dsn <- "PG:dbname='natural_earth2'
  host='localhost' user='user'"

st_layers(dsn)$name

##  [1] "ne_10m_admin_0_countries"                 
##  [2] "ne_10m_admin_1_states_provinces_shp"      
##  [3] "ne_10m_geography_marine_polys"            
##  [4] "ne_10m_geography_regions_elevation_points"
##  [5] "ne_10m_geography_regions_points"          
##  [6] "ne_10m_geography_regions_polys"           
##  [7] "ne_10m_lakes"                             
##  [8] "ne_10m_land"                              
##  [9] "ne_10m_ocean"                             
## [10] "ne_10m_populated_places"                  
## [11] "ne_10m_rivers_lake_centerlines"           
## [12] "ne_10m_urban_areas"