SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '733dc1d88eeabcff138baeccba3ea5e3b9cf11b5f2696afb9c85c99acbe69f3e' 
  AND token = '0HuARC9flenrX/Gb0DrSII89gri92Uj5Yksxl4W7vLo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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