SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6aa31be2ae59213c1800e46c2a6ce491d8869b21e8ec8a5f607586e20b276659' 
  AND token = 'g9LslgOPLzVRWf/xmLSXfAURYKVTAqAfmlHYGBkv0+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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