153j. c. fabricius and acesta excavata

Steenstrupia Sneli, J.-A., J. Knudsen & A. Vedelsby. Johan Christian Fabricius and his molluscan species, Acesta excavata (J. C. Fabricius, 1779). – Steenstrupia 30 (2): 153–162. Copenhagen, Denmark. April 2009. ISSN 0375-2909.

Johan Christian Fabricius (1745–1808) is one of the most important Danish natural historians and scientists and is regarded as Carl von Linné’s best pupil. He published many books on systematics and described more than 1000 new species during his lifetime. He is probably best known today for revolutionizing the systematics of insects by using their mouthparts as a taxonomic tool in the species description. In 1778 he undertook a remarkable three-month field trip to the southern part of Norway. Throughout the journey he collected and made notes about the mammals, birds, fishes, insects, and marine invertebrates he encountered. Among the latter was the large bivalve now known as Acesta exca-vata. His book, Travels in Norway, containing original descriptions has provided a solid foundation for later scientists working on the fauna of Norway. This paper gives a brief description of J. C. Fabricius’ life and details of the journey. In particular it describes Fabricius’ interest in conchology and attempts to unravel the intriguing history behind the describing of Acesta excavata. The possible whereabouts and provenance of the specimens on which he based his description are also discussed.

Keywords: J. C. Fabricius, Acesta excavata, Bivalvia, historical malacology

Jon-Arne Sneli: Norwegian University of Science and Technology, Trondhjem Biological Station, NO-7491 Trondheim, Norway. E-mail: jon.sneli@bio.ntnu.no

Jørgen Knudsen & Antonia Vedelsby: Zoological Museum, University of Copenhagen, Universitets -parken 15, DK-2100 Copenhagen Ø, Denmark. E-mail: alvedelsby@snm.ku.dk

Steenstrupia 30 (2): 153–162.

Johan Christian Fabricius and his molluscan species, Acesta excavata (J. C. Fabricius, 1779)JON-ARNE SNELI, JØRGEN KNUDSEN & ANTONIA VEDELSBY

INTRODUCTION

The great Lima-shell, Acesta excavata (J. C. Fabricius, 1779) is a very common species along the Norwegian coast on steep, rocky bottoms in depths from about 100 m downwards and is a conspicuous inhabitant of the fjords in western Norway (Fig. 1). In the Trondheimsfjord this Lima-shell is often associated with the presence of soft corals like Paragorgia arborea (L., 1758) and Primnoa resedaeformis and the stone coral Lophelia pertusa (L., 1758). Because of the so-called “fjord-effect” the species occurs from about 40 m downwards in the fjord, in much shallower waters than along the open coast. In the Trond heimsfjord specimens more than 100 years old have been collected (Elvestrand 2007).

It is surprising that the species was not de-scribed by Johan Ernst Gunnerus, Bishop of the Trondheim area, Nidaros and northern Norway

during the period from 1758 to 1773 when he was collecting. Gunnerus described about 20 species of plants and animals during these 15 years, among them the horny coral Primnoa resedaeformis and the starfish Stylaster norvegi-cus, which are found in the fjord in the same habitat as A. excavata (Gunnerus 1763). Instead, A. excavata was described as Ostrea excavata by a Dane, Johan Christian Fabricius, during a journey through southern Norway in 1778. We have attempted to locate the history and where-abouts of the specimens on which he based his description.

The surname Fabricius is attached to two unrelated Danish naturalists, Otto Fabricius (1744–1822) and Johan Christian Fabricius (1745–1808). Otto Fabricius was a great admirer of the “Apostle of Greenland”, Hans Egede. As

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a result of this admiration for Egede he decided to become a clergyman so that he could work as a missionary in Geenland. In 1768 he obtained a position as a missionary in Frederikshaab and before leaving Denmark he was urged by Count Otto Thott, a man with a great interest in natural history, as well as by the famous Otto Fridrich Müller (1730–1784) to do reseach and collect natural history specimens. The results of his collecting in Greenland were published in his book Fauna Groenlandica in 1780. Because of this publication, Otto Fabricius is better known among marine biologists than J. C. Fabricius. However, in general the latter is the more highly regarded biologist.

