SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0041a69d32c375914ffbafb198b394de7c890a974d0816985885da4e53d0336' 
  AND token = 'POJSizb5dt6Em904sZBqRftREuYPEJXwPMQ06qj0UlA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}