SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '249ed9280a4821242b8e8db464bb44ed21dc864e506a6a47050dd02015b88778' 
  AND token = 'nbSd14Hug6qDwn7bjOUUJ3MI8b9bT4UlU1YhNyMsfJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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