AUSTRAL I AN NATURAL HISTORY Published Quarterly by the A ustra/ian !vluseum, College Street, S; dney Editor : F. H. TALIJOT, P h. D ., F.L.S. Annual Subscription , $1.40 po5ted VOL. 16, 0. 2 JU E 15, 1968 r CONTENTS PAGE A usTRALIA!\ DRAGO:-IFLIES-J. A. L. Warson 33 T HE SEA-LIONS OF D A GEROUS R EEF- B. J. Mm·!oll' 39 FISHES B ENEATH ANTARCTIC ICE- Dona/d £. Woh/sch/ag 45 D ISTR IBUTIO A D ADAPTIVE DIVERSITY OF TRA PDOOR SPIDCRS- Barbara York Main 49 THE LITTLE B E 'T -\ I GED B AT- E VOLUTIO I. PROGRLSS- P. D. Dll'yer 55 ECOLOGICAL A SPECTS OF SERPULID fou u , G-Da/e Straughan 59 BOOK R EV IEWS .. 48, 54, 58, 64 e FRO T COVER : A large burrowing frog, Cyclorana australis, from central Queens land. This specie grows to nearly 5 inchc in length, and is found in many pans of Queensland. the Northern Territo ry, and Western Australia. During the dry cason it burrows up to everal feet underground, where it aestivates in a pecial cavity until, with the coming o f rain, it comes to the surface to feed and breed. (Pho to: Howard Hughes). BACK COVER: A de ert gecko, Lucasiu111 daiiiOf!lilll, from a mallee-spinifex community in central-weslCrn New South W ales. This gecko. which grows to about 4 inches in length. is found commo nly in the a rid spinifex or porcupine grass (Triodia pecies) area in all mainland States. Like most geckos it is in­ sectivorous, but is especially partial to termites. The female no rmally lays two parchment- helled eggs. (Photo: C. V. Turner). Front view o f the dragonfly Rhyorhemis graphiprera (Rambur) in a typical perching position. The wing­ span is approximately 6 cm (about 21 inches). The abdomen is lnidden behind the thorax. AUSTRALIAN DRAGONFLIES By J. A. L. WA T 0 Curator of Odonata, Dh•ision of Entomology, CSJRO, Canberra, A.C.T. ET G very con.spicuou insects, dragon­ larger dragonflie , as food and bait for fi sh ; flie are fa milia r to most of us. Their what Au tralian trout fisherman has not Bla rge ize, powerful flight, rapacious habits heard of mud-eye ? a nd bright colo urs all command attention. In po int of fact, the Odonata, the o rder of They have common na mes in many insect to wh ich the dragonflies belong, language ; the Japane e have long accorded con titute le s than 0·5 per cent of the known them a prominent place in art; they were species of insects. The o rder contains two o bvious models fo r the early designers of main subo rder , the Anisoptera or dragonflies :flying machines; and the sustained interest proper, la rge, sturdy insects which generally of collecto rs ha provided us with a better rest with the wings spread, a nd the Z ygoplera k nowledge of the world fauna than exists for or dam elflies, lim insects generally resting most other in ect . The attention of laymen with the wi ngs closed above the body. has al o been attracted by the larvae of the owaday the name dragonfly is loosely June, 1968 Page 33 applied to both subo rders, a ltho ugh its older a l o bulky, rugged creatures, and, unlike usage, dating back some four centuries, other dragonflies, live in burrows in wet applied only to the larger species now mud. Their diet is correspondingly different recognized as Anisoptera. and includes earthworms, terrestrial beetles, and other small a nimals of the bogs. All dragonflies are active predato rs. T he adults are highly speciali zed for catching a nd Another primitive group is the subfamily consuming other insects in fli ght, and flies, eopetali inae, two species of which occur in wasps, moths. and even sma ller dragonllies southeastern Australia, the remainder livi ng commonly fall victim to them. The larvae, in South America. The family Ae hnidae, to which are almost always aquatic, use their which the neopetaliines belong, a lso incl udes uniq uely modified labium to catch food. many common and widespread dragonflies, When suitable prey comes within range, the mostly la rge. The two Australian neo­ la bium is shot forward. and the unfortuna te petaliines are Austropetalia patrrcw anima l is trapped between the apposed teeth (Tillyard) from the Blue Mo unta ins (New a nd spines of the two latera l lobes. Neither South Wales) and Victo ri a, and Archipewlia larva nor adult is harmfu l to man, despite auriculata T illyard from the mo untains of the na me ho rse-stinger which is commonly Tasma nia, the most primitive living aeshnid applied to the adult: rather the reverse, fo r known. Both species, in common with the diet of both larvae and adults often other member of the subfamily, have a row includes flies a nd mosquitoes. of