SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '60bb3b6bfddcf1e6d1235df791f8820c78c82cb63c3d57dd070da0c49fff0910' 
  AND token = 'VBzQN6+LeWHbAMHDiiCBaTppANMaCVeIUwoyqScyhfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}