Two new species of Pseudocoremia and reinstatement of P. pergrata ...

New Zealand Entomologist 26: 61-64 (December 2003)

Two new species of Pseudocoremia and reinstatement of P. pergrata as species (Lepidoptera: Geometridae: Ennominae) Andréa E.A. Stephens1, 2 and George W. Gibbs School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington 1 Author for correspondence. [email protected] 2 Current address: HortResearch, Mt Albert Research Centre, Private Bag 92-169, Auckland

Abstract Two new species of Pseudocoremia (tribe Boarmiini) are described, Pseudocoremia amaculata sp. nov. from St Arnaud, Nelson Lakes National Park, and Pseudocoremia dugdalei sp. nov. from the Waitakere Range, Auckland. It is also determined that P. pergrata, which has been synomynised with P. insignita, should be reassigned species status. Keywords: Pseudocoremia, Ennominae, Geometridae, new species Introduction The genus Pseudocoremia occurs throughout mainland New Zealand and on the Chathams and Norfolk Island. It contains a number of forests moths, including P. suavis, (the common forest looper) which is occasionally epidemic in exotic forest plantations (Scott 1984). Within the group, wing maculation features are notoriously variable to the extent the “the correct determination of species is, in some cases, a matter of considerable difficulty” (Hudson 1928: 137). Dugdale (1988) listed 23 species of Pseudocoremia Butler 1887 and referred to a further two undescribed species held in the New Zealand Arthropod Collection (NZAC). These two species are described and named here. The taxonomy is based on the morphological species concept. The working definition for a geometrid species, that species be recognised based on genitalic differences, is followed here (Scoble et al. 1995). Taxonomy Descriptions Pseudocoremia amaculata sp. nov. Diagnosis. Pseudocoremia amaculata is easily distinguished from other species of Pseudocoremia by its relatively unpatterned forewings coupled with yellow hindwings. In the male genitalia the apical cornuti form a distinctive horizontal row across the apex of the median cornutus.

Type Material. Holotype: Male, New Zealand BR/MB; St Arnaud Village 610m; 16 Jan 1983; J S Dugdale (NZAC). Paratypes: 2 males, same data as holotype (NZAC). Male see Fig. 1. Forewing length 15-16mm. Forewings: relatively uniform medium brown across the entire surface, basal line and the median lines very faint, terminal line very faint zig-zag, below the apex across the terminal line is a darker brown poorly defined smear. Hindwings: completely yellow with no evidence of peppering. Antennae: bipectinate, with the longest pectinations extending to around 1875µm with pectinations becoming shorter towards the tip of the antennae, distal 22% of antennae without pectinations. Female unknown. Male genitalia see Fig. 5. Uncus trifurcate, gnathos not dentate; juxta two low peaks with a line down centre which extends into peaks, base of juxta ‘w’ shaped; valve does not narrow at the tip nor extend beyond cucullus, costa reaches into cucullus; cucullus oval, terminates prior to ampulla; saccular processes smooth with slight curve terminating just prior to ampulla; ampulla dorsal and ventral processes present; aedeagus with a single large slightly curved median cornutus and approximately 30 apical cornuti in a horizontal row across the top of the median cornutus. Etymology. Named for the almost unpatterned nature of the wings, which differentiate it from other species of Pseudocoremia. Remarks. The species is only known with certainty from the type series. A male Pseudocoremia specimen in NZAC, collected at Hapuka Scenic Reserve on the Kaikoura coast (KA), is probably referable to amaculata, but is rather more strongly marked than the type specimens. Pseudocoremia dugdalei sp. nov. Diagnosis. The primary distinguishing feature of P. dugdalei is the broad white band running parallel 61


Figs 1-4. Pseudocoremia spp., adult males. 1, P.amaculata paratype (St Arnaud BR/MB); 2, P.dugdalei paratype (Waitakere Range AK); 3, P .insignita (Titirangi AK, 13 Apr 1957, C.R.Thomas); 4, P. pergrata (White Pine Bush HB, 27 Dec 1970, T.H. & J.M. Davies).

