Cover picture: Rocky coastline, the region where the sea, the continent and the atmosphere interact and exchange matter and energy (Photo: Roberto Calderón).

Cover picture: Sea anemones on Macrocystis pyrifera blades and pneumatocysts (Photo: Roberto Calderón).

Cover picture: Fish with skin colors that camouflage a colorful environment (Photo: Roberto Calderón).

Cover picture: A young Galapagos fur seal, Arctocephalus galapagoensis, found in La Escobilla community, Oaxaca, Mexico (Photo: Carlos Javier Tamayo Millán; see Tamayo-Millán et al. this issue).

Cover picture: Vibrant rocky shore with agitated blue seawater and seagulls resting and taking flight over the rocks (Ensenada, Baja California, Mexico) (Photo: Melba De Jesús Huerta).

Cover picture: Close-up of small wave breaking on a rock covered by algae (Photo: Claudia Michel-Villalobos).

Cover picture: A close-up of the spines of a red urchin (Mesocentrotus franciscanus), taken at ~20 m depth on Calvert Island, British Columbia, Canada. Red urchins are generally known as a nearshore species and are associated with kelp forests or rocky reefs. This is one of the few species that spans its distribution along the entire northeastern Pacific, from Alaska (USA) to Baja California (Mexico), and it is thus considered a marine resource shared by 3 nations that demands international attention for its ecological and economic relevance (Photo: Aaron Galloway).

Cover picture: Acanthophora spicifera overgrowing among Pocillopora and Porites coral colonies off Point Roca el Caimancito, La Paz, Baja California Sur, Mexico (Schnoller et al. this issue).

Cover picture: Free-ranging sea turtle, Chelonia mydas (Veracruz, Mexico) (Photo: Amelly Hyldaí Ramos Díaz).

Cover picture: Banded guitarfish (Zapteryx exasperata) at 18-m depth in waters off Isla San Martín (San Quintín, Baja California, Mexico) (Photo: Roberto Calderón).

Cover picture: California sea lion, Zalophus californianus, colony at Los Islotes, La Paz Bay, Baja California Sur (Mexico), during the breeding season (photo: Claudia Janetl Hernández-Camacho).

Cover picture: Fish and sea urchins about the seaweed Ecklonia sp. (photo: Roberto Calderón).

Cover picture: Tide pool in a rocky intertidal zone in Ensenada, Baja California (Mexico) (photo: Gerardo Ybáñez-Gómez).

Cover picture: Fish swimming in a kelp forest (photo: Roberto Calderón).

Cover picture: Magnified view of the second gill arch of juvenile yellowtail Seriola dorsalis associated with Amyloodinium ocellatum (Del Río-Zaragoza et al. this issue).

Cover picture: Cystoseira algae samples from the coast of Tunisia (Bouafif et al. this issue).

Cover picture: Histological images of Mustelus henlei female (outer) and male (center) gonads (Soto-López et al. this issue).