P. J. Darlington, Jr.
Australian Carabid Beetles V. Transition of Wet Forest Faunas from New Guinea to Tasmania.
Psyche 68:1-24, 1961.

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PSYCHE
Vol. 68 MARCH, 1961 No. I
AUSTRALIAN CARABID BEETLES V.l TRANSITION OF WET FOREST FAUNAS
FROM NEW GUINEA TO TASMANIA
BY P. J. DARLINGTON, JR.
Museum of Comparative Zoology, Cambridge, Mass. Introduction
Beetles of the family Carabidae (predaceous ground beetles) are numerous in tropical rain forest in New Guinea and numerous also (but less diverse) in cool south temperate rain forest in Tasmania, but no species and hardly any genus is common to the two faunas, and even the dominant tribes are different. However there is no single boundary between the New Guinean and Tasmanian faunas, but a broad and complex transition, which I shall try to describe. My interest in this part of the world began with the Harvard Australian Expedition of 1931-1932, when I collected Carabidae in eastern Australia north to part of the Cape York Peninsula, as well as in southwestern Australia. In 1943-1944 I spent eleven months in New Guinea as an
army entomologist, and was able to collect Carabidae especially in lowland rain forest at Dobodura, Papua, while hospitalized there, and in mountain forest on the Bismarck Range, Northeast New Guinea, in lieu of leave. I have sorted and arranged my own and much borrowed material and am now more than half way through writing "The Carabid Beetles of New Guinea" (see Darling- ton 1952), so that I have a good knowledge of New Guinean Carabi- dae. Recently, from December 1956 to June 1958, I have been again in eastern Australia, traveling and living in a small truck with my wife and fourteen-year-old son, and collecting Carabidae in ~racticall~ every important piece of wet forest from the northern tip of Cape 'Earlier parts of this series are listed in the reference list at the end of this paper.
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2 Psyche [March
York to the southern tip of Tasmania.* A brief itinerary with maps and list of localities has been published (1961). Information and collections obtained during this trip have enabled me to correlate other information and write the present paper. New genera and species i-e- ferred to now (but not by name) will be described in forthcoming numbers of Psyche and Breviora.
The Forests
My "wet forests" are rain forests as classified in "The Australian Environment" (CSIRO 1950, 77-96). That is, they are dense, ever- green (non-deciduous) forests with closed canopies, often (in tropical rain forest) with many woody vines, but with comparatively little low vegetation, the ground being covered with dead leaves and leaf mold rather than grass 01- herbs.
Two main types of rain forest exist in the Australian Region: tropical (including subtropical) (Figs. I, 2) and south temperate (Figs. 3, 4). Tropical rain forest is widely distributed in New Guinea at low and middle altitudes, although in the drier country of southern New Guinea it is replaced by op 11 savannah woodland like that of much of northern Australia. Tropical rain forest occurs also on the eastern edge of Australia in separate tracts spaced irregularly from parts of Cape York south through Queensland and northern New South Wales (map, Fig. 6). The best of this forest in tropical and subtropical Australia as well as in New Guinea is real, Malaysian- type rain forest, although some tracts in Australia are lighter and seasonally drier, and light rain forest sometimes grades into semi- deciduous monsoon forest.
r 7
1 he northernn~ost rain forest in Australia is the tip-of-peninsular (Lockerbie or Son~erset) tract on the tip of Cape York. It is lowland rain forest, but somewhat depauperate (see p. I 7). "This trip was supported in part by a fellowship of the John Simon Guggen- helm Memorial Foundation. I am especially indebted to Dr. L. J. Webb, of the Commonwealth Scientific and Industrial Research Organization, for in- formation on the distribution of rain forest in Queensland, to many members of the Queensland Department of Forestry who aided or guided us in the field, and to Mr. P. J. Killoran, of the Queensland Department of Native Affairs, who arranged our visit to Bamaga and the tip of Cape York. I very much regret that I do not have space to acknowledge other assistance in detail here. EXPLANATION OF PLATE 1
Fig. 1. Tropical rain forest, Lake Barrine, Atherton Tableland, North Queensland (P. J. D. 1932).
Fig. 2. Interior of tip-of-peninsular (tropical) rain forest, from edge of new clearing, Lockerbie, Cape York, Queensland (P. J. D. 1958). This is the habitat of Mecynognathus.




