SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea68ecea152f30d3183bd495e46a36d4de058818b072029b072b79fdae5dafb0' 
  AND token = 'EBNpRbs+HijQRkf/eXKU1iINu/ewZW7guUh/aYNpG+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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