SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea36afb61e2bc5696d8be6c4bbc239333bba178e48213c119acbdfd08dc6853e' 
  AND token = 'cGSlwThYd+eOhf4WEIgyOhwRy3MmKjwCSGzCPgRPSmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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