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Volume 79, 1951
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New Zealand Drosophilidae (Diptera)
I—Introduction and Descriptions of Domestic Species of the Genus
Drosophila Fallén

[Read before the Auckland Institute, November 15, 1950; received by the Editor, December 1, 1950]

Summary

Descriptions and records of occurrence in New Zealand are given for the following species of the family Drosophilidae: Drosophila busckii Coq., D. repleta Woll., D. hydei Sturt., D. simulans Sturt., D. melanogaster Meig., D. brouni Hutt., D. funebris (Fab.). It is considered that D. clarkii Hutt. = funebris (Fab.), and D. immigrans Sturt. = brouni Hutt.

Introduction

Knowledge of the family Drosophilidae in New Zealand is very fragmentary. Only six species in two genera have been recorded. Among these, four were described as new species, viz.: Drosophila brouni, D. marmoria and D. clarkii by Hutton (1901) and Leucophenga atkinsonii by Miller (1921). The two other species recorded are D. ampelophila Loew (= melanogaster Meigen) by Broun (1904) and D. rubrostriata Becker (= busckii Coquillet) by Cottier (1933).

A large collection of Drosophilidae has accumulated at the Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, and it is from this material, supplemented by collections in other New Zealand Institutions that the present study is being made.

Grateful acknowledgment for permission to examine Hutton's type material is made to the Director, Canterbury Museum, and for permission to examine Drosophilid collections to the Directors, Canterbury Museum, Cawthron Institute, Entomology Research Station, and Dominion Museum.

Systematic Position and Characters of the Family

The following shows the position of the family in the classification scheme.

  • Order Diptera

  • Suborder Brachycera

  • Division Cyclorrhapha

  • Superfamily Muscoidea

  • Section Acalyptratae

  • Family Drosophilidae

The chief characters which distinguish the Drosophilidae are as follows: Small acalyptrate flies. Arista plumose, pectinate or rarely pubescent. Third antennal segment rounded or oval. Front with conspicuous bristles. Face with distinct antennal grooves separated by a distinct carina. Vibrissae present. Post-verticals convergent.

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Costa usually twice broken. Sub-costa vestigial. First longitudinal vein short. Discal and second basal cell usually united. Anal cell present.

Characters of the Genus

Fallén (1823) erected the genus Drosophila and recorded it as having the following characteristics:

“Arista plumose; vibrissae and ocellars present; three orbitals, lowermost proclinate, upper two reclinate, middle one smaller than the others; post verticals large; one or more humerals; one presutural; two notopleurals; two supraalars; two postalars; one to three sternopleurals; mesopleurae bare; two dorsocentrals; prescutellars usually absent; two pairs of scutellars, posterior ones crossed; disk of scutellum bare; acrostichal hairs in six or more rows in front of transverse suture, four or more between the anterior dorsocentrals; preapicals evident at least on third tibia; costa twice broken, reaches apex of fourth vein; two small bristles just before distal costal break; discal and second basal cells confluent; anal cell present, often incomplete.”

The external anatomy of Drosophila funebris (Fab.) is illustrated in Plate 97, figs. 1–5, and the terms used in describing the characters in the figures are those used in the descriptions of the species in this paper. In addition, the following explanations are required. In dealing with the arista, the hairs of the plumosity are referred to as branches and the apex of the aristal axis which forms a terminal fork with the ultimate hair is always included in the count. The first oral bristle only is termed the vibrissa and the one next to it, if present, is called the second oral bristle. The number of rows of acrostichal hairs is taken as those between or just anterior to the pair of anterior dorso-centrals. The sterno-index (Kikkawa and Peng, 1938) is the length of the anterior sternopleural divided by the length of the posterior sternopleural. Wing indices are as follows:

Costal index: length of second section of the costal vein (between apices of first and second longitudinal veins) divided by length of the third section (between apices of second and third veins).

Fourth vein index: length of distal section of the fourth vein divided by length of its third section (between the two cross veins).

4c index: length of third section of the costal vein divided by length of third section of the fourth vein.

5x index: length of the distal section of the fifth vein divided by length of the posterior cross vein.

Many characters show rather extensive variation and where possible mean values of measurements, indices and numbers are given.

Key to Species
1. Mesonotum distinctly marked with spots or stripes 2
Mesonotum not distinctly marked 4
2. Mesonotum grey with dark brown spots at base of each hair or bristle 3
Mesonotum yellowish-brown with dark brown longitudinal stripes busckii
3. Costa darkened at distal break repleta
Costa not darkened at distal break hydei
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4. Costal index less than 3.0 5
Costal index greater than 3.0 6
5. Vertical diameter of eye about 7 or 8 times width of check in same axis; genital arch of male with large posterior process simulans
Vertical diameter of eye about 5 times width of cheek in same axis; genital arch of male with small posterior process melanogaster
6. Prothoracic femora with row of short bristles on ventral surface brouni
Prothoracic femora without short stout bristles funebris

Drosophila busckii Coquillet

  • D. busckii Coquillet. 1901. Ent. News., Vol. 12, p. 18.

