SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdca45372cbad1080f455163f35cf7b69dd79af1813549fa845cee53ad2498d5' 
  AND token = 'BbP+8aQZuEj9zYnYvjFy4n6KcTEZ9aywvDAVM8LyWZE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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