, complete starting in mouth opening and an end in the anus, the alimentary canal in Hemichordata is much narrow. In Urochordata the alimentary canal is complete but it is not simple, it is not straight, intestine forms a loop, due to the presence of the intestinal … Read more

General Comparison of Hemichordata Urochordata and Cephalochordata  

Branchiostoma lanceolatum Amphioxus

The members of Protochordata are divided into three subphyla based on their notochord, Subphylum Cephalochordata, Subphylum Urochordata, and Subphylum Hemichordata.  Habits and Habitats: Members of Hemichordata generally live inside the burrow made in sand or mud in the solitary or colonial states. Members of subphylum Urochordata may be a sedentary or free-swimming line in the … Read more

Subphylum Urochordata: Characteristics Classification Examples 

ascidia

Characteristics Features of Subphylum Urochordata:  They live in marine water, almost present in all part of the world and in deep ocean as well as in shallow coastal areas.  They can live in solitary state, sometimes large number of Urochordate live in groups in solitary state, some of them show colonial form.  They are generally … Read more

Examples of Subphylum Urochordata

pyrosomes member of Urochordata

Ascidia:  It is solitary Urochordate generally live in groups on the rocks, it presents in sedentary state and lives in all depth of the ocean, have great similarity with Herdmania. Size is more than other Urochordate as compared to other members of Subphylum Urochordata, around 10 cm to 15 cm long.  It is cylindrical in … Read more

Examples of Subphylum Urochordata: Clavellina, Salpa, and Doliolum

salpa free swimming stage

As examples of Subphylum Urochordata, we will discuss some Urochordata genus, their general characteristics features, Clavellina, Salpa, Botryllus, Ascidia, Ciona, Molgula, Pyrosoma, Doliolum, Oikopleura, Ciona.  Clavellina: Examples of Subphylum Urochordata:  Clavellina is a colonial Urochordate, generally observed in shallow coastal areas attached to the rock. The individual zooids are connected to the colony with the … Read more

Classification of Subphylum Urochordata (3 Important Diagram)

pyrosomes member of Urochordata

Subphylum Urochordata has more than 2000 species and have different characters, based on the similarities and dissimilarity different workers tried to divide them in different ways. But here we will not discuss all the classification approaches of all workers, we only discuss the most adopted classification scheme of subphylum Urochordata by Storer and Usinger.  According … Read more

Herdmania: Morphology Digestive Excretory Reproductive Respiratory System 

External Morphology of Herdmania

What is Herdmania:  Herdmania is a marine animal that generally lives at the bottom of the ocean floor, remains in a sessile state. Herdmania is like a pouch due to its wrinkled outer covering or test.   Systematic Position of Herdmania:  In the animal kingdom when we try to place Herdmania we face difficulties due to … Read more

Affinities and Systematic Position of Herdmania ( 20 Important Similarity)

Herdmania

Affinities of Herdmania with Non-chordate:  Like porifera and coelenterata Urochordata are sessile live in marine environment.  Larval eyes and otocysts present in Urochordata show great similarity with some invertebrates.  In Herdmania intestine have typhlosole which also present in some other invertebrates.  Herdmania sometimes live in colonial form which shows great resemblance with some other invertebrates.  … Read more