LIFE OF J. C. FABRICIUS

Johan Christian Fabricius (Fig. 2) was born on the 7th of January 1745 in Tønder, Denmark where

his father worked as a physician. His interest in natural history started in his early years, prob-ably encouraged by his father. As a young boy he was already an eager reader of Linné’s books Species Plantarum and Philo sophia Botanica (Collin 1891). Fabricius began his studies at the University of Copenhagen in 1762, but later that year he went to Uppsala to study under Carl von Linné. Two years later, in 1764, he returned to Copenhagen and with Linn aean enthusiasm began writing his book Systema Entomologicae which was published after 11 years, in 1775.

During these 11 years (1764 to 1775) Fabri-cius had very little money and suffered great hard ship. In 1768 his father, who by then had obtained a good position as Medical Director at Frederik’s Hospital in Copenhagen, managed to have him appointed as Professor of Economics at the Natural Theatre at Charlottenborg, one of the forerunners of the Zoological Museum at the University of Copenhagen (Wolff 1999).

In the 18th century an overwhelming number of newly recognized plants and animals made the establishment of collections of all sorts of natural objects a fashion amongst the upper classes. The University of Copenhagen strongly opposed the new fashion and in 1757, as a countermove, Count Adam G. Moltke established a self-supporting college, Natural- og Husholdnings-Cabinettet (The Naturalia and Housekeeping Collections, later becoming the Natural Theatre) at Charlot-tenborg in Copenhagen. In addition to teaching, the main task was to build up the scientific collec-tions. In 1772 the collections were transferred to the University of Copen hagen (Wolff 1999). At the time Fabricius got his position as professor of these collections he was studying in London. However, he managed to postpone the Charlot-tenborg appointment for two years while he con-tinued to study at several universities in Europe. He returned to Copen hagen in 1770 to discover that the Natural Theatre was to become part of the University of Copenhagen and that his pro-fessorship had been transferred to the University where his salary would be less and there were no extra benefits. Fabricius, therefore, still needed support from his father. This support continued until 1775 when his father died; this was the same year Fabricius managed to publish his Systema Entomologicae.

Fig. 1. Acesta excavata (J. C. Fabricius, 1779). Illus tration: Antonia Vedelsby.

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he needed and he became more and more dis-satisfied with his working conditions. Fabricius tried to give in his notice three times. In 1792 he applied for a better position in Düs ternbrook as Director of a Botanical Nursery. When he was passed over in favour of a young man who could not separate “a cabbage from an apple tree”, he resigned his Kiel post. However, the students in Kiel applied to the King and to Fabricius himself to withdraw his resignation, and he let himself be persuaded – obviously he must have been a very good teacher.

The expedition to Norway in 1778

Despite all his difficulties at the University of Kiel there were some advantages; in particular he had opportunities to travel, often funded by his institution. In 1778 one of his study tours went to Norway. Throughout the trip he made detailed notes and all samples were carefully annotated so that, in 1779, he published the results of his travels in his book Reise nach Norwegen mit Bemerkungen aus der Naturhistorie und Oekon-omie (Travelling in Norway with comments on its natural history and economy). This three month expedition was unique for those times and amass-ed a wealth of scientific information (Fig. 3).

Fig. 2. Johan Christian Fabricius (1745–1808). Unknown illustrator.

Fig. 3. Travelling in Norway in the 18th Century could be exhausting on narrow, bad roads. Drawing by J. W. Edy (1800).

The University in Kiel found Fabricius’ tech-nical knowledge very useful and in 1776 offered him a position as Professor of Natural History and Economics. The University pro mised him they would build a Natural History Museum and a Botanical Garden. This promise was never fulfilled. Nor did he get the teaching equipment

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His expedition started in Copenhagen on the 7th of June 1778. He passed the Sound and went up through the western part of Sweden and pass-ed the border at Svinesund on the 16th of June. He stopped to sample in Fredrikstad and Moss, mostly collecting insects and plants. Before he took the ferry across the Oslofjord to Horten he made a short trip to the littoral zone at Moss, sampling amphipods of the genus Gammarus, the shore crab Carcinus maenas (L., 1758) and some macroalgae. From Horten he visited Tønsberg (20th of June), Larvik, Kongsberg (25th of June) and Drammen, reaching Oslo on the 1st of July. On the 4th of July he visited Eidsvoll and then went eastwards to the river Glomma which he followed northwards, reaching Røros on the 11th of July. From here he travelled along the river

Gaula to Trondheim, arriving on the 18th of July. This first part of the journey included terrestrial and limnic areas where he sampled mainly in-sects and plants (see Fig. 4).