  • D. rubrostriata Becker. 1908. Mitt. Zool. Mus., Vol. 4, p. 155.

  • D. plurilineata Villeneuve, 1911. Wien. Ent. Zeit., Vol. 30, p. 38.

Male and female:

General: A yellowish-brown species with distinctive dark brown bands on thorax. Length of body, 2·0–2·5 mm. Length of wing. 2·0–2·5 mm.

Head: Arista with about nine branches and a row of about six short branches on inner side of main axis; generally blackish, proximal segment of main axis yellowish-brown. Third segment of antennae dark brown; second segment yellowish-brown with about two bristles on anterior edge. Front predominantly yellowish-brown and silvery-grey. Ocellar triangle almost black, slightly raised. Ocelli clear or light-yellow. Frontal vitta silvery-grey about ocellar triangle, light yellow anteriorly and shining yellow elsewhere. Frontal orbits silvery-grey but light yellow anteriorly. Middle fronto-orbital bristle about two-thirds anterior orbital, which is just over three-quarters of the posterior orbital; middle orbital lateral to and level with, just posterior to or anterior to anterior orbital. One or two small hairs posterior to anterior and middle orbital and a row of hairs extending anteriorly from these two bristles along frontal orbits. Two groups of about eight hairs near middle of anterior frontal vitta. Face light yellow. Carina narrow, not sulcate. Second oral bristle about seven-eighths length of vibrissa. About three strong bristles at each posterior ventral corner of head about one-half length of vibrissa. Eyes dull greyish-red or dark red in dried specimens. Vertical diameter of eye four times width of cheek in same axis. Cheeks light yellow or almost white. Proboscis yellow. Palpi with one subapical bristle. Haustellum with several long slender bristles.

Thorax: Light yellowish-brown. A dark brown band on mid-dorsal line of mesonotum extending from anterior margin to region of anterior dorsocentrals, where it bifurcates and may extend to posterior margin of mesonotum, uniting with other bands; a similar band on each dorsocentral line usually arising posterior to anterior origin of median band and ending before posterior margin of mesonotum; a lateral band arising near humerus and extending to dorsal wing base and occasionally a shorter, lighter band between this and the dorsocentral band; a darker wide band arising on propleura and extending to just below base of wing or across dorsal mesopleura to haltere; a short band across the sternopleura and a dark patch at postero-ventral corner of hypopleura. Scutellum bare with light yellowish-brown edge merging into a central darker brown area. Acrostichal hairs in eight rows. Several hairs in prescutellar region often slightly enlarged. Two pairs of dorso-

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centrals; no enlarged hairs in dorsocentral line. Two pairs of marginal scutellars, anterior pair parallel or slightly convergent, posterior pair crossed. Two humerals and occasionally a third weaker bristle dorsally. Two sternopleurals and a row of hairs extending from between these bristles ventrally down sternopleura to a point anterior of base of mesothoracic coxa; sterno-index about 0·3. Legs uniformly yellowish-brown. Prothoracic femora with one dorsal bristle at apical quarter; two or three strong posterodorsals about mid-femora and about three strong posteroventrals on apical two-thirds. Prothoracic tibia with a small apical bristle and about five comb-like transverse rows of hairs directed apically and on ventral surface of apical half of segment. Prothoracic tarsus with similar but narrower combs; with some recurved hairs in male and few such hairs in female; no sex combs in male; first segment about two-thirds length of first segment of mesothoracic tarsus; second segment not shortened or stouter. Mesothoracic tibia with apical and weak preapical bristles. Metathoracic tibia with preapical bristle. Metathoracic tarsus with no distinct bristles at base of first segment. Wings clear (Plate 98, fig. 6). Third costal section with thick, short bristles extending to basal fifth. Pair of long bristles at distal costal break and costa not darkened at this region. Costal index about 3·1; fourth vein index about 2·0; 4c index about 0·9.; 5x index about 2·0. Halteres yellowish-brown with the two basal segments partly dark brown.

Abdomen: Yellow. Each tergite with posterior blackish-brown band, wider on posterior segments, interrupted mid-dorsally, narrowed laterally and terminated before reaching lateral margin of segment and reappearing at posterior edge of the incurved ventral portion of tergite. Male hypopygium as shown in Plate 99, fig. 16, and female ovipositor plate as in Plate 99, fig. 19.

Locality of specimens examined: Palmerston North: Mar. 1930, Aug. 1931, W. Cottier. Owairaka, Auckland: Sept. 1940, Mar. 1941, Mar. 1942, D. Spiller; July 1943, C. Reid; Jan. 1949, R. A. Harrison. Wallaceville: 1944, L. K. Whitten; Mt. Albert; Oct. 1948, W. Barnard. Avondale: Aug. 1949, R. A. Harrison. Mt. Eden: April 1949, R. A. Harrison. Brown's Bay: Jan.-Sept. 1950, R. A. Harrison. Waitakere Ranges: Feb. 1950, M. Knight. Mangere: Jan. 1950, K. P. Lamb. Nelson: Feb. 1950, R. A. Harrison. Total specimens examined: 220.

