The primitive phylum Onychophora (between worm and insect) is particularly important, with at least five species out of a global total of only 200.    From Wordnik.com.  [Greater Blue Mountains Area, Australia] Reference

Nearly half the phyla of animals occur only in the sea (e.g., the sea stars and other echinoderms), whereas only one (the obscure Onychophora, or velvet worms) is restricted to land.    From Wordnik.com.  [Biodiversity] Reference

The hotspot is also home to many species of the phylum Onychophora (velvet worms), a fascinating group of ancient, caterpillar-like animals that are the most primitive group to walk with the body raised up on legs.    From Wordnik.com.  [Biological diversity in Maputaland-Pondoland-Albany] Reference

5. Onychophora.    From Wordnik.com.  [Archive 2006-05-01] Reference

); d Onychophora (Peripatoides aurorbis); e.    From Wordnik.com.  [Pharyngula] Reference

Hemichordata, Nematomorpha, Nemertea, Onychophora, Priapulida, Sipuncula, Echiura, Phoronida.    From Wordnik.com.  [SNAIL'S TALES] Reference

Instead, I will list a compilation of some of the phyla of which I have yet to see a live member: Acanthocephala, Chaetognatha, Gnathostomulida, Hemichordata, Nematomorpha, Nemertea, Onychophora, Priapulida, Sipuncula, Echiura, Phoronida, Loricifera, Pogonophora, Brachiopoda, Placozoa and so on.    From Wordnik.com.  [So many phyla so little time] Reference