SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34eb535d9c044e16e67bbab8d72d553c23b1edd5573521b801ae822739d04362' 
  AND token = 'g4Sc/fmL/Xn5uyRnogoeax/PzXbdvNSrVqZeVBJsIk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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