This cosmopolitan species is very common in New Zealand. The distribution as at present known extends from Auckland to Nelson and thus includes both islands. The species breeds readily on artificial medium in the laboratory. In the field it has been taken on rotting potatoes, rock melon, swede, apple, orange, waste rotting tobacco, and in sour milk.

Drosophila repleta Wollaston

  • D. repleta Wollaston. 1858. Ann. Mag. Nat. Hist., Vol. 41, p. 117.

  • D. punctulata Loew. 1862. Berlin Ent. Zeit., Vol. 6, p. 232.

  • D. adspersa Mik. 1886. Wien. Ent. Zeit., Vol. 5, p. 328.

Male and female:

General: A dark brown species with light grey mesonotum with dark brown spots at base of each bristle and hair, Body length about 2·5 mm, Wing length about 2·5 mm.

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Head: Arista with about seven branches and a row of about five short branches on inner edge of main axis; proximal segment of main axis and proximal portion of distal segment yellowish-brown, otherwise black. Third segment of antennae dark brown, lighter beneath; second segment yellowish-brown or light reddish-brown with a dark brown patch dorsally and with three bristles, one median and two apical. Front predominantly dark reddish-brown and silvery-grey. Ocellar triangle almost black and distinctly raised above level of front. Ocelli reddish. Frontal vitta dark reddish-brown; a narrow area lighter in colour in median line extending from ocellar triangle to lunule. Frontal orbits silvery-grey posteriorly and about region of fronto-orbital bristles and reddish-brown anteriorly. Each fronto-orbital bristle arising from a dark spot. Middle orbital one half length of anterior orbital, which is equal to posterior orbital. Middle orbital closer to anterior orbital than posterior orbital and lateral to these bristles. Row of about seven hairs extending anteriorly along orbit from anterior orbital. An irregular row of about eight hairs extending from anterior orbital to mid-point of lunule. Face brown or dark brown with darker areas. Carina broad ventrally, sunken well below level of face dorsally and slightly sulcate ventrally. Second oral bristle about half length of oral vibrissa. Three bristles at posterior ventral corner of head equal in length to vibrissa. Eyes dark red in dried specimens. Vertical diameter of eye about five times width of cheek in same axis. Cheeks brown. Proboscis predominantly brown. Rostrum dark brown. Palpi yellowish-brown and with four thin bristles evenly spaced on lateral margin, the apical bristle the longest. Haustellum with two pairs of elongate slender bristles posteriorly, one pair at midtheca and the other at apex.

Thorax: Light grey dorsally with each bristle and hair arising from a dark brown spot; these spots often fusing together to form larger dark brown areas; dark brown laterally and ventrally. Scutellum with a slight yellowish-brown margin merging into a dark brown central area. Acrostichal hairs in eight rows. Some enlarged hairs in prescutellar region. Two pairs of dorsocentrals, and in the same line as these and anteriorly there are several enlarged hairs. Two pairs of marginal scutellars, both pairs convergent and the posterior pair crossed. Three humerals, the middle bristle strongest and the dorsal weakest. Two sternopleurals; between these a clump of hairs, one or two of which may be enlarged and a row of hairs extending ventrally from this clump down the sternopleura; sterno-index about 0·8. Legs reddish-brown; prothoracic coxa darker. Prothoracic femora with one dorsal bristle at apical quarter; about four evenly spaced posterodorsal bristles on basal two-thirds, basal bristle weakest; about six evenly spaced postero-ventral bristles, basal one weakest. Prothoracic tibia with apical and preapical bristles and about seven comb-like transverse rows of hairs directed apically and on ventral surface of apical half of segment. Prothoracic tarsus with no long recurved hairs in either sex; no sex comb in male; first segment about two-thirds length of corresponding segment of mesothoracic tarsus and not stouter. Mesothoracic tibia slightly darker basally and with apical and pre-apical bristles. Metathoracic tarsus without basal bristles but with

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combs similar to those on prothoracic tibia and tarsus. Wings (Plate 98, fig. 9) clear. Third costal section with thick, short bristles extending to basal half. Pair of small bristles on costa at distal costal break and costa is darker at this region. Costal index about 3·0; fourth vein index about 1·7; 4c index about 0·8; 5x index about 1·3. Halteres light reddish-brown.

Abdomen: Yellowish-brown tergites each with wide dark brown bands posteriorly. These bands are interrupted mid-dorsally and extend over whole width of tergite. A yellowish-brown area near anterior corner of the lateral margin of each tergite. Male hypopygium is shown in Plate 99. fig. 13, and female ovipositor plate in Plate 99, fig. 20.

Locality of specimens examined: Auckland: April 1941, D. Spiller. Avondale: Dec. 1948, R. A. Harrison. Paihia, Bay of Islands: March 1949, K. P. Lamb. Total specimens examined: 13.

