PHYLUM LORICIFERA

Christen Jene CorilloLora Mae Garcia

Undescribed species of Spinoloricus

(Loricifera; stained with Rose Bengal).

PHYLUM LORICIFERA

“loricus”- corset, girdle

“ferro” – carry, bear

“girdle bearers” about 100 species discovered microscopic (>0.5 mm) marine

- from shallow to deep water

- between particles of sediment multicellular

Characteristics:

• Bilateral, unsegmented, and probably pseudocoelomate

• Body divided into a head, neck, and thorax, all retractable into an abdomen

• Abdomen housed in cuticular lorica• Mouth is located at the end of oral cone

beset with stylets• Gut complete

• No circulatory or respiratory organs• Nervous system present• One pair of protonephridia• Gonochoristic; development includes

unique Higgins-larva• All inhabit marine, interstitial

environments, first found in clean shell-gravel sediments

Defining Characteristic

• spinelike, chitinous scales (scalids) on the introvert are operated by individual muscles

• set of spiny plates called a lorica around their abdomens

• spiny head• head, neck, and thorax retract, like a

telescope, into the lorica

ANAT

OM

Y

EXTE

RNAL

INTE

RNAL

Three body regions:

1. head

- mouth, oral stylet

- rings of scalids

2. neck

3. trunk

- lorica/corselet

Larvae

- caudal feet

Brain Ganglion Stomach Esophagus

Ventral view of adult female loriciferan (Nanaloricus mysticus)

Nanaloricidae

Pliciloricidae

Nanaloricus

PliciloricusRugiloricus

ArmorloricusPheniciloricusSpinoloricus (2007)Australoricus (2009)

Nanaloricus mysticus

Higgins larva

mouth cone

scalids

neck

lorica

sensory hairs swimming

appendage

anus

Nanaloricus mysticus

Adult

scalids

mouth

styletsintrovert

neck

anus

lorica

Nanaloricus mysticus

LOCOMOTION

ADULT crawl using their scales and mouth cone

LARVAE use spines and bristles to crawl swim using toes

FOOD CAPTURE and DIGESTIONectoparasites or predators (?)

stylets for piercing and sucking up body fluids of plants and animals

through gut

NERVOUS SYSTEM

well developed brain

nerves

ganglion

REPRODUCTION and DEVELOPMENT separate sexes some are parthenogenetic internal fertilization oviparousshedding and resting stages Higgins larva

- specialized immature form

- pair of oarlike scales called toe for locomotion neoteny

The life history of Rugiloricus. The egg (A); the developing embryo in the egg (B); First instar larva (C); Last instar larva with mature ovary which develops by parthenogenesis and neoteny (D); Cyst larval form with developing larvae inside (E); A neotenous larva (F); Post larva (G); Adult female with ovaries (H1); Adult male with testes (H2).

Life Cycle of Loriciferans

Thank You for listening…

God bless