SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d43f1f2dec46b33a638cdb89b04c4ce8a2e18e656b96f89a6214773066018ec' 
  AND token = 'm1ugJ9dLgaR/SywGxVrIuEoryHBjf0wiOiFgtv1UUYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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