SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b2bfac0c921725f1f93b97aa730bbd9c1ad2e706bce5a05426ae3a09404a622f' 
  AND token = 'FwvKclJsL+JFlucLWfnJgjvN9NZHZymO9BwTxqEAA/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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