SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '528458e003f564d12664f1c135d6cd9a340454cd3e566c25740c4a6df3fc18ed' 
  AND token = 'AQ24fauoV5irhIumMgOuvhzBK7KRiKN/yjVQbsXvAmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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