SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5448fb766bd8ef227665af53515d9de924c7aa33abccbf39e93b42aefcb7153b' 
  AND token = 'VESkqkG1zszYbShYhXinOldZqKgvnP39XQ4ksW6WkMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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