SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '81547a2253f9c55360bd04ae27f095c5d233db8fd17edbbe5cf67e7ce0fafe95' 
  AND token = 'CHLXOviR2eDBLg7sFUX3eEDKTorSHrxwtl6ud1ycHSk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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