SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b1a6a35467d636d2dbb776545864e653158ddcae9a33f1b9bf576c103bc6df1c' 
  AND token = '9YrUi4CN+eCX9TEFZY8WjvHYFqYjpfJTeFSx19wsDiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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