SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '423ea41dbef2d1097af02a51abff93cfbcfaa18e21f3a4eaaffde9829c8e705f' 
  AND token = 'wtqCxvxR6CqodnVogbWRHNIBKyGwiSZPHdbwvQ2pVrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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