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19611 Darlington -Australian Carabid Beetles 5 Next in order southward is a gap more than 100 miles wide of drier, open savannah woodland (Fig. 5) in which may be an isolated piece of rain forest near the head of the Jardine River, unknown biologically (Brass 1953, pp. 154, I 61 ). Next is the mid-peninsular rain forest system. It extends irregularly and with perhaps slight interruptions from near Iron Range and Mt. Tozer south to the "Rocky Scrub" east of Coen. Altitudinally it ex- tends from near sea level (e.g. at Iron Range) to about 2,000 ft. on the higher summits of the Mcllwraith Range. It includes fairly heavy ram forest, although its quality varies locally. Fig. 5. Rather dry savannah woodland northeast of Coen, Cape York peninsula.
(P. J, D. 1932). Such woodland is an effective barrier to rain forest Carabidae in the tropics.
Next, after another gap more than 150 miles wide of drier, open woodland, is the base-of-peninsular or main tropical rain forest system of North Queensland. Outlying pieces of semi-rain forest of this system arc within sight of Cooktown, and heavier rain forest begins on the coastal mountains (Mt. Amos, Mt. Finnigan) about 20 miles to EXPLANATION OF PLATE 2
Fig. 3.
South temperate rain forest, Lake St. Clair, Tasmania (P. J. D. 1957). On left is transitional wet forest with overstory of big eucalypts; center, heavy rain forest including Nolhafugus, Fig. 4. Interior of old south temperate rain forest, Cradle Valley, northern Tasmania (courtesy Mr. H. J. King, Honorary Photographer, and Mr. Frank Ellis, Director, Queen Victoria Museum, Launceston).



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6 Psyche [March
the south. From here an irregular system of good rain forests extends somewhat discontinuously but with no very wide breaks south to and across the Atherton Tableland and farther south along; a series of plateaus and ranges to the Mt. Spec plateau (Paluma Range) almost within sight of Townsville. Much of this forest system lies between 1,000 and 5,000 ft. altitude, but areas of good rain forest belonging to it occur (or occurred before being cleared) also on the coastal plain east of the Atherton Tableland and in the Mossman-Daintree region. From the southern end of the main tropical rain forest system to below Rockhampton is a gap of nearly 500 miles of dry, open wood- land broken only (so far as I know) by two noteworthy islands of rain forest. One is at about 3,000-4,000 ft. on the crest of the Elliot Range, within sight of (southeast of) Townsville but separated from the northern rain forests by a low, comparatively dry valley. The other, more important island of rain forest is on the Eungella Range about 40 miles inland from Mackay, at about 2,000-4,000 ft. altitude. Scattered fragments of semi-rain forest, for example near Proserpine (Repulse Bay) and Yepoon (Byfield), are relatively unimportant so far as carabid distribution is concerned. South of Rockhampton, in the edge of the south temperate zone, begins what I call the subtropical rain forest system. The first piece of (rather poor) rain forest of this system is on Mt. Jacob east of Many Peaks. Other tracts are widely scattered in southeastern Queensland at low altitudes as well as on mountains (Blackall Range, Bunya Mts., Mt. Tamborine, McPherson Range on the New South Wales border, etc.). The different forest tracts vary in quality, but the best of them approximate tropical rain forest. This system of rain forests extends into northeastern New South Wales at rather low altitudes, although much of it has now been cleared. The more important pieces that still remain are listed and briefly described in my published locality list (1961). The most southern good tract that seemed to me to be tropical-type rain forest is on "Mt. Dorrigo", on the lower (eastern) edge of the Dorrigo Plateau, at about 30ĺ ~o'S., but small pockets of more or less similar forest occur still farther south, even south of Sydney, especially in wet ravines. South temperate rain forest (see again Figs. 3, 4) is different in aspect from tropical rain forest (fewer vines, etc.) and different botanically, often dominated by southern beeches (Nothofagus). Such forest is widespread in southwestern Tasmania and occurs in isolated tracts elsewhere in Tasmania (see paper referred to above for details). Isolated tracts of similar forest occur on plateaus and moun- tains in southern Victoria including the Otway Ranges southwest of



