Identify major groupings within the Lophotrochozoa and Ecdy gg g sozoa ; describe distinguishing features among groups, where on Earth these organisms are typically found, and how they make a living Solution Lophotrochozoa are a group or taxon of protostome animals. The taxon consists of 2 groups- trochozoans and lophophorata. Trochozoans are characterized by the development of mouth before anus in the embryo.They are worm like and produce trochophore larvae - larvae that have 2 bands of cilia around their middle. Lophophorata, on the other hand, are grouped by the presence of lophophore characterized by a fan of ciliated tentacles surrounding their mouths. These animals exhibit radial cleavage. Lophotrochophora includes the following phyla 1. Phylum Ectoprocta: These are mostly marine coelomates that use lophophore for feesing. They secrete and live in zoecium (chitinous chamber). 2. Phylum platyhelminthes These are mostly parasitic acoelomates. Some may live as scavengers or commensals. The are flat and ribbon-shaped. They have an incomplete gut, no circulatory system, and a simple nervous system. Their excretory system has small tubules lined with ciliated flame cells. They are hermaphrodites. 3. Phylum Rotifera These are small aquatic pseudocoelomate animals. They are mostly free living and a few are paraitic. They have a ciliated food gathering organ at the tip of the head known as corona. They have jaws in the pharynx and their digestive system has separate mouth and anus. They have rudimentary circulatory system and they have separate sexes. 4. Phylum Annelida They are segmented coelomates with a closed circulatory system. Their excretory system includes nephrida. They have a digestive system with separate mouth and anus. Gas exchange is through skin.They have setae. They are found in both terrestrial and aquatic habitats. They can be parasites, carnivores, predators or scavengers. 5. Phylum Nemertea They are partially coelomate and partially acoelomate animals. They are free living and possess proboscis - a long muscular tube covered by a sheath to capture prey. They have a complete digestive system, a simple nervous system, and a closed circulatory system. 6. Phylum Phoronida: They are coelomate and marine. They use lophophore for feeding. They have a U-shaped gut and they secrete and live in a chitinous tube. 7. Phylum Brachipoda: They are characterized by the presence of 2 calcified shells. Ecdysozoa also belons to the group of protostome animals characterized by a three layered cuticle which is periodically molted,a process known as ecdysis. They lack locomotary cilia. They produce amoeboid sperm. Their embryos donot undergo spiral cleavage unlike other protostomes. The group includes Phylum arthropoda The phylum includes invertebrate animals with an exoskeleton. They have jointed limbs and their cuticle is made of chitin. They are segmented with an open circulatory system and a ladder- like nervous system They are found in both a.

1. Identify major groupings within the Lophotrochozoa and Ecdy gg g sozoa ; describe
distinguishing features among groups, where on Earth these organisms are typically found, and
how they make a living
Solution
Lophotrochozoa are a group or taxon of protostome animals. The taxon consists of 2 groups-
trochozoans and lophophorata. Trochozoans are characterized by the development of mouth
before anus in the embryo.They are worm like and produce trochophore larvae - larvae that have
2 bands of cilia around their middle. Lophophorata, on the other hand, are grouped by the
presence of lophophore characterized by a fan of ciliated tentacles surrounding their mouths.
These animals exhibit radial cleavage.
Lophotrochophora includes the following phyla
1. Phylum Ectoprocta:
These are mostly marine coelomates that use lophophore for feesing. They secrete and live in
zoecium (chitinous chamber).
2. Phylum platyhelminthes
These are mostly parasitic acoelomates. Some may live as scavengers or commensals. The are
flat and ribbon-shaped. They have an incomplete gut, no circulatory system, and a simple
nervous system. Their excretory system has small tubules lined with ciliated flame cells. They
are hermaphrodites.
3. Phylum Rotifera
These are small aquatic pseudocoelomate animals. They are mostly free living and a few are
paraitic. They have a ciliated food gathering organ at the tip of the head known as corona. They
have jaws in the pharynx and their digestive system has separate mouth and anus. They have
rudimentary circulatory system and they have separate sexes.
4. Phylum Annelida
They are segmented coelomates with a closed circulatory system. Their excretory system
includes nephrida. They have a digestive system with separate mouth and anus. Gas exchange is
through skin.They have setae. They are found in both terrestrial and aquatic habitats. They can
be parasites, carnivores, predators or scavengers.
5. Phylum Nemertea
They are partially coelomate and partially acoelomate animals. They are free living and possess
proboscis - a long muscular tube covered by a sheath to capture prey. They have a complete
digestive system, a simple nervous system, and a closed circulatory system.

2. 6. Phylum Phoronida:
They are coelomate and marine. They use lophophore for feeding. They have a U-shaped gut and
they secrete and live in a chitinous tube.
7. Phylum Brachipoda:
They are characterized by the presence of 2 calcified shells.
Ecdysozoa also belons to the group of protostome animals characterized by a three layered
cuticle which is periodically molted,a process known as ecdysis. They lack locomotary cilia.
They produce amoeboid sperm. Their embryos donot undergo spiral cleavage unlike other
protostomes.
The group includes
Phylum arthropoda
The phylum includes invertebrate animals with an exoskeleton. They have jointed limbs and
their cuticle is made of chitin. They are segmented with an open circulatory system and a ladder-
like nervous system They are found in both aquatic and terrestrial environments and they are
hermaphrodotic.They are mostly parasites.
Phylum Onychophora
They are elongated, soft bodied and many legged animals. They are segmented with no
exoskeleton. Their body cavity is a haemocoel. They are predators and are found mostly in
terrestrial habitats.
Phylum nematoda
They are slender worms with a radially symmetrical head. Their mouth has either 3 or 6 lips.
They have a adhesive claudal galnd at their tail tip. They donot have a stomach. the pharynx is
directly connected to the muscless intestine. They are dioecious. They are both free-living and
parasitic species.
Phylum Loricifera
These animals have lorica, a head, mouth and digestive system. they donot have circulatory
system and endocrine system. They are dioecious. They are found mostly in marine
environments.
Phylum nematomorpha
They are parasitoid animals with an external cuticle without cilia. They donot have excretory,
respiratory, or circulatory systems. They have a nerve ring and a ventral nerve cord. They have a
non functional gut and they are dioecious. They are found both in fresh water and terrestrial
habitats.They are free-living but the larvae are parasitic.
Phylum Tardigrada
They are eight-legged watre dwelling segmented micro-animals.They have barrel-shaped body.
Their legs donot have joints. Their brain develops in a bilaterally symmetrical pattern. They have

3. a tubular mouth armed with stylets. They have a haemocoel body cavity. They are found in moist
environments. They are carnivores, phytophagous, bacteriophagous, or cannibalistic on their own
species.
Phylum Kinorhyncha
They are small marine invertebrates. They are segmented limbless animals with a body of 11
segments. The body wall has thin syncitial layer which secretes cuticle. They donot possess
circulatory system. Their head is completely retractable and is covered by neck plates called
placids when retracetd. They eat diatoms or organic matter.
Phylum Priapulida
They are cylindrical marine worms. They donot possess circulatory or respiratory systems. They
are gonochoristic. Their general body shape and their extensible spiny eversible proboscis recalls
the shape of a penis. They eat mud.