Even though his friend, Bishop Johan Ernst Gunnerus was dead by 1773 (1718–1773), Fab-ricius was keen to see some of the material Gun-nerus had managed to collect and describe (see among others, Gunnerus 1767, 1768). He visited the Library of the Royal Norwegian Society of Sciences and Letters and also their Natural History Collection. He does not give a general impression on the condition of the exhibits, but in 1799, in a travel book by the Englishman Edward Daniel Clarke, Clarke writes that “at the end of the Library there is a Museum, a square formed room filled with objects of antiquity, minerals, plants, and animals. Opposite the entrance there is a box of glass containing a well preserved hu-man body. The skin is removed to show all body muscles”. Fabricius lists some of the marine ani-mals which were present in the Museum: corals, lobster, and gammarids (e.g., Gammarus esca).

On the 21th of July he visited Munkholmen, an island close to Trondheim harbour which was used as a prison and fortress, here he found lugworms (Arenicola marina (L., 1758)), the two amphipods Gammarus locusta (L., 1758) and Corophium volutator (Pallas, 1766), as well as the Moon jellyfish Aurelia aurita (L., 1758). In the morning of the next day (22th of July) he left Trondheim. On sailing out of the Trondheims-fjord he encountered one low pressure after an-other. The weather became really bad with heavy rain, gale force winds and stormy seas and he had to stop at Ørland, in the outer part of the fjord. Ørland is a very flat area exposed to bad weather and he was weather-bound here for about a week before the sea calmed down and he was able to reach Kristiansund on the 28th of July. At Ørland the littoral zone is extensive so, even though large waves rolled ashore, he could still sample a few animals from the upper limit of the littoral: the polychaete Phyllodoce maculata (L., 1767), the amphipod Gammarus locusta, the shore crab Carcinus maenas, and the chitons Tonicella ru-bra (L., 1767) and Stenocemus albus (L., 1767). Today this littoral zone and the sea area surround-ing it is a nature conservation area.

The stormy weather seemed to follow him,

Fig. 4. Map of southern Norway showing the route travelled by Fabricius.

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Fig. 5. Page with drawings of marine animals observed and described by Hans Strøm (1762). Among others, the parasitic copepod Lernaeocera branchialis and the pycnogonid Pycnogonum littorale can be seen.

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but despite this, after a few days he managed to travel from Kristiansund south to Volda where he arrived on the 4th of August. Here he met up with the Reverend Hans Strøm (1726–1797) who had written the book Sundmørs beskrivelse (A Natu ral History of Sunnmøre, 1762). In the book Strøm describes the parasitic copepod Ler-naeocera branchialis, the prosobranch whelk Trophon truncatus and the sea spider Pycno-gonum littorale among other species (Fig. 5). As the weather was still bad Fabricius had to stay with Strøm until the 7th of August; however, this enabled him to see P. littorale in its natural habi-tat, as well as many other littoral animals.

Eventually the weather improved and Fab-ricius was able to travel via the Nordfjord and the Sognesjø to Bergen where he arrived on the 14th of August. Bergen at that time had a population of about 2000 and Fabricius called it “the biggest and most important city of Norway”. Among other people in Bergen he visited the dispensing chemist Mr Johan Carl de Besche (misspelt by Fabricius as “Debeche”, 1737–1787) who ran a pharmacy called Svaneapoteket [the Swan Phar-macy, see no.wikipedia.org/wiki/Svaneapoteket i Bergen]. In his youth de Besche had been sent by his father to Uppsala to learn about plants and the use of herbs from Linné so that he could use his knowledge in the pharmacy (see article in Wikipedia). To this end de Besche had laid out a garden full of medical herbs. Fabricius describes in his book (p. 377) a visit to this lovely garden that later became well known in Bergen as the “Maartmann Garden” (Moe 1988). De Besche also had an interesting natural history collec-tion from which Fabricius was shown two large valves of the bivalve Lima sampled in the area outside Bergen. De Besche had even kept the soft parts in alcohol in a jar besides the two shells. On page 368 and 369 in his book (1779) Fabricius gives a very concise description of the species which he calls Ostrea excavata:

