The first published record of any New Zealand Collembola appeared in 1894; and from then on, until 1925, little work was done upon New Zealand forms of this interesting group of insects. During the past nine or ten years, however, several papers have appeared in various journals dealing with the Collembolan Fauna of New Zealand, but these, without exception, have treated of small collections from relatively restricted localities. The present paper is the first attempt to deal with the Collembolan Fauna of this country as a whole, incorporating material collected systematically over wide areas of the land and reviewing all species previously described from New Zealand. During the past nine years I have collected these insects from as many of the Dominion's rapidly-diminishing areas of native forest and grassland as it has been possible to visit, with the object of discovering as nearly as possible the extent of the indigenous Collembolan Fauna. As a result this paper adds 101 new species and 15 new sub-species to our Collembolan Fauna and brings the total number of recorded Collembola from New Zealand up to two hundred and eleven, including the sub-species.
I do not suggest that this result is final, as there are many localities which, so far, I have been unable to visit, and which have not yet been explored for Collembola. Notably in this connection I would mention Stewart Island and the “heel” of the South Island from Milford Sound to Dusky Sound and east to Tuatapere. These regions and the higher alpine regions above 4000 ft. will, I am sure, be found to contain many more interesting species of these insects.
In this work I have from time to time received collections of material from workers in allied fields. Such collections are suitably acknowledged in the appropriate positions in the text; and I take this opportunity of expressing my thanks to these persons for their help. I have also to express my thanks to Dr. R. A. Falla, Director of the Canterbury Museum, Christchurch, New Zealand, for the loan of the late Dr. G. H. Carpenter's New Zealand material deposited there, and also to Mr. H. Womersley, of the South Australian Museum, Adelaide, for the loan of New Zealand material described and recorded by him. I desire, also, to express my thanks to the Director of the Dominion Museum, Dr. W. R. B. Oliver, for his assistance and advice during the preparation of the manuscript, and for helpful suggestions made from time to time.
Several thousands of specimens have been examined in the course of this study, and from these an extensive reference collection of permanent mounts on microscope slides has been prepared and deposited in the Dominion Museum at Wellington.
As much of the specialist literature dealing with the Collembola is scattered through a multitude of scientific journals and other publications, some of which are difficult to trace, and, in this country, often difficult to obtain, and in order to make this paper of the utmost possible use to other workers in this field in New Zealand, I have included a key for the separation of all the known families, sub-families and tribes of the Collembola. In addition, with all genera, where more than one species is known from this country, I have prepared keys to assist in their separation. In all cases of species previously recorded or of new record of exotic species a full description is given so that the present work at the time of publication may be as complete a record as possible of the Collembolan Fauna of New Zealand. I have recorded synonyms in specific names only in so far as it concerns publications referring to New Zealand.
Collembola are small to minute insects often as short as 0·25 mm. and seldom reaching as much as 10 mm. in length. They are found in almost all damp situations such as in leaf mould under trees, or in the forest; under the bark of trees; in damp soil, moss or humus; under stones; among plant roots; on water; in the intertidal zone of the sea-shore, in crevices in the rocks, and sometimes on the damp sand. They are the only insects known in which the abdominal segments are reduced to six in number, and in which primitive abdominal appendages have been preserved and evolved into special organs other than tail cerci. Before proceeding to a detailed study of the forms enumerated in this paper it is necessary to be clear as to the meaning of the following terms. The Body means the body in its general sense, that is, including the head, thorax, and abdomen, but not necessarily the appendages. Measurements of length are given from the anterior tip of the head to the posterior tip of the abdomen. The flexed setae are long setae which usually occur on the dorsal surface and in which the apex is flattened and more or less bent over and ciliated. The ciliations may extend down the shaft of the seta.
Ciliated setae are setae covered with short, fine hairs.
Serrated setae are, as their name implies, setae with distinct teeth or serrations.
Plumose setae are setae in which the ciliations are long and thick, giving the appearance of a fine flue-brush or plume.
Bothriotrichia are long, fine, ciliated, wavy hairs, sensory in function.
Ant. II, Th. III, or Abd. IV are abbreviations used to denote the different segments of the antennae, thorax and abdomen.
