Minicosta, Brown, Brian V. & Oliver, Hugh, 2008

Brown, Brian V. & Oliver, Hugh, 2008, Two new genera of Phoridae (Diptera) from New Zealand, Zootaxa 1933, pp. 1-11 : 7

Minicosta n. gen.

( Figs. 18–28 )

Diagnosis. Frons lacking medial furrow ( Figs. 24–25 ). Supra-antennal setae absent. Dorsal and ventral fronto-orbital setae absent. Ventral interfrontal setae absent in male, medioclinate and with crossing tips in female. Flagellomere 1 in male greatly elongate, tapered; less so in female. Arista apical, three segmented. Anepisternum without furrows (= undivided), bare ( Figs. 18–19 ). Scutellum with one large and one small seta ( Fig. 21 ). Wing present in both sexes, costa short (about 0.30 wing length), vein R2+3 absent ( Fig. 26 ). Wing vein Rs with one long seta near base only. One alular seta present. Midtibia with one anterodorsal and one dorsal seta near base, with one extremely short anterodorsal seta near apex. Posterior face of hind femur with line of four long ventral setae near base, heavily striate otherwise unmodified ( Figs. 22–23 ). Hind tibia without dorsal, longitudinal setal palisade; with one anterodorsal seta near base.

Recognition. The relationships of Minicosta to other phorid genera are unknown, other than to state that it does not belong in the Metopininae . We have collected sequence data from this genus that will be used in a molecular phylogenetic analysis of the family (B. Brown & P. Smith, in preparation).

In the latest key to males of phorid genera (Disney, 1994), Minicosta keys to couplet 83, where it matches neither lead. We suggest the following modification:

83. Frons with only 6 large setae, with the pre-ocellar (= dorsal interfrontal), postero-lateral, (= inner verti-

cal), and ocellar pairs present. Costa extremely short, 0.30 wing length ................................... Minicosta - Frons with more frontal setae; costa not so reduced in length............................................................83A 83A. Arista dorsal, in preapical position. Subcosta well developed...................................................................

.......................................................................................................................................... Triphleba (part) - Arista apical. Subcosta weakly developed or absent .............................................................. Xanionotum

Females key to couplet 152 in Disney’s (1994) female key, which should be modified as follows to allow recognition of both new genera:

152. With eight bristles on the frons between the two supra-antennals and ocelli (e.g., Disney, 1994, fig. 8.1a). Known from New Zealand ( Kierania ) and the Holarctic Region ( Triphleba )

.......................................................................................................... Kierania (part) and Triphleba (part)

- With six or fewer bristles on the frons between the two supra-antennals (when present) and ocelli, with at least the antero-laterals (= ventral fronto-orbital setae) being absent. Only known from New Zealand...........................................................................................................................................................152A

152A.Costa extremely short, approximately 0.30 wing length ( Fig.26 ). Frons lacking supra-antennal, anterolateral and medio-lateral setae. Antial setae medioclinate, crossing at tips ( Fig. 25 ) ............... Minicosta

- Costa approximately 0.48 wing length or longer. Frons with supra-antennal and medio-lateral setae present. Antial setae reclinate............................................................................................................152B

152B.Costa approximately 0.6 wing length; vein M1 strongly anteriorly curved at base ( Fig. 17 ); proboscis elongate, sclerotized labrum about two times length of palpus ......................................... Bothroprosopa

- Costa approximately 0.48 wing length; vein M1 only gently curved anteriorly ( Fig. 14 ); proboscis short, labrum inconspicuous, subequal in length to palpus ...................................................................... Wharia Derivation of name. From Greek minys for short, referring to the length of the costal vein.

Figures

FIGURE 17. Bothroprosopa mirifica Schmitz, wing.

FIGURES 18 – 23. Minicosta mollyae new species, specimen from Desert Road [LACM ENT 221482]. 18, habitus, left lateral. 19, head and thorax, left lateral. 20, mouthparts, anterior. 21, thorax, dorsal. 22, hind femur, posterior. 23, hind femur, posterior, basal area.

FIGURES 24 – 28. Minicosta mollyae new species. 24, male head, specimen from Desert Road [LACM ENT 221482]. 25, female head, specimen from Raglan [LACM ENT 221394]. 26, wing, specimen from Desert Road at Oturere River [LACM ENT 221484]. 27 – 28. Male terminalia, right lateral and left lateral, specimen (molecular voucher) from Rotopounamu [LACM ENT 235657].

FIGURES 13 – 16. Wharia willcocksorum new species, male. 13, head, specimen from Rotopounamu [LACM ENT 223564]. 14, wing, specimen from Tree Trunk Gorge [LACM ENT 221624]. 15 – 16, male terminalia, right lateral and left lateral, specimen (molecular voucher) from Sandy Bay [LACM ENT 240024].