Drosophila (Sophophora) bunnanda, Schiffer, Michele & Mcevey, Shane F., 2006

Schiffer, Michele & Mcevey, Shane F., 2006, Drosophila bunnanda — a new species from northern Australia with notes on other Australian members of the montium subgroup (Diptera: Drosophilidae), Zootaxa 1333, pp. 1-23 : 9-13

Drosophila (Sophophora) bunnanda sp. nov.

= “ Drosophila (Sophophora) species B” of McEvey 1993, p. 162. = “northern D. serrata ” of Kelemen & Moritz 1999

= “cryptic species” of Schiffer et al. 2004

= “ Drosophila species X” of Kellett & McKechnie 2005 = “ D. species x ” Kellermann et al. 2006

not Drosophila (Sophophora) sp. cf. jambulina of Bock 1976, p. 269.

Type material. Type culture founding females from vicinity of Lake Placid, Queensland (LPX), collected 21 Mar 2001, culture maintained at La Trobe University, Melbourne. Holotype ♂ in AM, registered K118082: Qld Lake Placid, 16°52’04”S 145°40’23”E, r’forest, ex strain LPX, founded Mar 2001, [pinned] 27.ii.2002, M. Schiffer. Paratypes (26 ♂♂, 13 ΨΨ): same data as holotype but registered as follows: 13 ♂♂ AM K104870–73, K10549 –53, K105055–56, K118134–35, 5 ΨΨ AM K118136–40; 21 same data as holotype, but pinned 20.ii.2002: 1♂ AM K104864, 3 ♂♂ ANIC (Reg. 16475–16477), 3 ♂♂ UQIC (Reg. 16478–16480), 3 ♂♂ QM (Reg. 16481–16483), 3 ♂♂ AMNH (Reg. 16484–16486), 4 ΨΨ AM K104865–66, K104868–69, 1 Ψ ANIC (Reg. 16491), 1 Ψ UQIC (Reg. 16492), 1 Ψ QM (Reg. 16493), 1 Ψ AMNH (Reg. 16494). Partial ND5 sequence data of a type culture specimen has previously been submitted to GenBank, Accession Number: AY345231 ( Schiffer et al. 2004).

Other material examined. 1 ♂ Qld, Heathlands, Bertie Creek pump, 11°46’S 142°36’E, fruit, 10 Mar 1992, S.F. McEvey, Reg. 9141, AM. 1 ♂ Qld, Heathlands, Doublemouth Creek, 11°37’S 142°49’E, swept, 22 Mar 1992, S.F. McEvey, Reg. 10129, AM. Holotype of Drosophila serrata , AM K73197 (formerly held in SPHTM), ♂, Eidsvold, Qld [25.4°S], 2 April 1924, Bancroft. Holotype of Drosophila birchii , AM K70574 ♂ [rain forest of the Crystal Cascade Park ( Dobzhansky & Mather 1961)] Cairns, Qld, 1961, Dobzhansky & Mather, and allotype with same data, AM K70575 . 2 ♂♂ of Bock’s (1977) “ Drosophila sp cf jambulina ” with label-data: Townsville Qld, banana bait, Jan/ Feb 1976, I.R. Bock, Reg. 21753–21754. Drosophila kikkawai : 5 ΨΨ ex culture, Townsville, Qld, baited Feb 1976, I.R. Bock; 23 (both sexes) Townsville, Qld, banana bait, Jan/ Feb 1976, I.R. Bock; 16 ♂♂ and 9 ΨΨ Qld Cairns, 16°52’44”S 145°44’40”E, urban, ex strain [La Trobe University] FBK, founded Aug 2001, 20.ii.2002, Schiffer.

