SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '718c971db3f1d4881dd22d679142776d9a07eb66bce80dc814b041ae0858ac02' 
  AND token = 'oDK8Cc12eVb1RUiqA+gw10FC+HbSBpkMzhjVCLlNUlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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