SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f1ad38233fb7741ac12c02ec31d8e73daeddf04a08d20befe840d16788e926a' 
  AND token = 'v4eypRPqQySTo5hDoZ7u2HrZo9eE5BwIF5F2Lh8ougM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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