SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1354418782c5a41c81debf10c5ba9d810f2223ed97c4815095e7b40dae7cfa70' 
  AND token = 'ZaNcdCEs1AlRcYvq+6mKq+WUvlZibIwN+UmbH7fA10o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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