Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a15f3b53a1d6be4b5ff5254cc3a355e9f4d373cff32e1abdf8028b1f8401932' 
  AND token = 'JfERf0z8Kw+g3oHyjBQMVJvW9N5Ybaeu/PfbJZE6oMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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