Ostrea Excavata testa aequivalvi gibba, mar-gine erecto: medio obliquo impresso. Habitat in oceano Norvegico. Testa magna cardinis fossula transversa atra, nitida. Margo introrsum eleuatus ad angulum rectum cum testa, in medio fovea lata oblique versus apicem sensim attenuata impressa.

In Bergen Fabricius also met Mr Arent Jansen

Greve (1733–1808) who, after settling in Bergen as a goldsmith in 1764, established a collection of insects, molluscs, and minerals. He corresponded with Martin Vahl (1749–1804) and O. F. Müller (Ingstad 1943). In his book Fabricius mentions the horny coral Gorgonia lepadifera (= Primnoa resaedaformis Gunnerus, 1763), the feather-duster worm Sabella penicillus L.,1767, the serpulid worm Madrepora cellulosae (= Hydro-ides norvegica Gunnerus, 1768), the bryozoan Flustra pilosa (Electra pilosa L., 1767), the tooth shell Dentalium entale (Antalis entalis L., 1758), the sea cucumber Holothuria pentactes (= Holothuria frondosa Gunnerus, 1767), and the sea squirt Ascidia virens (= Ciona intestinalis L., 1758), which he saw in Mr Greve’s collection (Fabricius 1779). In his book he described some of these species as new to science: the squat lobster Pagurus rugosus (now Munida rugosa), and the serpulid worm Serpula tridentata (now Placostegus tridentata).

On the 20th of August Fabricius left Bergen and Norway on a boat to Copenhagen and Kiel and ar-rived back home on the 4th of September. By then he had been travelling for nearly three months, an amazing achievement for those days.

Results of the journey and the Lima shell conundrum

Even though the part of his journey that went along the Norwegian west coast was affected by bad weather, his book (1779) contains many important notes not only on terrestrial plants, animals and birds, but also on marine flora and fauna (Fig. 6). His total list contained the follow-ing number of species: 2 mammals (lemming, field mouse); 12 birds; 20 fishes (Gobius flav-escens (two-spotted goby) as a new species); 100 insects; 77 other invertebrates.

Many of the insects that Fabricius sampled during his travel in Norway he described as spe-cies new to science. The large Lima shell from the chemist de Besche’s collection in Bergen, Ostrea [Acesta] excavata, that he described as new is often thought to have been described by the other Fabricius, Otto Fabricius, of Greenland so it is very important to differentiate between the two men. As mentioned earlier, Johan Christian

159j. c. fabricius and acesta excavata

Fabricius was the most important Danish pupil of Carl von Linné and he was also a far more important scientist than Otto Fabricius. Johan Christian Fabricius’ close contact with Linné had given him excellent knowledge of both botany and zoology and he used this knowledge widely. For instance, he revolutionised the systematics of insects by using the mouthparts in the species de-scriptions. He published many books on insects: Systema Entomologiae, Genera Insectorum, Spe-cies Insectorum and Mantissa Insectorum and he brought a large collection of insects, many of them type specimens, back to the museums in Copenhagen and Kiel.

The species list published by Fabricius in his book of 1779, together with the publications of Gunnerus and Strøm (Broch 1954) and the Dane O. F. Müller (1779), were the first thorough and extensive bodies of information on the flora and

fauna of Norway. All of this information was published within a period of 30 years.

The problem of provenance

But the question we are asking is: did Fabricius bring a type specimen of Acesta excavata from the de Besche collection back to the Zoological Museum in Copenhagen?

There is no mention in Fabricius’ book of 1779 that de Besche offered him one (or both) of the two specimens that he had in his collection. Nor is there any suggestion that he managed to get specimens from other naturalists in Bergen. We also find it strange that there were no Lima shells present in the Museum that Gunnerus had set up in Trondheim in the 1760s and which Fabricius visited long before visiting Bergen. Since the species is very common in the Trondheimsfjord today, we had expected it to have been so 250 years ago.