The empodial appendage is the secondary claw sometimes referred to by other writers as the accessory claw, unguiculus, etc.
|1.||Body elongate, segmentation distinct, abdominal segments generally all separated, fusion, if present, being evident only on posterior segments of abdomen. Sub-order Arthropleona Börner||2|
|Body globular, thoracic and first four abdominal segments completely fused, Abd. V and Abd. VI generally distinctly demarcated from anterior portion of body.|
|Sub-order Symphypleona Börner||18|
|2.||All segments essentially similar. Prothorax distinct and never hidden below mesotergum, and dorsally with setae. Scales absent. Antennae short and four segmented. Cuticle generally granulate or tuberculate. Anal spines and pseudocelli often present. Post-antennal organ generally present.|
|Super-family Poduroidea Womersley||3|
|Body segments usually dissimilar. Prothorax without setae dorsally and usually reduced and hidden under mesotergum. Antennae long and from four to six segmented. Cuticle smooth. Scales present or absent. Postantennal organ present in Isotominae absent in other sub-families.|
|Super-family Entomobryoidea Womersley||8|
|3.||Body without pseudocelli. Ocelli present or absent. Postantennal organ usually present and well developed. Sensory organ of Ant. III with sense rods but without sense clubs or outer papillae. Ant. IV always with retractile sensory knob.||4|
|Body with pseudocelli. Ocelli absent. Postantennal organ present and well developed. Sensory organ of Ant. III with sense rods, sense clubs, and, generally, papillae and protective setae. Ant. IV seldom with sensory knob, but often with sub-apical pit. Anal spines usually present.|
|Family Onychiuridae Lubbock||7|
|4.||Head hypognathus. Ocelli on hind part of head. Dentes bowed horizontally, annulated distally, and reaching forward beyond ventral tube.|
|Family Poduridae Börner (not found in N.Z.).|
|Head obliquely prognathus. Ocelli present or absent. If present, then situated on front part of head. Dentes not annulated, straight, and seldom reaching forward to ventral tube.|
|Family Achorutidae nov.||5|
|5.||Mouth parts for chewing, the mandibles with well-developed molar plate. Ocelli and postantennal organ present or absent. Furcula generally present, but sometimes reduced, never reaching forward to ventral tube. Empodial appendage present or absent. Pseudo-celli absent.|
|Sub-family Achorutinae Börner.|
|Mouth parts for sucking, usually projecting forward beneath head, cone-like in shape. Mandibles, if present, without any molar area. Empodial appendage generally absent. Postantennal organ and furcula present or absent.|
|Sub-family Neanurinae Börner||6|
|6.||Sixth abdominal segment small and rounded, never bilobed. Body generally without any large segmental tubercles.|
|Tribe Pseudachorutini Börner.|
|Sixth abdominal segment large and bilobed. Body with large segmental tubercles.|
|Tribe Neanurini Börner.|
|7.||Sensory organ of Ant. III with the two sense clubs curved towards each other, often with an accessory lateral club. Body long and narrow. Postantennal organ with numerous tubercles. Empodiai appendage present and with or without terminal bristle. Furcula absent.|
|Sub-family Tullberginae Bagnall.|
|Sensory organ of Ant. III with the two sense clubs not curved towards each other. Postantennal organ with few or many tubercles. Body broad and relatively more robust. Empodial appendage well developed. Furcula generally absent, but if present, then rudimentary.|
|Sub-family Onychiurinae Bagnall.|
|8.||Hind coxae with a small specialized area of fine hairs (trochanteral organ). Inner edge of claw generally with basal groove. Abd. IV generally longer than Abd. III. Furcula present. Scales and setae often ciliated. Family Entomobryidae Schaeffer||15|
|Hind coxae without trochanteral organ and inner edge of claw without basal groove.||9|
|9.||Abd. III and Abd. IV approximately equal in length; Abd. IV sometimes a little longer. Scales present or absent; if present, then entirely without longitudinal striae. Bothriotrichia present or absent. Family Isotomidae Schaeffer||10|
|Abd. III much longer than Abd. IV. Scales present or absent, but if present, then with longitudinal striae. Postantennal organ absent. Furcula present. Family Tomoceridae Schaeffer||13|
|10.||Head more or less hypognathus. Antennae arising from middle of head. Furcal segment with two stout ridges.|
|Sub-family Actaletinae Börner.
(Not found in New Zealand.)
|Head prognathus. Antennae arising from front half of head. Furcal segment without ridges. Furcula and postantennal organ generally present.||11|
|11.||Scales present. Postantennal organ present, circular and rosette-like. Mucro long with numerous teeth, but without any setae.|
|Sub-family Oncopodurinae Börner.
