SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1577f42892ef0a6b1ea70bb85423e74ecd5ac8e1fe3339c5192a321d19e1178f' 
  AND token = 'W9yrDzOlvy/wGhDwFjPkuB2bl3VY25SgIRMGoH5PLBw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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