SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25fa17a5b49354169cf359f17d06328d47bbeb712946e11475b748e6a95e5dd5' 
  AND token = 'oFs8o1HhXVSTa2VDgNdvtQaicBZORNUxQZcyU0Ld0Uo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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