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19611 Darlington - Australian Carabid Beetles 7 Melbourne and some of the southern "Victorian Alps" east of Mel- bourne. This kind of forest occurs also, at wide intervals, on isolated plateaus in eastern New South Wales, notably on the plateau of the Mt. Royal Range (Barrington Tops and Tomalla Tops) at about 31' 50' S. and on the higher part of the Dorrigo-Ebor Plateau (especially at Point Lookout in New England National Park) at about 30ĺ S. Both these plateaus reach about 5000 ft. above sea level. The northernmost Nothofagus in Australia is still farther north, on the southern border of Queensland, where small tracts of old trees exist on the highest points of the McPherson Range, at about 28O 20' S. and 4,000 ft. altitude. Nothofagus does not occur on the mountains of tropical North Queensland but is dominant in New Guinea in mountain forests between about 6,500 and 10,000 ft. (Womersley and McAdam 1957, p. 25). However, south temperate groups of Carabidae do not occur in the New Guinean Nothofagus forests. The distribution of tropical (including subtropical) and south temperate rain forest is shown, rather diagramatically, on the accom- panying map (Fig. 6). The map is based partly on the vegetation map in "The Australian Environment" (CSIRO 1950, pp. 88-89) and on Brass's (1953, p. 152) map of Cape York rain forests, but many details are modified according to my own observations. In most
cases rain forest is not continuous within the boundaries shown, but occurs as irregular, sometimes discontinuous tracts and strips inter- spersed with savannah woodland (in the north) and/or sclerophyll forest (in the south). The two kinds of rain forest overlap widely in New South Wales. Within the area of overlap south temperate rain forest is usually above (at higher altitude than) tropical rain forest, but there is some mixing.
The Carabidae
The wet-forest Carabidae of New Guinea and Australia, including Tasmania, are numerous, diverse, and complex in ecology and distri- bution. They form three general ecological groups. Those that live on the ground without being specially associated with surface water are mesophiles or geophiles. Those that live on the ground beside streams or ponds or in swamps are hydrophiles. And those that live on tree trunks or in foliage above the ground are arboreal. According to my (1943, p. 41) rough analysis of the Australian casabid fauna, at least half the species are geophiles, not quite a quarter hydrophiles, and not quite a quarter arboreal. The carabid fauna of New Guinea divides in something like the same way, although I cannot yet give exact figures.




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NEW GUINEA
/ ( rain forest
Mid-pen.
rain forest
Cooktown
Base-of -pen,
or main tropical
rain forest
^/ĺ´Eungell Range
Rockhampton
Tropic of C.
Subtropical
rain forest
Brisbane system
Mt. Royal Rge. ::a
/




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19611
Darlington - Australian Carabid Beetles
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State of wings of Carabidae is correlated with ecology and distri- bution. Most Carabidae in most parts of the world have fully devel- oped inner wings and can fly, but some have lost their wings (except for vestiges) and become flightless. The Australian carabid fauna includes an unusually large proportion of flightless species : according to my rough analysis (loc. cit.), nearly 45% of all Australian Carabi- dae have atrophied wings, and many genera and even some tribes are wholly flightless. Most hydrophiles and arboreal forms have retained their wings and can fly, but about 75% of Australian geophile Carabi- dae are flightless, and flightless groups are common everywhere in Australia, at low and high altitudes and in wet and dry climates, and some are well represented in the tropical as well as the temperate parts of the continent. In New Guinea flightnessess is rare among lowland Carabidae. This accords with the general rule that most Carabidae in most wholly tropical lowland areas are winged. On mountains in New Guinea, however, as on many tropical mountains elsewhere, flightless geophile Carabidae are numerous. New Guinea-Tropical Australian Relationships Probably the first fact that strikes entomologists collecting in the rain forests of tropical Australia is that some of the insects are species that occur in New Guinea.
This is expected. The Australian rain
forests themselves are re dominantly New Guinean (or Malaysian) both in aspect and in botanical relationships (CSIRO 1950, pp. 95- 96; Brass 1953, p. 154) ; many mammals in the North Queensland rain forests belong to New Guinean genera or even species; and so do many birds. Some Carabidae are common to New Guinean and Australian rain forests. For example Syleter papua Darl. extends to the tip of Cape York, living on the ground in shaded swamps. Morion longipenne Putz. of New Guinea extends to the main North Queens- land rain forests, on and in fallen logs. And Violaqonum violaceum (Chd.) is common in rain forest in New Guinea and eastern Australia south at least to near Rockhampton, in accumulations of dead leaves on the ground and in thick foliage. Besides shared species like these (there are many others among Carabidae) the New Guinean and Australian rain forests share some geographically restricted genera, for example Platycoelus (Chlaenioiclius), Loxandrus, and Stricklandia, EXPLANATION OF PLATE 3
Fig. 6.
Distribution of rain forests in eastern Australia. Solid lines enclose principal areas of tropical (including subtropical) rain forest; broken lines, of south temperate rain forest. In most cases rain forest is not continuous within the boundaries shown but occurs in discontinuous or scattered tracts. See text for further details.




