SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2558869fc9c983cf72b860249ec77557b05024ef5c9364dfd391f6edd72ac72c' 
  AND token = 'eg5i4DtUHmCLfr17QUZKPcVBMMiK7PA4DaAO4nxEXg4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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