Numerous additional field observations of this species were made at the following localities (there are no museum voucher specimens, all determined by Schiffer, collected by Schiffer unless otherwise indicated): “Joleka”, Townsville (Mar 2001, 2002); Kirrama (Oct 1999; Mar 2001, 2002); Lake Barrine (Mar 2001, 2002); Gordonvale (Oct 1999); Goomboora Park (Cairns) (Sep 2003, Dean); Kamerunga Island (Nov 2002); Lake Placid (Oct 1999; Mar 2000, 2001, 2002; Nov 2002); Lake Placid (Nov 2000, Mitrovski); Lake Placid (Aug 2001, Hallas); Lake Placid (Sep 2003, Dean); Mossman Gorge (Oct 1999, Blows and Kelemen); Good Shepherd (Mossman) (Oct 1999; Mar 2001, 2002); Daintree River (Blows and Kelemen); Cowbay, Rykers Creek and Emmagen River (Cape Tribulation) (Nov 2000; Mar 2001, 2002; Mitrovski); Mount Cook, Botanical Gardens and Endeavour Falls (Cooktown) (Mar 2001, 2002; Nov 2002; also Sep 2003, Dean); Iron Range NP (Mar 2002).

Distinguishing features. Coarsely setulose primary clasper (surstylus); secondary clasper with only 2 large curved spines, not circular; short submedian spines on caudal margin of novasternum, the latter margin not bicornute and not strongly convex; male abdomen tan, not blackened posteriorly.

Description.

Body length: 1.9 mm.

Head: Arista with 4 branches above and 2–3 below plus a terminal fork. Frontal width and length subequal (fw:fl = 1.0), tapered anteriorly, yellowish tan, orbits slightly darker and subshining. Pedicel and first flagellomere also yellowish tan, face whitish. Head width 2.5 times frontal width. Orbitals in approximate ratio 7:2:7. Eyes with dense, short, pile.

Thorax: Brown. Acrostichal hairs in 6 rows in front of anterior dorsocentral setae, 4 irregular rows between dorsocentrals. Ratio anterior/posterior dorsocentrals 0.6. Sternoindex 0.5. Sex comb of males in two longitudinal and unequal parts ( Fig. 9 ): the larger proximal comb lies along the entire length of the metatarsus and is unevenly curved and the smaller distal comb lies along the second tarsal segment and is smoothly curved. The proximal comb has 12–13 robust loosely-spaced teeth and one or two terminal teeth out of line with the others. The teeth of the basal half of the proximal comb are tightly appressed, as are those of the distal comb.

Wing: Hyaline. C-index, 2.0; 4v-index, 2.8; 4c-index, 1.5; 5x-index, 3.7; M-index, 1.1; ac-index, 2.7; heavy setation occupies half of the third costal section.

Abdomen, male and female. Tergites of males and females yellowish with apical black bands narrowing slightly laterally, terminating prior to the ventral margins.

Terminalia male ( Figs. 7, 10 ): Epandrium (genital arch) is broad above with about 8 setae ( D. serrata 10) along posterior margin, 10–12 setae below, and a small protuberance ( Fig. 8 ) near the surstylar base, visible in both caudal and lateral views. The surstylus (primary clasper) is free with a discrete slightly curved row of about 5–6 short robust prensisetae basally, separated from about 12 much larger prensisetae spaced irregularly over much of the remaining surface, of these latter teeth or pegs, 3 or 4 form a loosely spaced line extending from near the base to the apex inside the row of short robust prensisetae ( Figs. 7, 8 ). With experience the grossly setigerous surstylus is evident in undissected males at 50× magnification, a character useful for separating this species from others in the D. serrata complex. In addition to the peg-like prensisetae, 2 long strong straight setae arise from the surstylus and terminate near the aedeagal apex. The cercus has about 20 setae more-or-less evenly distributed. There are no short robust setae or pegs along the ventral cercal margin, the largest seta is long, not peg-like, and located close to the basoventral corner. The ventral cercal lobe (secondary clasper) is free, almost rectangular not circular or elliptic, with 2 very large curved black medial teeth and about 6 setae along the lateral margin; the 2 very large teeth are well-separated from the latter.

The sides of the hypandrium in ventral view are slightly concave and the parts close to the points of articulation are prominent and angular. The novasternum has two small submedian setae and is without pubescence along the posterior margin. The aedeagus ( Figs. 10–11 ) is hirsute subapically. The dorsal posterior lobe (posterior paramere) is finely serrate with a long smooth finger-like projection ( Fig. 11 ).

