Results

General

The importance of digitized worldwide available data for the future development of taxonomy was just recently emphasized (Godfray 2002a, b). The Orthoptera are one of the few insect groups for which complete digital registers of valid taxa exist (Orthoptera Species File Online:OSF). Nevertheless, much of the information stored within museum collections is still not readily accessible, because most of it is not digitized (Lampe & Riede 2001).

DORSA (abbreviation for Deutsche Orthopteren- Sammlungen = German Orthoptera Collections) housed at the Zoologisches Forschungsinstitut und Museum Alexander Koenig Bonn (ZFMK) is part of EDIS, the Entomological Data and Information System launched by the German Federal Ministry of Education and Research (BMBF).

EDISis intended to provide access to relevant information about insects and other arthropods for research and the general public and to promote digitization of the data scattered over various entomological collections in Germany in a comprehensive database, the SYSTAX database at the University Ulm.

The aim of DORSA is the database access to important Orthoptera (grasshoppers, katydids and crickets) specimens in German research collections including multimedia information as pictures and sounds, and an internet-link to the global species database Orthoptera Species File (OSF).

All information in DORSA is specimen based. It is thus possible to reproduce where single specimens have been collected, how they looked like, what was their stridulation etc. DORSA is thus complementary to the Orthoptera Species File where the taxonomic background and general information on the species can be found. In more detail, DORSA covers the following points:

Registration of type specimens

Registration of type specimens was done in the major German natural history museums that hold large Orthoptera collections (ZMB Berlin, DEI Eberswalde, SMTD Dresden, ZSMH Hamburg, MLUH Halle, ZFMK Bonn, SMF Frankfurt, SMNS Stuttgart, ZSM Munich).

The Zoological Museum of the Humboldt-University Berlin houses by far the greatest number of Orthoptera types. The aim of specimen registration is a type catalogue of the Orthoptera housed in German collections and to verify the corresponding information in the Orthoptera Species File Online (above) which is the taxonomic backbone for our database. Compiling the specimen information in the museums (Tab. 1-3) covered all primary types, most of the paratypes, additional specimens on which taxonomic revisions were based and voucher specimens for which sound recordings are available. We started with the information given in the Orthoptera Species File (OSF) [version April 2000] which contained information on primary types compiled from published data (presumption in Tab. 1). With this information we checked what is actually housed in the museum collections (museum data). It followed a validity check. In case of disagreement between the information in OSF and the actual museum data, it was necessary to consult the original publications. Finally the databases were updated as was done with the specimen information in the museums when necessary. After the validity check, the inventory data are imported into the all-biology database SYSTAX. In this database, interested users can find the specimen information together with specimen based multimedia data (images and sounds). Moreover, DORSA is linked on a species to species level with OSF2 thus that additional taxonomic information, synonyms, references, will be available by a link from DORSA to OSF, while when searching OSF it will be possible to find specimens and their media data in DORSA.

Table 1. Registration of type specimens of Orthoptera without Tridactyloidea in German museum collections by February 2004.

Collaborating museums: ZMB Berlin, DEI Eberswalde, SMTD Dresden, ZSMH Hamburg, MLUH Halle, ZFMK Bonn, SMF Frankfurt, SMNS Stuttgart, ZSM München.

	presumption	museum data
museum	taxa with primary types in OSF*	taxa with primary types checked	taxa with types including paratypes	number of type specimens	total recorded species	total recorded specimens
Berlin	1115	1502	1916	5418	2207	6320
Eberswalde	47	73	140	408	164	445
Dresden	66	118	167	511	279	856
Hamburg	144	190	269	435	324	553
Halle	39	55	55	75	91	151
Bonn	6	43	50	166	89	274
Frankfurt	82	151	179	334	273	553
Stuttgart	47	110	129	599	147	658
München	27	53	84	232	101	382
Sum1	1573	2295	29891	8178	36751	10192
Voucher-Specimens for sound records		66	160	673	866	5788
Sum1		2309	29351	8851	40571	15980

¹settled [species with specimens in several collections are counted only once]

Table 2. Validity check of DORSA type specimen registration compared with OSF data at the starting point of DORSA (April 2000).

