SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32a9b776825a7de076f084237d7a3ef59460a88556fbad3bb72781df910a3403' 
  AND token = 'fKx7QXfsNjJ6OgUobVAJWxzqaQRu4MdJjnKIe2sRSdo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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