SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f30dac3f6f52f97f79f25016b58ca0381f24d3520f2ad86b257c6dcd2f7ce0f' 
  AND token = 'EnGZoU/u62G2HojRcIYdaJA4yQGE8YYYGZBDGiI5PUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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