SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '360476305fa32389e6dd63cb4d6e88ae0070125ea1b5f2b4c68f9614bcfec7ff' 
  AND token = 'XdLZgIyT8hMZJPiOlUH3Bwzi5koOe2ZD2ckG9dFnQzc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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