SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '078c4f7137353b9e0230b33109021e88105e1879ea77cc894bd759264fba3fd7' 
  AND token = 'fYDU/0hBZS+cvQ2RaNFen4bMrkgVzf5ji1unMw5FZBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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