SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '54e2a811ebf6c8a66a1a65c9a43aafe185bce34355402d95bb103c8aedea6706' 
  AND token = '8mnIgGuxNCJu5VpeuBGYu0V8AavNqXkCLN3DBWkqYzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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