Table 1.

Collecting information for the 10 species used for this study

Phylum	Species	Class, Order	Collection site	Voucher number	Body part	Preservation
Porifera	Petrosia ficiformis	Demospongiae, Haplosclerida	Punta Santa Anna, Blanes, Girona, Spain	DNA105722*	Entire animal	LN2/-80°C
	Crella elegans	Demospongiae, Poecilosclerida	Tossa de Mar, Girona, Spain	DNA105740*	Entire animal	RNAlater
Nemertea	Cephalothrix hongkongiensis	Anopla, Paleonemertea	Akkeshi, Hokkaido, Japan	DNA106145*	Entire animal	RNAlater
	Cerebratulus marginatus	Anopla, Heteronemertea	False Bay, San Juan Island, Washington, USA	DNA105590*	Entire animal	LN2/-80°C
Mollusca	Chiton olivaceus	Polyplacophora, Chitonida	Tossa de Mar, Girona, Spain	DNA106012*	Entire animal	RNAlater
	Octopus vulgaris	Cephalopoda, Octopoda	Blanes Bay, Blanes, Girona, Spain	DNA106283*	Fragment of arm	RNAlater
Sipuncula	Sipunculus nudus	Sipunculidae	Fort Pierce, Florida, USA	DNA106878*	Distal fragment of animal	LN2/-80°C
Annelida	Hormogaster samnitica	Oligochaeta, Opisthopora	Gello, Toscana, Italy	GEL6**	Distal fragment of animal	RNAlater
Arthropoda	Metasiro americanus	Arachnida, Opiliones	Kingfisher Pond, Savannah, Georgia, USA	DNA101532*	Entire animal	LN2/-80°C
	Alipes grandidieri	Chilopoda, Scolopendromorpha	Tanzania; pet supplier (http://www.kenthebugguy.com)	DNA106771*	Mid part of body	LN2/-80°C

Voucher numbers refer to specimens collected in the same area as the one used for the nucleic extraction, since most of the times the entire animal (or the entire collected piece of animal) was processed. A single asterisk refers to voucher numbers in the Museum of Comparative Zoology, Harvard University, and a double asterisk to those deposited in the Department of Zoology and Physical Anthropology, Universidad Complutense de Madrid. In all cases only one specimen was used for extraction, except for Metasiro americanus, which also had embryos in several developmental stages.