	validity check
museum	type data in OSF not confirmed in museum	primary types lost (taxa)	primary types not formerly listed in OSF	no taxon entry formerly found in OSF	unlabeled, newly recognized primary types
Berlin	136		143	68	12
Eberswalde		1	25
Dresden	6		56	10	7
Hamburg	5	57	47	1
Halle	5		26	4	16
Bonn			14	13
Frankfurt			69	5	2
Stuttgart			69	5	3
München		1	21	1
Sum	152	59	470	107	40

Table 3. Registration of Orthoptera types from different taxonomic subgroups (as of February 2004).

taxonomic group	taxa with primary types checked 1	taxa with types including paratypes 1	number of type specimens	total recorded species 1	total recorded specimens
Tettigonioidea	701	853	2378	1413	7051
Stenopelmatoidea	168	171	260	250	563
Grylloidea	283	315	819	511	1675
Acridomorpha	960	1351	4786	1506	5428
Tetrigoidea	187	224	564	352	1176
Tridactyloidea2	7	14	34	15	37

¹ settled [species with specimens in several collections are counted only once]

²without specimens of ZMB Berlin

Comparison

To view the specimens registration in an international frame, the number of type specimens in German collections was compared with the number of described taxa worldwide. The number of described taxa was compiled from OSF2 at 23.III.2003. The number of species group taxa (species, subspecies, synonyms, extant taxa only) accounts for 28876 names for all Orthoptera (Tettigonioidea 7500, Stenopelmatoidea 1724, Grylloidea 4637, Tetrigoidea 1537, Acridomorpha 13122, Tridactyloidea 356). For about one tenth of those names, type specimens exist in German collections: depending on the taxonomic group, for 6–14 % primary types or for 7–17 % any types including paratypes (Figs 1-2). The relative number of types is highest in Tetrigoidea with 14% and lowest in Grylloidea with 6% of the primary types. In absolute numbers, most type specimens belong to Acridomorpha.

Figure 1. Types of Orthoptera species in German museum collections sorted by taxonomic group. [From Ingrisch et al. 2004a].

Figure 2. Species group names of Orthoptera worldwide (valid names and synonyms) and types specimens in German collections. The category holotype includes also syntypes, lectotypes and neotypes. [From Ingrisch et al. 2004a].

Photographic and acoustic documentation

The aim was to create a "virtual museum" that documents the type specimens and helps to reduce the inquiries about and the loan of type material. Most type specimens are documented by photographs. In total, more than 30000 images have been taken. Photographic documentation includes full specimen labels, general habitus of the specimens, details of diagnostic characters, and also genital structures if this did not require extra manipulation of the specimens. The images are provided with size scales. All media data are linked to a specific specimen. Full documentation is available in SYSTAX.

Sound recordings of Orthoptera were usually done by private researchers and were not previously compiled in a public sound archive. DORSA establishes the first comprehensive public sound library for Orthoptera sounds in Germany, and makes them available on the internet. More than 12000 recordings were compiled that are linked with known individual specimens. They were contributed by H. Braun, K.-G. Heller, S. Ingrisch, F. Nischk, K. Riede and G.H. Schmidt; others will follow. The sound library is the base for the development of software for automatic song recognition.

Automatic song recognition

Based on the DORSA song database, a rapid assessment tool is developed for automated song recognition (Dietrich et al. 2002). In principle, automatic song recognition in crickets (Grylloidea) and katydids (Tettigonioidea) follows the scheme:

1. pre-processing and filtering of the raw time signals (Fig. 3), 2. segmentation of the filtered signals into single pulses (Fig. 3), 3. extraction of typical features of pulses or pulse series, 4. automated classification in local time windows (Fig. 2), 5. application of classifier fusion:

a) to combine the classifier outputs of different features, b) for temporal fusion of classifier outputs (Fig. 4). To train the neural network architecture successfully a data set of known taxa is needed. For that as many as possible songs of different individuals of the same species should be used. At present the tool for the automatic sound recognition runs properly with a set of 215 songs from 137 individuals of 30 cricket species (for details in see Palm & Dietrich 2001).

Figure 3. Characters most suitable for the classification of cricket songs are the distances between pulses, the duration of pulses, and the frequency course within pulses. The feature vectors are classified individually and the results of the single classifiers are combined through classifier fusion. [From Ingrisch et al. 2004b].

Figure 4. Fusion of characters utilizing multiple decision templates (MDT). [From Ingrisch et al. 2004b].

