SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a4f45c7fe122b0376f1b33042037a41b682ddd1e2f978fb28c6580d9cd5f505' 
  AND token = 'IFuQpMdh3exJrIFCouo0bCypJ4lkdhqpH6caEYXfYD0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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