(Not found in New Zealand.)
|Scales absent. Postantennal organ generally present, and when present, simple. Anal spines sometimes present.|
|Sub-family Isotominae Schaeffer||12|
|12.||Anus not terminal, being obliquely behind or ventral. Anal spines and empodial appendage present or absent. Furcula sometimes absent.|
|Tribe Anurophorini Börner.|
|Anus terminal. Anal spines present or absent. Empodial appendage and furcula present and well developed.|
|Tribe Isotomini Börner.|
|13.||Dentes at least indistinctly annulated and corrugated, but not segmented. Mucro small and without setae. Ant. III not very much longer than Ant. IV.|
|Sub-family Lepidophorellinae Börner||14|
|Dentes not or only slightly annulated and corrugated, but segmented and spined. Mucro long with setae. Ant. III as a rule much longer than Ant. IV.|
|Sub-family Tomocerinae Börner||15|
|14.||Scales present and distinctly ribbed, though sometimes tending to hyaline. Mucro falciform. Dentes spined and generally with spine-like scales. Empodial appendage simple. Antennae four-segmented.|
|Tribe Lepidophorellini Womersley.|
|Scales absent. Mucro toothed. Ant. III and IV and distal part of Ant. II annulated. Dentes without spines.|
|Tribe Neophorellini Womersley.
(Not found in New Zealand.)
|15.||Ocelli present, six on each side. Ant. III much longer than Ant. IV.|
|Tribe Tomocerini nov.|
|Ocelli present, eight to each side. Ant. III shorter than Ant. IV. Dentes slightly annulated and corrugated.|
|Tribe Neocerini nov.|
|16.||Dentes long and slender, prominently annulated and corrugated. Mucro small. With or without scales or ocelli.|
|Sub-family Entomobryinae Börner||17|
|Dentes not annulated or corrugated., long, but not or only slightly tapering.||18|
|17.||Antennae with four segments.|
|Tribe Entomobryini Börner.|
|Antennae with five or six segments, sometimes with segments I and II subdivided. Mucro bidentate with basal spine.|
|Tribe Orchesellini Börner.|
|18.||Dentes without ciliated or fringed scales and setae dorsally. Dentes with or without spines. Empodial appendage with four-winged edge. Mucro plump and generally indistinctly separated from dens. Body with or without scales. Ocelli present.|
|Sub-family Paronellinae Börner.|
|Dentes dorsally with ciliated or fringed scales and setae or spines. Empodial appendage with three-winged edge or reduced. Scales present. Ocelli absent.|
|Sub-family Cyphoderinae Börner.
(Not so far discovered in New Zealand, but they should occur.)
|19.||Antennae arising from, or in front of, middle of head, four-segemnted, and always very much shorter than head. Head without elevated vertex. Coxae of legs elongated and on outer side longer than trochanter. Ocelli and postantennal organ absent. Body with or without papillae. Tenaculum without bristles. Furcula present. Bothriotrichia absent. Very small species seldom more than 0.25 mm. long.|
|Family Neelidae Folsom.|
|Antennae inserted behind middle of head, four-segmented, sometimes with subdivided segments, and generally much longer than head. Head with distinctly elevated vertex over neck. Coxae not elongated; on outer side much shorter than trochanter. Tenaculum usually with bristles. Bothriotrichia present.|
|Family Sminthuridae Lubbock||20|
|20.||Vesicles of ventral tube with smooth walls. Cuticle of body granular. Tenaculum with lateral appendages at base of rami. Traces of thoracic segmentation present.|
|Sub-family Sminthuridinae Börner||21|
|Vesicles of ventral tube with tuberculate or “warted” walls. Traces of thoracic segmentation absent.||22|
|21.||Anal and genital segments fused with two sensory setae on each side.|
|Tribe Sminthuridini Börner.|
|Anal and genital segments separated, sometimes the latter fused with the furcal segment. Genital segment with one sensory seta only to each side.|
|Tribe Katiannini Börner.|
|22.||Antennae bent between segments III and IV. Ant. IV longer than Ant. III and never subdivided. Tenaculum without lateral appendages. Furcal segment without dorsal papilla.|
|Sub-family Sminthurinae Börner||23|
|Antennae bent between segments II and III. Ant. IV shorter than Ant. III and both segments III and IV or only III sometimes sub-divided. Furcal segment with large dorsal papilla and three pairs of sensory setae. Tenaculum with basal appendages.|
|Sub-family Dicyrtominae Börner.|
|23.||Clavate tenent hairs present, 2–3 appressed. Empodial appendage present or absent.|
|Tribe Bourlettiellini Börner.|
|Clavate tenent hairs generally absent; if present, then separated and outstanding. Claw sometimes with tunica or sheath. Empodial appendage always present.|
|Tribe Sminthurini Börner.|