SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a370ca8fda3e09103d382e319dbe003f22b87782b39a58fae182951150ea4396' 
  AND token = 'iEukrIkKquouoZ9VB+Df0XdxUb7s1A2ZAekf2EoYVhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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