SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfd7572fbe4349e2c69fb13b97892572cd50f09163bf7757f485650ba632a017' 
  AND token = 'fgWHdHsI3wX1FnNqp65RlPUw+uYLzZfj0mVmbMrQbqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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