Terminalia female ( Figs. 12–13 ): The female egg guides have 16–17 short peg-like teeth.

Etymology. The name given to this species is from the language of the Tjapukai people; the word “ Bunnanda ” is the name of a fabled water fairy that lives in Lake Placid, a reference to the type locality.

Distribution ( Fig. 18 ). Townsville to Heathlands, northeastern Australia.

Drosophila bunnanda occurs from Heathlands (11.8°S) through Iron Range National Park (12.7°S) and at predominantly low altitude locations (except Lake Barrine at 739m) to Townsville (19.4°S). The species was absent in the collections of McEvey (Torres Strait, 1981); Bradfield (Northern Territory, 1980); Schug, Gray Smith & McEvey (Thursday Island, 2003); McEvey (Wanigela, Papua New Guinea, 2003); Moulds & Humphrey (New Ireland, 2001); McEvey ( Christmas Island, 2003), and Barker, Polak, Starmer & McEvey ( New Caledonia, 2000). It appears to be restricted to the Australian mainland, inhabiting tropical rainforest of the northeast coast of Queensland; if its range does extend into New Guinea or surrounding islands then its distribution there may be restricted. Further sampling is required to determine the limit of the northern range of Drosophila bunnanda .

Remarks

Drosophila bunnanda most closely resembles D. serrata in the form of the sex comb, and the oblong shape (not circular or rounded) of the secondary clasper which bears just two large curved spines. The two species may be separated by reference to the degree to which the primary clasper is armed with strong peg-like setae (prensisetae)— D. bunnanda is clearly more spinulose. This character together with a more subtle but consistent difference in the pigmentation of the cercus (entirely pale in D. serrata , noticeably darker edges in D. bunnanda ) is visible, with experience, at low magnification and therefore useful in sorting anaesthetised male specimens.

Microsatellite and mitochondrial DNA markers can reliably differentiate between D. bunnanda , D. birchii and D. serrata of either sex ( Schiffer et al. 2004) and also D. kikkawai and D. sp. cf. jambulina (Schiffer unpublished data).

The forelegs of D. bunnanda (ex LPX) and D. serrata (ex YS) males have been dissected for detailed comparison of sex combs. Males of the D. serrata complex have a sex comb in two longitudinal and unequal parts: the larger proximal comb lies along the entire length of the metatarsus and is unevenly curved; the smaller distal comb lies along the second tarsal segment and is smoothly curved ( Fig. 9 ). The teeth of the proximal comb are not evenly spaced or of equal size—three kinds can be identified: (a) very fine and densely appressed teeth, impossible to count at 120× magnification, (b) robust looselyspaced teeth, readily distinguished (and countable) at 120× and (c) two or three robust teeth set off from the rest terminally. The distal comb comprises additional tightly appressed teeth in a curved row. Drosophila bunnanda has 12–13 loosely-spaced teeth and Yeppoon D. serrata has nine; this differs from Mather’s (1955, p. 565, fig. 9) illustration of the D. serrata sex comb, he shows a proximal comb with 13 teeth, consequently the Yeppoon D. serrata proximal comb is slightly shorter. The appressed teeth enlarge slightly at the basal end of the distal comb in D. serrata but not in D. bunnanda , we have not established the intraspecific variability of this character. We note that the basal teeth of the proximal comb of D. kikkawai are not so tightly appressed and are fewer in number.

Figures

FIGURES 7 – 13. Terminalia and male foreleg of Drosophila bunnanda (ex type strain LPX). (7) epandrium, caudal view; (8) epandrium, lateral view; (9) part of male foreleg showing sex comb; (10) hypandrium, ventral view; (11) hypandrium, lateral view; (12) female ovipositor, lateral view; (13) female ovipositor, ventral view.

FIGURES 14 – 20. Distribution maps of Drosophila montium subgroup species in the Australasian Region. (14) Drosophila dominicana. (15) Drosophila montium subgroup species undissected and unclassified. (16) Drosophila kikkawai. (17) Drosophila sp. cf. jambulina. (18) Drosophila bunnanda (19) Drosophila birchii. (20) Drosophila serrata.