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10 Psyche [March
as well as many more-widely distributed genera. Up to a point, there- fore, the Carabidae agree with the forest trees, mammals, and birds in showing a considerable number of species and genera common to the rain forests of New Guinea and tropical Australia. When I was collecting on the Atherton Tableland in northeastern Australia in 1932, I found not only many Carabidae of obviously New Guinean groups but also, in rain forest, many species of Australian groups not known to occur in New Guinea. Included were striking endemic species of Notononius, Trichosternus, Leiradira, Pamborus, and Mystropomus. Knowing, as I did, that the rain forests of Australia and New Guinea had much in common, and knowing that the Carabidae of New Guinea were poorly collected, I imagined in New Guinea a rich fauna of the genera just named, perhaps in rain forest at middle altitudes, but wholly unknown. It was a sort of El Dorado for the future, to a young and enthusiastic carabid student. But now that I have collected in New Guinea and seen thousands of Carabidae collected there by other persons, I know that this El Dorado does not exist, and I know why. All the Carabidae common to the New Guinean and Australian rain forests are winged and probably fly. All the genera mentioned above as represented in rain forest on the Atherton Tableland are wholly flightless, and I know now that there is no direct relationship between any flightless Carabidae of the New Guinean and Australian rain forest^.^ The difference between the flightless Carabidae of Australia and New Guinea goes far beyond mere differences of species and genera. The composition and origins of the two faunas are fundamentally different. Flightless Carabidae are numerous everywhere in Australia, even at low altitudes in the tropical part of the continent including Cape York. Many of the species belong to wholly flightless genera or even flightless tribes that have evidently been in Australia a long time. Derivatives of old Australian flightless groups dominate the flightless ground-living carabid fauna of tropical rain forest in Australia. In New Guinea, in contrast, no primarily flightless groups of Carabidae occur at low altitudes. A very few species of the primarily winged 'If tiger beetles are considered Carabidae, Tricondyla aptera 01. is an exception to this rule. The genus Tricondyla is primarily Oriental and is wholly flightless. Nevertheless T. aptera has reached New Guinea, probably rather recently (it is only slightly differentiated there), and has got beyond New Guinea to the mid-peninsular rain forests of Cape York. (It has reached the Solomon Islands and New Hebrides too.) It is a good sized (nearly an
inch long), big-eyed, ant-like, active insect, which lives on tree trunks in rain forest. It has probably dispersed on floating trees, which ground-living Carabidae are not likely to do.




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19611 Darlington - Australian Carabid Beetles 11 genera Clivina, Tachys, Lesticus, Platycoelus, and Loxandrus have undergone wing atrophy at low altitudes in New Guinea (Darlington in press), but they have evidently done it recently, in situ. Some of the species are still dimorphic, with fully winged individuals occurring with the short winged ones, and all the short winged lowland species are closely related to long winged ones that still exist in New Guinea. It is only above about 5000 ft. in the mountains that flightless Carabi- dae become numerous in New Guinea, and they too have apparently undergone wing atrophy in situ. That is, they have been derived on the mountains of New Guinea from winged ancestors, and do not represent flightless stocks of other regions. This is my conclusion after making formal studies of the New Guinean representatives of the two principal tribes concerned, the Agonini (Darlington 1952, especially table p. 108) and Pterostichini (in press). Besides the change of specific flightless stocks from New Guinea to Australia there is a change of dominance of tribes. In New Guinea, Agonini are much more numerous than Pterostichini, and most flight- less Carabidae of the island are agonines. But in Australia, even in
the tropical rain forest, Pterostichini are overwhelmingly dominant and include most of the flightless forms. This striking shift of domi- nance is further discussed on page 22.
The first important finding of the present study, then, is that, al- though the rain forests of New Guinea and tropical Australia are similar and share many species of plants, mammals, birds, and winged insects including many winged Carabidae, they have wholly different faunas of flightless Carabidae, which differ not only in taxonomic details but also in general ecology (in relation to altitude), in origin of the flightless stocks, and in relative dominance of tribes. Transition in Australia: South from the Tropics Now to be considered is the transition of wet forest carabid faunas within the limits of Australia and Tasmania. Five important genera of flightless geophile Carabidae are mentioned above as occurring in rain forest on the Atherton Tableland. Of these five genera, Notonoznus is most dominant. It is a genus of about 100 species, confined to eastern and southeastern Australia and Tas- mania except for one species isolated in southwestern Australia. The genus' northern limit is between Daintree and Cooktown. It is repre- sented by several species (some very localized) in the main tropical rain forest system of North Queensland, where it seems to be confined to rain forest. It is well represented in the subtropical rain forests of South Queensland and northern New South Wales and south through



