SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dbd3b42620c0953c2ee2465b71f80fe7c07fc6cb59b9484529a75b376d4dc5ee' 
  AND token = 'PoM6zP+o5oX8A4v3+luaJyaJMwakOvGjp5VVQnjqwlk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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