SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd382f01f01d783bae4aa47c9cf1d0109dd3557785e225d116ccfe7a76220549' 
  AND token = 'J2pKVRxRXOM3fX+xIRxVFLHB1rL4rGBkqEET1JH1MNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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