SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4369a282b3aa6dd531ef63ed1f220eeeb425d8df88b6455a1f2506b9184713fc' 
  AND token = '+ZmWY/QR50EM3d7rWu3IsW4pq0hM+3+lJNUkL46qTS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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