SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b62b050353021f476c6075621cc43eea525d50c2561be4583506538435623149' 
  AND token = 'vtlBiOkiEqrJ7h5NplMrPYgPF/YtY7rnKru8k3ZfTjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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