SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20011509eebe246192ad02fd365806dddfd6d9ded5ec4ab37f890160479035b7' 
  AND token = 'c8lD4oGypJcknF/DtaB/ALkRNXeP/42t0yJaC/+JO2U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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