SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c059224f7ec7666737755260160ae33c06a10d5ffc8f1fabd8eaaf99b4a6fd8c' 
  AND token = 'BDlUskhPPOCembKdPJxj8u7P+PgADEeVGc+wO62yNEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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