SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9a6457e7f4c5161fa2301b41b46729766c244af5905a68e9ac477182717affce' 
  AND token = '2SqFnHfZMsvuS2uAy65YWdva/jJZD9YAG3+sFS5dj0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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