Geographic information

It is often difficult to find the exact locality for classical specimens as old types. The information given on labels may be either not precise or the names of places or their affiliation to countries has changed since the time of collection. Fortunately there are several expedition reports to allow tracing the localities with sufficient precision. For all specimens with the locality information sufficiently reliable, we geo-referenced the collection sites with latitude/longitude co-ordinates (3100 out of the roughly 5500 locality data). This will help future users to find this information easily, and it allows mapping by a geographical information system (GIS). In the GIS the distribution of specimens or taxa can be overlaid with additional information such as environmental data. Such applications run already over the word wide web using Open GIStechnology. In cooperation with the Institute for Geography of the University of Bonn (GIUB)we mapped the DORSA locality data on an Open GIS server >> Dorsa Map Server

The evaluation of the locality data may reveal interesting results even without geo-referencing. For almost all types there exist at least some basic information on the country of origin which allowed to calculate the number of type specimens for each country of origin (Riede et al. 2004; Fig. 5). By that way DORSA helped to uncover basic taxonomic information formerly hidden in specialized publications of in museum collections. Part of the types from tropical countries represent unique specimens of taxa that might be already extinct. Natural history collections housing type specimens should thus be regarded as belong to our worlds cultural heritage.

Figure 5. Countries of origin of Orthopteran type specimens (including paratypes) in German museum collections. [From Riede et al. 2004].

Linking DORSA with OSF

The worldwide name register "Orthoptera Species File" (OSF) is the taxonomic reference for DORSA. A unique species ID was introduced in OSF by D. Eades that allows species specific links between OSF and other databases. DORSA is linked to OSF on a species to species basis. The actual taxonomic status of the taxa included in DORSA can thus be checked using the link to OSF. While in OSF it is possible to find specimens included in DORSA and open the corresponding information by a link to SYSTAX.

Sumup of data recorded by DORSA to the eND of 2003

• Specimen records (including voucher specimens): 15980.
• Species records: 4057.
• Locality records: 5810 (geo-referenced: 3176).
• Number of images documenting type specimens: 30446.
• Number of sound files or wing movement files: 11924.

Links to the Data provided by DORSA

Specimen Data and Images

Orthoptera Sounds

DORSA Interactive Map Server

Cricket Specimens and Images

DORSA Homepage

Acknowledgements

From April 2000 to March 2003, DORSA was funded by the German Federal Ministry of Education and Research (BMBF). Our special thanks go to the curators of the museums mentioned above for their cooperation when digitizing the specimen data. D. Eades (Illinois Natural History Survey) cooperated with linking of DORSA to OSF.

References

Dietrich, C., Schwenker, F. & Palm, G. 2002. Decision Templates for the classification of Bioacoustic Time Series. Proceedings of IEEE Workshop on Neural Networks and Signal Processing, p. 159-168, Martigny.

Godfray, H. C. J. 2002a. Challenges for taxonomy. Nature, 417: 17-19.

Godfray, H. C. J. 2002b. How might more systematics be funded? Antenna, 26 (1): 11-17. pdf

Ingrisch, S., Riede, K. & Lampe, K.-H. 2004a. Deutsche Orthopterensammlungen - virtuell. – Mitteilungen der Deutschen Gesellschaft für allgemeine und angewandte Entomologie 15 [2003]: 479–482.

Ingrisch, S., Riede, K., Lampe, K.-H. & Dietrich, C. 2004b. DORSA - A "Virtual Museum" of German Orthoptera Collections. – Memorie Soc. Entomol. Ital., 82 (2003): 347-354.

Lampe, K.-H. & Riede, K. 2001. An information infrastructure for German insect collections including multimedia and GIS Tools. Pp. 43-48 in: Saarenmaa H. & Nielsen E.S. (eds), Towards a global biological information infrastructure: Challenges, opportunities, synergies, and the role of entomology. Technical Report 70, European Environment Agency, Copenhagen. pdf

Palm, G. & Dietrich, C. 2001. Automated Identification of Bioacoustic Signals, Biolog Statusseminar, Bonn, (foils in pdf format)

Riede, K. , Lampe, K.-H. & S. Ingrisch 2004. Deutsche Orthopterensammlungen (DORSA). Aufbau eines virtuellen Museums. - Verhandlungen Westdeutscher Entomologentag 2002, Löbbecke Museum, Düsseldorf, S. 63-70.

Further References