This cosmopolitan species has not been found very frequently in New Zealand as yet and appears to be less common than D. hydei. Sturtevant (1921) suggested it was possible that D. marmoria Hutton is a synonym of D. repleta, but the type specimen of D. marmoria has been examined and found to be distinct.

Drosophila hydei Sturtevant

  • D. hydei Sturtevant. 1921. Carnegic Inst. Wash. Publ. No. 301, p. 101.

Male and female:

General: A dark brown species with light grey mesonotum and dark brown spots at base of each hair and bristle. Body length about 2·5 mm. Wing length about 2·5 mm.

Head: Arista with about seven branches and about five short branches on inner edge of main axis; proximal segment of main axis yellowish-brown, rest of arista black. Second and third segments of antennae dark brown, but yellowish-brown beneath. Second segment with three bristles, strongest mid-anteriorly and two smaller ones apically. Front predominantly dark reddish-brown with some lighter grey areas. Ocellar triangle almost black and slightly raised above general level of front. Ocelli clear or reddish. Frontal vitta dark reddish-brown. Frontal orbits silvery-grey posteriorly and also where fronto-orbital bristles arise and dark brown or brown anteriorly. A dark spot at base of each bristle on orbits and these often merged together in the case of the posterior orbital and verticals. Middle fronto-orbital bristle half length of anterior orbital, which is equal to posterior orbital; closer to anterior orbital than posterior and lateral to them. An irregular row or group of about eight hairs on anterior frontal vitta extending from mid-lunule towards anterior orbital. Row of about nine hairs extending anteriorly along orbit from middle orbital. Face brown. Carina prominent, raised ventrally, almost level with front dorsally and sulcate. Second oral bristle about half length of vibrissa. Three bristles at posterior ventral corner of head about two-thirds length of vibrissa. Eyes dark red in dried specimens. Vertical diameter of eye about 4·5 times width of cheek in same axis. Cheeks yellowish-brown. Proboscis predominantly yellowish-brown. Rostrum darker, Palpi with one strong apical bristle. Haustellum

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with two pairs of elongate slender bristles posteriorly; apical pair shorter.

Thorax: Light grey dorsally with dark brown spots at base of each hair or bristle which may fuse to form larger dark areas; laterally reddish-brown and lighter yellowish-brown ventrally. Scutellum dark reddish-brown sometimes lighter at margin and with no distinct markings. Acrostichal hairs in eight rows. No enlarged hairs in prescutellar region. Two pairs of dorsocentrals and in same line as these and anterior to them some enlarged hairs. Two pairs of marginal scutellars, anterior pair convergent, posterior pair crossed. Three humerals, middle bristle strongest and dorsal weakest. Two sternopleurals, a group of hairs between and below them and a row of hairs extending ventrally down sternopleura; sterno-index 0·7. Legs predominantly yellowish-brown. Prothoracic coxae yellowish-brown. Prothoracic femora with one dorsal bristle at apical quarter; about four bristles postero-dorsally, the basal one weakest; about six postero-ventrally, basal weakest; one small posterior basal and two weak posterior apicals. Prothoracic tibia with apical and preapical bristles and about seven comb-like transverse rows of hairs directed apically and on ventral surface of apical half of segment. Prothoracic tarsus with many short and some long slender recurved hairs in male, but not in female; no sex comb in male; first segment in both sexes about two-thirds length of corresponding segment in mesothoracic tarsus and not stouter. Mesothoracic tibia with apical and preapical bristles. Metathoracic tibia with preapical bristle. Metathoracic tarsus without basal bristles on first segment, but with combs of hairs as on prothoracic tibia. Wings clear (Plate 98, fig. 10). Third costal section with thick, short bristles extending to basal half. Pair of bristles at distal costal break and costa not darkened at this region. Costal index about 3·5; fourth vein index about 1·75; 4c index about 0·75; 5x index about 1·1. Halteres yellowish-brown with the two basal segments darker on anterior surfaces.

Abdomen: Yellowish-brown with dark brown bands posteriorly on each tergite. These bands are interrupted mid-dorsally, narrowed slightly before reaching lateral margin of segment, but covering whole width at incurved ventral portion of tergite. This interruption and narrowing of the band is not so pronounced posteriorly. Male hypopygium is shown in Plate 99, fig. 14, and the female ovipositor plate in Plate 99, fig. 21.

Locality of specimens examined: Owairaka, Auckland: July 1940, D. Spiller; Nov. 1949, R. A. Harrison. Sandringham: May 1941, G. Chamberlain. Paihia. Bay of Islands: March 1949, K. P. Lamb. Mt. Albert: Oct. 1948, W. E. Barnard. Avondale: Dec. 1948, 1949, R. A. Harrison. Mt. Eden: April 1949, R. A. Harrison. Mangere: Nov. 1949. Jan., Feb. 1950, K. P. Lamb. Brown's Bay: Nov. 1949, April, July, Aug. 1950, R. A. Harrison. Total specimens examined: 46. This species appears to be common in New Zealand and has been taken frequently on decaying vegetation and from rotting fruit.

