SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b1d429a17e3284e7127ae1feeebfc35cc67ec5ad3080dce192b36db9bafde33' 
  AND token = 'sW2F22DUenjyImkZS36/PE5jw6ZdzY8iV7bIJKwyrYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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