Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '5d25ff72069ccd7ca81a8e713c0da257d0f279815ad5d04a9e01b120342ed784' 
  AND token = '0LBQHQRiArKkaLUL2couYwqQbRLFttPK2B2sVwZKrIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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