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12 Psyche [March
eastern New South Wales and southern Victoria; in these areas some species occur not only in rain forest (including south temperate rain forest) but also in wet sclerophyll forest and good savannah woodland. However only two groups of the genus reach Tasmania and only one group (two related, primarily allopatric species) occurs in rain forest there.
Trichosternu~ is a genus of 25 or more species confined to eastern Australia, except that one species is isolated in southwestern Australia (Darlington 1953, p. 94). The genus' northern limit is between Daintree and Cooktown. It occurs (several species, some very local- ized) throughout the main rain forest system of North Queensland, where it is apparently confined to rain forest. It is well represented also in the subtropical rain forest system of South Queensland and northern New South Wales, and in this area some species occur in savannah woodland as well as in tropical-type rain forest, and some have entered south temperate rain forest on the Dorrigo-Ebor plateau and the Mt. Royal Range. The southern limit of the genus is some- where in east-central New South Wales, probably not far north of Sydney.
The northern limit of Leiradira (or of the group of genera that includes Leiradira) is between Daintree and Cooktown. This genus too occurs in much of the main tropical rain forest system of North Queensland, being represented there by several distinct species each more or less localized, but the genus may be absent in the southern extension of the main tropical rain forest system south of the Atherton Tableland. It is represented also by several species in the subtropical rain forests of South Queensland etc. Its southern limit is apparently on the lower, eastern edge of the Dorrigo plateau. It is confined to eastern Australia. It is wholly or chiefly a rain forest genus in all parts of its range.
The three preceding genera are all Pterostichini. All their species are flightless geophiles.
Additional flightless geophile pterostichines are localized in all the different rain forest areas of Australia from Cape York to Tasmania. Examples are Mecynognathus in the tip-of- peninsular forests ; Paranurus in the mid-peninsular forests ; Loxo- genius and undescribed genera in the main tropical rain forest system; Nursus s. s., Liopasa, Ceratofer~nia, Zeodera, and Notolestes in the subtropical rain forest system; Loxodactylus in the wet forests of southern Victoria; and Rhabdotus in those of Tasmania. (It should be added that Australia possesses many winged pterostichines as well as these and other flightless genera.)




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19611
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Of non-pterostichines, Pamborus is noteworthy. It is confined to eastern Australia and is one of the two known genera of the tribe Pamborini. (The other is monotypic Maoripamborus in New Zea- land - Brookes I 944.) The northern limit of Pamborus is probably near Cooktown. Four species of the genus occur in the main tropical rain forest system of North Queensland, chiefly or wholly in rain forest. Six other species occur in South Queensland and New South Wales. Some of them occur mainly in (sub)tropical rain forest, but viridis inhabits savannah woodland and some other species occur in open woods as well as rain forest, and some enter south temperate rain forest on the high plateaus of north-central New South Wales. The southern limit of the genus is near the Shoalhaven River about 70 miles south of Sydney. (Old records for Victoria are probably errors.) The genus Mystropomus is the only Australian representative of the pantropical tribe Ozaenini. The genus is confined to eastern Australia. Its northern limit is between Daintree and Cooktown. A single species (two subspecies) occurs throughout the main tropical rain forest sys- tem of North Queensland, and is apparently confined to rain forest. Another, variable species (two subspecies) occurs in the subtropical rain forest system, and extends into more open woodland. The south- ern limit of the genus is apparently near Sydney. These five genera dominate the flightless geophile carabid faunas of the main tropical and subtropical rain forest systems of eastern Australia. Their distribution is notable in several ways. All five genera reach an approximately common northern limit, north of Dain- tree and south of or near Cooktown. All five genera are widely dis- tributed both in the main tropical and in the subtropical rain forest systems. These two forest systems are separated by a wide barrier of comparatively dry, open forest in which is one important "island" of rain forest, on the Eungella Range west of Mackay, and all five of