SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '083d591ccccd84d955c581643f642cadc2e3a28c177cc315d7481c9e0a99a82e' 
  AND token = 'AyCc0lq6wA4fwsNseMeOkEQVIsyPyKpYpZRsPmLbrK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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