SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14471c033b6c1c4bae854ba99e6f9682d9a83f2135777a6bb99b233bc92e9d3a' 
  AND token = '5tMAUQaoIvySyTOmTG/leHlaZcP2nNslI5Nr1yxWPUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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