SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14a9ee9060a28a2ce0ceb5f8a9263ba7fdad0a225418da183418ba1f9097d2ad' 
  AND token = 'LAD5V5Sub080w3W2Dde5POQSuxRKj4fzFcJG6DxwT0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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