SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5830b62c1eeaa88d366b7d09cdca07a6ffe0d3bf8822b18724a57ac1cb95deec' 
  AND token = 'L6GUFAPPFG8hmHQWnie0S2Zvb27QGGTxEAUo2BfOV8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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