SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2a45f7bcecb7cf923f04d8a4ec491932c8d8d0020bb7d9f5a41085091a17363' 
  AND token = 'YyqUH9LQCe/Iv8pRrd4Pw4d7Eqf1IVL+J1jDsXIg/Nw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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