SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '02a8bb2842c1b311b0928f3ce85cb00d6fb1f37bb3d135205d994f1ee32a88ce' 
  AND token = '/JVcWIlk944KlQR2E6wpcxk8b1iy4uolMQWZoyhiEnY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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