SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f40d50f95c0bfcb71c20236bd2ff7cc45b4d8200a74ace59f246f03efc550f9' 
  AND token = 'RlhEpPA9bj89GOm4U6jtMsO80JNRqMkDYKSvmhvVJi0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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