Drosophila marmoria Hutton

  • D. marmoria Hutton. 1901. Trans. N.Z. Inst., Vol. 33, p. 91.

The type specimen of this species has been examined; it is in a bad state of preservation and no paratypes are available. It keys down

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to D. hydei, but cannot with certainty be regarded as being identical with that species because many structures are missing or partially destroyed.

Type: Female; Auckland. H. Suter.

Location of type: Canterbury Museum, Christchurch, New Zealand.

Drosophila simulans Sturtevant

  • D. simulans Sturtevant. 1919. Psyche, Vol. 26, p. 153.

Male and female:

General: A yellowish-brown species. Length of body, 2 mm. Length of wing, 2 mm.

Head: Arista with about 10 branches and about seven short branches on inner edge of main axis; proximal segment of main axis yellowish-brown, distal segment black. Third segment of antennae light brown; second segment yellowish-brown with two longer bristles on anterior edge. Front yellowish-brown. Ocellar triangle brown, slightly raised above front. Ocelli whitish. Frontal vitta yellowish-brown. Frontal orbits yellowish-brown and slightly raised at region of fronto-orbital bristles and brown at this region. Middle fronto-orbital bristle about half length of anterior orbital, which is about seven-eighths length of posterior orbital. Middle orbital lateral to and level with or posterior to anterior orbital. A row of about four hairs between mid-point of lunule and anterior orbital. A row of about five hairs extending from middle orbital outside anterior orbital anteriorly along orbit. Face light yellowish-brown. Carina prominent, narrow dorsally, not sulcate. Second oral bristle equal in length to oral vibrissa. Three or four bristles at postero-ventral corner of head about half length of vibrissa. Eyes reddish-brown in dried specimens. Vertical diameter of eye about seven or eight times width of cheek in same axis. Cheeks yellowish-brown. Proboscis predominantly yellowish-brown. Palpi yellow with several bristles apically. Haustellum with long slender bristles posteriorly, middle pair strongest.

Thorax: Light reddish-brown dorsally, lighter ventrally, no distinctive pattern. Scutellum same colour as mesonotum. Acrostichal hairs in eight rows. No enlarged hairs in prescutellar region. Two pairs of dorsocentrals and no enlarged hairs in same line anteriorly. Two pairs of marginal scutellars; anterior pair convergent or nearly parallel; posterior pair crossed. Two numerals, ventral one stronger and sometimes one small bristle dorsally. Two large sternopleurals and one small bristle between these two; a row of hairs extending ventrally down sternopleura from sternopleurals; sterno-index 0·5. Legs shining yellowish-brown, tarsal segment not darkened. Prothoracic femora with one dorsal bristle at apical quarter; two strong bristles about mid-way and a weaker basal one on postero-dorsal surface, distal bristle the stronger; about seven bristles on postero-ventral surface, apical four the strongest. Prothoracic tibia with small apical and preapical bristles and about seven comb-like transverse rows of hairs directed apically and on ventral surface of apical half of segment. Prothoracic tarsus in male with sex comb on anterior surface of first segment consisting of a conspicuous row of about ten shining black bristles closely opposed to each other; in both sexes basal segment about two-thirds

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size of corresponding segment of mesothoracic tarsus and not stouter. Mesothoracic tibia with apical and preapical bristles. Metathoracic tibia with weak preapical bristle only. Metathoracic tarsus with pair of small bristles proximally on basal segment and combs of hairs as on prothoracic tibia. Wings clear (Plate 98, fig. 7). Third costal section with thick, short bristles extending to basal one third. Pair of strong bristles at distal costal break; costa not darkened at this area. Costal index about 2·25; fourth vein index about 2·5; 4c index about 1·3; 5x index about 2·0. Halteres yellowish-brown.

Abdomen: Black or dark brown posteriorly and yellowish-brown anteriorly. Male darker than female. Each tergite with posterior dark brown band which is wide mid-dorsally and narrowed laterally sometimes disappearing before reaching lateral margin of tergite. Male hypopygium is shown in Plate 99, fig. 11, and the female ovipositor plate in Plate 99, fig. 18.

Locality of specimens examined: Owairaka, Auckland: Oct. 1940, D. Spiller; April 1944, C. Burton. Remuera: April 1941, D. Spiller. Sandringham, Oct. 1943, G. Chamberlain. Auckland: Aug. 1943, Orchard Instructor, Department of Agriculture. Mangere: Jan. 1950, K. P. Lamb. Mt. Albert: Oct. 1948, W. Barnard. Avondale: Jan. 1950, R. A. Harrison. Waitakere Ranges: Feb. 1950, M. Knight. Total specimens examined: 217.

This species is abundant in the Auckland area and appears to be far more common than the closely allied species Drosophila melanogaster. It has been bred from pineapple imported from Queensland and bananas from Raoul Island, and it is probably being continually introduced into New Zealand with imported fruit. It breeds well in the laboratory and has been bred from rotting fruit of many kinds as well as decaying maize cobs and potatoes.

