SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '24c7dc6ae5bf48b07750931fda836ec552932ba5fd60e73de8ce24eccfa30a3c' 
  AND token = 'S8ZLlEph9P3g+jUWRmORBkqnvVgtuD2yyETjfHJg1kU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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