SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '71c423fea4c0f349e291fae03d800653f1d3a84d4e1ad35f95b0a6c43ad6606f' 
  AND token = 'YeLMmpQxOknsW73MIppBb+NSSdKiLIqhLR48ZsR/cC8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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