Drosophila melanogaster Meigen

  • D. melanogaster Meigen. 1830. Syst. Beschr., Vol. 6, p. 85.

  • D. nigriventris Zetterstedt. 1847. Dipt. Scand., Vol. 6, p. 2557.

  • D. ampelophila Loew. 1862. Berlin Ent. Zeit., Vol. 6, p. 231.

  • D. uvarum Rondani. 1875. Bull. Com. Agr. Parm.

The description of this species is identical with that of D. simulans Sturtevant given above except for the following: The cheek is broader; the vertical diameter of eye is about five times width of cheek in same axis. The male hypopygium is different (Plate 99, fig. 12); the clasper is different and the posterior process on the genital arch is very much smaller than that on the genital arch of D. simulans.

Locality of specimens examined: Oratia: Dec. 1949, R. A. Harrison. Brown's Bay: Oct. 1949, R. A. Harrison. Green Lane: March 1949, K. P. Lamb. Waitakere Ranges: Feb. 1950, M. Knight. Mangere: Jan. 1950, K. P. Lamb. Total specimens examined: 14.

The two species D. simulans and D. melanogaster are readily separated on the width of the cheeks, and in living males at least, the hypopygium offers an extra means of differentiation. In dried specimens it is usually necessary to relax and clear the male abdomen before these characters can be easily seen.

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Drosophila brouni Hutton

  • D. brouni Hutton. 1901. Trans. N.Z. Inst., Vol. 33, p. 91.

  • D. immigrans Sturtevant. 1921. Carnegie Inst. Wash., Publ. No. 301, p. 83. (New synonymy.)

Male and female:

General: A yellowish-brown species. Length of body, 3·0 mm. Length of wing, 3·0 mm.

Head: Arista with about eleven branches and a row of about seven short branches on inner edge of main axis; proximal segment of main axis yellowish-brown, distal segment black. Third segment of antennae brown, lighter beneath; second segment yellowish-brown usually with two but sometimes with up to four bristles on apical half anteriorly. Front predominantly reddish or yellowish-brown. Ocellar triangle dark brown, slightly raised. Ocelli usually light yellow. Frontal vitta yellowish-brown, darker in some specimens. Frontal orbits yellowish to reddish-brown, but yellowish-brown surrounding orbital bristles. Middle fronto-orbital bristle about half anterior orbital, which is equal to posterior orbital. Middle orbital in line with or lateral to the other two orbitals and midway between them or closer to anterior orbital. Row of about five hairs on frontal orbit extending from middle orbit outside anterior orbital to level with base of antennae. About four hairs in an irregular row between anterior orbital and mid-point of frontal lunule. Face yellowish-brown. Carina prominent, narrow dorsally, but wider ventrally where it merges into the epistoma; not sulcate. Second oral bristle about three-quarters length of oral vibrissa. Two strong bristles at each posterior-ventral corner of head about two-thirds length of vibrissa. Eyes dark red in dried specimens. Vertical diameter of eye about 4·5 times width of cheek in same axis. Cheeks yellowish-brown. Proboscis predominantly yellowish-brown. Palpi lighter than proboscis and with three bristles apically. Haustellum with several pairs of long slender bristles.

Thorax: Yellowish-brown dorsally, lighter ventrally and with no distinct pattern. Scutellum also yellowish-brown with occasionally a yellow streak on mid-longitudinal line. Acrostichal hairs in eight rows. No enlarged hairs in prescutellar region. Two pairs dorsocentrals and no enlarged hairs in same line anteriorly. Two pairs marginal scutellars; anterior pair parallel or convergent; posterior pair crossed. Two humerals. Three sternopleurals; a clump of a few hairs immediately ventral to these bristles and a row of hairs extending ventrally down sternopleura; sterno-index about 0·6. Legs yellowish-brown, tarsal segments a shade darker. Prothoracic femora with one dorsal bristle at apical quarter; three or four postero-dorsal bristles on basal three-quarters; about six evenly spaced postero-ventrals, if some are missing the gaps are usually on basal half of segment; one thin posterior basal and two posterior preapicals. Row of about nine to twelve short, stout bristles on apical half ventrally. Prothoracic tibia with apical and preapical bristles, and about ten comb-like transverse rows of hairs, apically directed and on ventral surface of apical half of segment. Prothoracic tarsus in male with long recurved hairs especially on first segment; a massive brush of thin hairs on ventral surface of first and second segments; no sex combs, first segment about half length of

