SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '99a28b724dd72c052b75355def03293a51e11900dbc406e9a710cc5f84e0fba2' 
  AND token = 'QcYuufWpRM2Fqt79eaJqk35hdR8S6NcDlGwiMCeiOYg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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