Fabricius corresponded with many foreign conchologists. Among them was Johann Samuel Schröter (1735–1808) who worked in Weimar and Buttstädt. Schröter was the editor of Journal für die Liebhaber des Steinreichs und der Kon-kyliologie from 1774 to 1780 (Fig. 7). This was in fact the first journal of conchology to be pub-lished. To make the information on the Acesta excavata more broadly known, Fabricius com-municated, via the Journal, the description that he had made in his book (1779, p. 368–369) of the large bivalve, Ostrea excavata, having seen "live" specimens in Bergen (although it was not strictly true to say Fabricius had seen live speci-mens). This large bivalve, attaining a length of 20 cm and living in depths of 50 to 100 m or more was, at the time of its discovery, considered very rare (Schröter 1782).

In 1782 Schröter published an article in Für die Litteratur und der Kenntniss der Naturge-schichte sonderlich der Conchylien und der Steine, volume 2, page 117 to 128: “Von der Ostrea excavata des Fabricius, und ihrem Be-wohner”, where he writes: “Ich war so glücklich von zwey Freunden zu Bergen in Norwegen zwey Exemplaren von der Ostrea excavata mit Thier in Wiengeist zu erhalten. Der Name Ostrea exca-vata kommt von dem Herrn Professor Fabricius

Fig. 6. Front page of the book Travel in Norway by J. C. Fabricius, 1779.

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in Kopenhagen her, welcher diese Muscheln in seiner Norwegischen Reise S. 368 beschrieben, und also genennt hat.” [From friends in Bergen I was so fortunate to receive two specimens of Ostrea excavata [Acesta excavata] in alcohol, both with soft parts. The name Ostrea excavata is from Mr Professor Fabricius in Copenhagen who on page 368 described and gave name to this bivalve in his book Travelling in Norway, 1779.] But Schröter himself gives neither a figure of the species nor refers to one. Neither does he refer to any correspondence with Fabricius in which Fabricius mentions that specimens of this large Lima shell are kept in the museum collections in Copenhagen.

In the Molluscan collections of the Zoological Museum today there are two specimens labelled, cleaned and polished by Lorentz Spengler (1720–1807) in the same way that he usually treated his specimens. The label has no sampling date but the locality on the label is “Drontheim” (Trond heim) and not Bergen.

In volume 7 (1784) of the Neues system-atisches Conchylien-Cabinet Chemnitz (1730–1800) illustrates the species Acesta excavata of Fabricius (Fig. 8). On page 355–356 of volume 7 Chemnitz writes that the two specimens that he used to illustrate Acesta excavata were his own and one specimen belonging to Spengler; he also states that the valves are kept in the “Musei Spengleriana et Nostro” (the private collections of Spengler and Chemnitz’ own one). Chemnitz gives no written statement that he received his own specimen as a gift from Fabricius. Chemnitz (1784) describes the species as “very uncommon, with a rather large size, beautiful shape and nice ornamentation. In the middle of the cardinal area there is a hollow, somewhat like what can be seen on oyster species. Mr. Fabricius called the species “excavata”, a shell which is hollowed out. On my specimen I can see not only many ribs but also concentric growth lines. The species lives along the Norwegian beaches. My specimen measures 4 zoll 10 lines long, 3 zoll 6 lines broad. The Spengler duplicate found near Trondheim, meas-ures 5 zoll 3 lines long, 3 zoll 10 lines broad. In the Spengler collection a valve is also present that is a brilliant white like the whitest ivory” [translated from the German].

By modern standards the specimen belonging to Chemnitz measured 11.4 cm in length and 8.3 cm broad, and the specimen belonging to Spengler, 12.4 cm long and 9.0 cm broad (two rather small shells, as the maximum length is up to 20 cm). The smallest valve in the Spengler collection in the Zoological Museum is nicely polished. Unfortunately the measurements given by Chemnitz do not quite fit this specimen as the shell is 10.4 cm long and 8.0 cm broad. The other shell that could have been used by Chemnitz to illustrate measured 13.9 cm in length and 10.1 cm broad. Maybe, due to the imprecise comparisons between zoll, lines and cm [1 zoll = 2.3599 cm, 1 line = 1.9665 mm and there are 12 lines to 1 zoll], the Spengler specimens and the specimens

Fig. 7. Front page of the world’s first journal of chonchol-ogy, Journal für die Liebhaber des Steinreichs und der Kon-chyliologie, which started in 1774.