Picture icon

Drosophila funebris (Fabricius)
Fig. 1—Chaetotaxy of thorax and head. Dorsal aspect approx. × 25.
Fig. 2—Chaetotaxy of thorax and head. Lateral aspect approx. × 25. DC 1, 2; Dorsocentral; 1 anterior, 2 posterior. FO 1, 2, 3; Fronto-orbital: 1 anterior, 2 middle, 3 posterior. HU; Humeral. NO 1, 2; Notopleural: 1 anterior, 2 posterior, OB; Second oral bristle. OC; Ocellar. OV; Oral vibrissa. PA; Post-alar. PS: Presutural. PV: Post-vertical. SA: Supra-alar [ unclear: ] SC [ unclear: ] 1, 2, Scu [ unclear: ] ellar; 1 anterior, 2 posterior. SP; Sterno-pleural [ unclear: ] V; Vertical.
Fig. 3—Wing. Approx. × 27. 1–6; First to sixth longitudinal veins. AC; Anterior cross vein. BC 1, 2; Basal cell; 1 first basal, 2 second basal. C; Costal vein. DC; Diseal cell. PC; Posterior cross vein.
Fig. 4—Male hypopygium. Approx. × 150. AP: Anal plate. CL; Clasper. GA: Genital arch.
Fig. 5—Female ovipositor plate. × 150.

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Wings of Drosophila species. Approx. × 25
Fig. 6—D. busckii Coquillet
Fig. 7—D. simulans Sturtevant
Fig. 8—D. brouni Hutton
Fig. 9—D. repleta Wollaston
Fig. 10—D. hydei Sturtevant

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Male hypopygium of Drosophila species
Fig. 11—D. simulans. Approx. × 110
Fig. 12—D. melanogaster. Approx. × 110
Fig. 13—D. repleta. Approx. × 80
Fig. 14—D. hydei. Approx. × 80
Fig. 15—D. brouni. Approx. × 110
Fig. 16—D. busckii. Approx. × 110
Female ovipositor plates of Drosophila species. Approx. × 100
Fig. 17—D. brouni
Fig. 18—D. simulans
Fig. 19—D. busckii
Fig. 20—D. repleta
Fig. 21—D. hydei

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corresponding segment of mesothoracic tarsus and stouter. Prothoracic tarsus in female without recurved hairs and brush; first segment with combs as on tibia and about two-thirds length of corresponding segment of mesothoracic tarsus and not stouter. Mesothoracic tibia with apical and preapical bristles. Metathoracic tibia with preapical bristle. Metathoracic tarsus with a pair of bristles at base of first segment and combs similar to those on prothoracic tibia and tarsus. Wings (Plate 98, fig. 8) clear with slight fogging at posterior cross vein and apices of second, third and fourth longitudinal veins. Third costal section with thick, short bristles extending to basal third. One strong bristle only at distal costal break and costa not darkened at this region. Costal index about 4·2; fourth vein index about 1·2; 4c index about 0·5; 5x index about 1·0. Halteres light yellowish-brown.

Abdomen: Yellowish-brown with a blackish-brown band on posterior region of each tergite; this band wider on distal tergites. Male hypopygium is shown in Plate 99, fig. 15, and female ovipositor plate in Plate 99, fig. 17.

Type: Female; Auckland, H. Suter.

Location of type: Canterbury Museum, Christchurch, New Zealand.

Homoeotypes: Males and females located at Plant Diseases Division, Department of Scientific and Industrial Research, Auckland, New Zealand.

Locality of specimens examined: Palmerston North: Mar. 1930, W. Cottier. Nelson: May 1921, A. Philpott; April 1944, E. E. Walker. Owairaka, Auckland; Sept., Oct. 1940, D. Spiller; July 1943, C. Reid; Nov. 1948, D. McKenzie; July–Sept. 1950, R. A. Harrison. Brown's Bay: Sept. 1948, May–Dec. 1949, Jan.–Sept. 1950, R. A. Harrison. Green Lane: Sept., Dec. 1948, June 1949, K. P. Lamb. Remuera: April 1941, D. Spiller. Avondale: Dec. 1948, Sept. 1949, July–Sept. 1950, R. A. Harrison. Total specimens examined: 696.

I have examined the type of D. brouni Hutton and find that it is identical with D. immigrans Sturt. The name D. brouni has priority and D. immigrans becomes, therefore, a synonym of D. brouni. The type specimen is a female and is in a state of excellent preservation. There are no paratypes. In the original description (Hutton, 1901) the arista is stated to have 10 long hairs. When the tip is considered to consist of two branches the number of branches is eleven. The above description of this species is based on the type specimen as well as on other specimens from localities recorded above. The type bears a locality label “Auck.” and not Auckland Islands as recorded by Sturtevant (1921).

This species appears to be the commonest Drosophilid found in New Zealand. It breeds readily in the laboratory and has been bred from many kinds of decaying fruit as well as being taken on fleshy fungi.

Drosophila funebris (Fabricius)

  • Musca funebris Fabricius. 1787. Mant. Ins., Vol. 2, p. 345, no. 33.

  • D. clarkii Hutton. 1901. Trans. N.Z. Inst., Vol. 33, p. 91. (New synonymy.)

Male and female:

General: A yellowish or reddish-brown species. Length of body, 3·0 mm. Length of wing, 3·0 mm.

