SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'da387bb48cb77dc35b72f5eed942db2e48aa837e22f3542e66cbb1750e5fd0d7' 
  AND token = 'f307ql1CDyOMDo40vWOslAFcgGFJajyRAgx5tsEP11I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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