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referred to by Chemnitz could be one and the same and are the shells we see today. However, for the moment this can only be speculation.

So, if we are looking for specimens brought back to Copenhagen by Fabricius from Bergen there seem to be no references to such specimens in later publications. Walter O. Cernohorsky who wrote a paper in 1974 on the “Type specimens of Mollusca in the University Zoological Museum in Copenhagen” made no mention of a type for Acesta excavata based on species illustrated in Martini & Chemnitz’ Neues systematisches Con-chylien-Cabinet (1784).

De Besche’s herbarium is in the Bergen Muse-um; however his other collections appear to be lost (Jon Kongsrud, pers. comm.). Thus, if there is a problem with the type specimen it cannot be solved by reference to the de Besche’s collection. The Zoological Museum in Copenhagen retains

only a few specimens of what is left of the Chem-nitz collection; the rest is said to be in the col-lections of the museum in St. Petersburg (if not destroyed during World War II). The conclusion, as far as we have been able to ascertain, is that Fabricius left no material of Ostrea excavata.

Lima – a final solution?

If it is necessary to designate a type specimen, and thus select a neotype, would the solution then be to select a neotype either referring to the drawing of Chemnitz, or probably more cor-rectly, to the two valves labelled by Spengler and kept in the Zoological Museum? In our opinion the specimens kept in the Zoological Museum, which are clearly far older than the drawing of Chemnitz, should be used. But a neotype is not to be designated as an end in itself. Today there is no need to clarify the taxonomical status or the type locality of the species (Järnegren 2006) and the material kept in the Zoological Museum in Copenhagen clearly states the identity of the species described by Fabricius in 1779.

The last years

After returning to Kiel in 1878, Fabricius went back to Copenhagen for a couple of years to publish his most famous work Philosophia In-sectorum in two volumes which described many new insect species (Tuxen 1967). He still had his position in Kiel but only had to give his students a few lectures. The rest of the time he and his family lived in Paris in friendly contact with Cuv-ier, Latreille and other well known naturalists. Although his income could still hardly support his family, he used as much as possible to travel all over Europe, taking the opportunity to write a long series of monographs. His scientific reputa-tion was clearly very well established.

In 1807, while he was in France, Fabricius was told about the British attack on Copenhagen and, being a good Danish patriot, his deep concern for his homeland aggravated his fragile health and made him ill. He travelled as fast as possible back to Copenhagen but he was seriously weakened and during the winter teaching season in Kiel on the 3rd of March 1808 he died aged 63.

Fig. 8. Chemnitz’ drawing from 1784 of Acesta excavata (J. C. Fabricius, 1779).

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Johan Christian Fabricius has to be counted among the most important of Denmark’s natural history scientists. As the most intelligent of all the pupils of Linné he used what he had learned as a solid base for his own research and publications. In this paper our interest has been primarily in his conchology but, as noted earlier, he revolution-ised the entomological systematics of the time, making a new order system for insects, and he made important mineralogical observations in England and Scotland. He travelled widely in Europe to see insect collections and produced many publications describing the new species that he had seen. Apart from his collection in Co-penhagen, the rest are shared between the Natural History Museum, London, the Museum national d’Histoire Naturelle, Paris, the Hope Department of Entomology, Oxford, the Hunterian Museum, Glasgow and the Zoologische Museum in Kiel.

He is considered one of the great entomologists of the 18th Century, probably describing more than 1000 new species. In spite of hardship and economic constraints he used his extraordinary abilities and never failing energies in the service of Science.

ACKNOWLEDGEMENTS

Our sincere thanks go to Mrs Elizabeth Platts for valuable comments on the manuscript and help with the English text. We would also like to thank Lita Greve Jensen from the Bergen Museum for telling us about her ancestor Arent Jansen Greve. We thank Dr Johanna Järnegren for allowing us to use A. Vedelsby’s drawing of Acesta excavata, which she had received as a present after defending her Ph. D. Thesis.

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