reddish spots along the leading edge of each wing. T wo unrelated Australian damselflies. M ore than 4,000 species in world Hemiphlebia mirabilis Selys and Chorismagrion The Australian dragonflies are few in risi Morton, are unique in showi ng venationa l number, the total number of species being characteristics otherwise known only in probably less than 300, compared wi th the fossils from the Permian period. [t is world fauna of something over 4,000 species. possible that the venational characteristics On the other hand, the Australian fauna a re secondary, in which case the arguments includes a great number of ancient or for affinity with the fossils would founder; problematical forms. There are dragonfl ies yet such characteristics would be striking closely a llied to the species of Jurassic times, cases of parallel evolution, especially in I 50 m illion years ago, in the age of reptiles; Hemiphlebia. Both species have a genu s species whose only known relatives live in to themselves, and occur only over a limited Chile: species whose nearest counterparts are range; Hemiph/ebia mirablis apparently fossils from the Permian period, approxi­ occupies only a short tretch of the Goulburn mately 250 million years ago; a nd, at the R iver in Victoria, a nd Chorismagrion risi other extreme, there is Pantala flavescens is confined to the rai nforests of northern (Fabricius), a species known from temperate Queensland. and tropical zones all around the world. The known larvae of the m o re pnm1t1ve P redominant among the ancient groups is Odonata breed in permanent water, generall y the family Peta luridae, a family abundant in streams. They commonly take more than among the dragonflies of the Jurassic, and a year, sometimes up to 6 or 7 years, to reach now reduced to nine li ving species. Four the adult stage, so it seems that the larvae of these live in Australi a, o ne in New Zealand, of ancient dragonfli es first colonized o ne in Chile, two in North America, and one permanent waters, where temperature and in Japan. The fo ur Australian species all oxygen content were fairly even. But how belong to the genus Petalura, which is can we be sure that dragonfly larvae were co nfined to Australia; two occur in no rth originally terrestrial? The petalurids give Q ueensland, one ranges from south Quee ns­ us a clue, but the respiratory systems of land to central New South Wa les, and the larval dragonnies provide more convincing fourth is confined to southwestern Australia. evidence. Terrestrial insect breathe air All are huge dragonflies, and Peta!ura through segmentally arranged apertures, the ingentissima Tillyard from north Queensland. spiracles: aquatic insects generally breathe with a wing-span of up to I E.5 cm, is the by means of gi ll s of various types. D ragonfly largest living dragonfly. T he larvae are la rvae have gills, at least four distinct and Page 34 Australian N atural History The damselfly Agriocnemis dobsoni Fraser, pho tographed in a swamp near lnnisfail, Queensland. The tiny Agriocnemis, all only 2 to 3 cm long, have a di tribution similar to that of Pseudagrion. independent types being represented, some a nd o utheastern Au tralia respectively; o n the out ide of the abdom en a nd others in Argiolestes pusillus Tillyard occurs only in the rectum. Tn addition, however, relics of southwestern Australia; and Austrocordulia a bdo minal spiracles are commo n to all. We refi·acta Tillyard is confined to eastern can be sure that they were o nce terrestrial, Australia, in the coastal regio n from southern presumably in the moi t atmospheres of the New South W a les to northern Queen land. mid-Palaeozoic era. One of the striking features of "modern·· ''Opportunists'' dragonflie , together with a few of the older Secondly, we find pecies that have forms, is that they have forsaken the hortened their larval life to a peri od permanent stream and can now breed in compatible with the duration of temporary ephemeral and often ha llow and warm ponds. Such species are opportunists, layi ng waters. The species that have overcome the eggs when water is available, and fl ying far problem of breeding in temporary waters to find it. Thus the adults a re widespread have d o ne so in one o f two ways. Firstly, throughout Australia. and are better known the larvae of several unrelated dragonflies, than those of other specie . Perhap the mo tly species that breed in boggy place . mo t interesting point i that, like the pecic have developed the capacity to withstand that have developed re i tance lo drying.