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Head: Arista with about twelve branches and a row of about eleven short branches on inner edge of main axis; proximal segment of axis yellowish-brown, distal segment black. Third segment of antennae dark brown; second segment dark brown but lighter beneath and with with one median and one or two apical bristles. Front light reddish-brown. Ocellar triangle a shade darker than front and raised slightly. Ocelli whitish or light red. Frontal vitta reddish-brown. Frontal orbits reddish-brown; the area about fronto-orbital bristles slightly raised. Middle fronto-orbital about half length of anterior orbital, which is half length of posterior orbital. Middle orbital almost level with and outside anterior orbital. Two convergent sets of about ten small hairs on anterior frontal vitta. A row of about six small hairs extending anteriorly along orbit from middle orbital and outside anterior orbital. One or two small hairs posterior to middle orbital. Face yellowish-brown. Carina prominent, flattened and broad ventrally; not sulcate. Second oral bristle about three-quarters length of oral vibrissa. Two or three bristles at posterior ventral corner of head about two-thirds length of vibrissa. Eyes dark red in dried specimens. Vertical diameter of eye about five times width of cheek in same axis. Cheeks yellowish-brown. Proboscis yellowish-brown. Palpi with about four bristles, the apical ones being strongest. Haustellum with several pairs of long slender bristles posteriorly.

Thorax: (Plate 97, figs. 1 and 2.) Reddish-brown, mesonotum without any pattern. Scutellum a shade darker than mesonotum. Acrostichal hairs in eight rows. No enlarged hairs in prescutellar region. Two pairs dorsocentrals and several hairs in same longitudinal line, anteriorly, enlarged. Two pairs marginal scutellars; anterior pair convergent or nearly parallel; posterior pair convergent and crossed. Two humerals with sometimes one extra smaller dorsal bristle. Two large sternopleurals and usually one or sometimes two smaller bristles between them; if two, then the posterior one is the larger. Some hairs ventral to these bristles and a row of hairs extending ventrally down sternopleura; sterno-index 0·6. Legs uniformly shining yellowish-brown. Prothoracic femora with one dorsal bristle at apical quarter; two bristles postero-dorsally, one at apical third and one basally; three strong bristles postero-ventrally within apical two-thirds and sometimes one or two weaker bristles basally; one weak posterior bristle at apex. Prothoracic tibia with apical and preapical bristles and about nine comb-like transverse rows of hairs directed apically and on ventral surface of segment. Prothoracic tarsus with similar but narrower combs; few recurved hairs; no sex comb in male; first segment about two-thirds length of corresponding segment of mesothoracic tarsus and not stouter than second segment. Mesothoracic tibia with apical and preapical bristles. Metathoracic tibia with preapical bristle. Metathoracic tarsus with combs as on prothoracic tibia. Wings (Plate 97, fig. 3) clear. Third costal section with thick short bristles extending to basal half. Pair of short bristles at distal costal break; costa not darkened at this region. Costal index about 3·5; fourth vein index about 1·3; 4c index about 0·6; 5x index about 1·0. Halteres yellowish-brown.

Abdomen: Yellowish-brown. Tergites with a posterior brown or dark brown band. In males these bands, especially on posterior tergites,

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are very dark and wide and appear to cover whole tergite. In female, bands on anterior tergites are often interrupted mid-dorsally. Male hypopygium is shown in Plate 97, fig. 4, and female ovipositor plate in Plate 97, fig. 5.

Locality of specimens examined: Dunedin: April 1935, W. Cottier. Auckland: Jan. 1938, W. Cottier; April 1943, Orchard Instructor, Department of Agriculture. Rangiora: Feb. 1944, Orchard Instructor, Department of Agriculture. Owairaka, Auckland: March 1942, D. Spiller; Jan. 1950, R. A. Harrison. Total specimens examined: 63.

I have examined the type and the three paratypes of D. clarkii Hutton and find them identical with D. funebris (Fab.). Since the name D. funebris has priority, D. clarkii must therefore be reduced to a synonym of D. funebris.

This species is cosmopolitan and is common in New Zealand. It breeds readily in the laboratory, has been bred from many types of decaying fruit, and has also been taken on beeswax in a honey house. It has been bred from pineapples imported from Queensland and bananas from Raoul Island and is probably being continually introduced into New Zealand with imported fruit.

References

Cottier, W., 1933. N.Z. Journ. Sci. and Tech., Vol. 4, pp. 142–145.

Fallen, C. F., 1823. Diptera Sueciae, Geomyzides. Pt. 2, p. 4.

Hutton, F. W., 1901. Trans. N.Z. Inst., Vol. 33, pp. 91–92.

Kikkawa, H., and Peng, F. T., 1938. Jap. Journ. Zool., Vol. 7, pp. 507–552.

Miller, David, 1921. N.Z. Journ. Sci. and Tech., Vol. 3, p. 302.

Sturtevant, A. H., 1921. Carnegie Inst. Wash. Publ. No. 301, 150 pp.