to the termen of the wing. There is a second narrower white line running parallel to this. The rest of the wing is a mottled yellow-brown. Aedeagus with the median cornutus reduced to a sclerotised area and the central peak of the uncus is rounded rather than pointed. Type Material. Holotype: Male, New Zealand AK; Fletcher Track; Waitakere Ra.; 26 Jan 1980; J S Dugdale (NZAC). Paratype: 1 male, same data as holotype (NZAC). Male see Fig. 2. Forewing length 15-16mm. Forewings: predominately brown and white; basal line white, curved outwards, distinctly broader toward the costa than towards the dorsum; wing is brown between the basal line and the base; area between the faint white median line and the basal line is brown; between the median line and the terminal line is a broad white, almost straight band; terminal line white and zig zag; between terminal line and outer edge of the wing is speckled brown. Hindwings: yellow with grey speckling near base and along dorsum. Antennae: bipectinate, longest pectinations around 1375µm with pectinations 62

becoming shorter towards the tip of the antennae, distal 35% of antennae without pectinations. Female unknown. Male genitalia see Fig. 6. Uncus trifurcate with well-rounded median tine, gnathos dentate; juxta with two peaks with a line down the centre, base of juxta ‘w’ shaped; valve not narrowed at tip nor extending beyond cucullus; costa reaches into cucullus; cucullus oval, terminates prior to ampulla; ampulla both dorsal and ventral processes present but weak and short; saccular processes smooth and straight extending beyond the ampulla; aedeagus with median cornutus reduced to a sclerotised area and no apical cornuti. Etymology. Named in honour of John Dugdale who collected the original specimens of this species and P. amaculata and for his outstanding contributions to New Zealand entomology. Remarks. P. dugdalei is one of only three or four moth species apparently endemic to the Auckland region. It is only known from the two specimens of the type series.

Stephens & Gibbs: New Pseudocoremia species

Fig. 5. P. amaculata male genitalia (top) and aedeagus (bottom). Scale bar = 500µm.

Fig. 6. P. dugdalei male genitalia (top) and aedeagus (bottom). Scale bar = 500µm.

Table 1: Differences between P. insignita and P. pergrata. P. insignita

P. pergrata

Forewings

Variegated Subbasal line curved Subbasal line rather indistinct Median area mid-brown, mottled paler Yellowish

More uniform Subbasal line straight Subbasal line clear white Median area unicolorous chocolate brown Brown and white

Hindwings

Discal spot present, more or less distinct Dark postmedian line more or less well indicated

Discal spot absent or very indistinct No postmedian line

Male genitalia

Sclerotised line down centre juxta present Cucullus oval

Sclerotised line down centre juxta absent Cucullus round

Female genitalia

Ductus bursae long

Ductus bursae short

63


Reinstatement of Pseudocoremia pergrata Dugdale (1988) synonymised the species P. pergrata Philpott 1930 with P. insignita Philpott 1930 (see Figs 3 and 4). However, when viewed within the perspective of a phylogenetic analysis of all species in the genus, as was done by one of us (Stephens 2001), the variation between these two taxa is consistent with the variation seen between other sister species (for example, P. berylia and P. terrena). We believe the synonymy is not justifiable under the morphological species concept, thus it is proposed that the species status of P. pergrata should be reinstated. The major factor separating the two species noted by Philpott (1930) is the structure of the antennae. It appears that Philpott (1930) had relatively few specimens to examine and only looked at males. However, he was able to note a number of differences in the wing pattern. Both species feed on nettles (Urtica spp.) (B. Patrick, unpubl. data) and matagouri (Discaria toumatou) (Spiller & Wise 1982). P. pergrata is known from the eastern South Island (KA, MC, DN) and two localities in the Hawkes Bay district of the North Island (HB); P. insignita is widespread in both the North and South Islands (AK to SL). There are a number of characters that can be used to separate the two taxa. These are summarised in Table 1. Otago Museum specimens of female P. pergrata show a tendency towards brachyptery. Many of the specimens have smaller wings with a sharp point at the apex. This sharp apical point seems to be a polymorphism, and North Island females do not show this character. The sole female of P. insignita examined is the same size as the males, and lacks the apically pointed wing. Acknowledgements We would like to thank the curators of the museums visited, in particular Brian Patrick of Otago Museum, Robert Hoare of NZAC, Manaaki Whenua – Landcare Research NZ Ltd and Phil Sirvid and Ricardo Palma of Te Papa Tongarewa Museum of New Zealand. Robert Hoare also assisted greatly with the figures and made many helpful comments and suggestions on the manuscript. Birgit Rhode (NZAC, Manaaki Whenua – Landcare Research Ltd) took the photos of the whole insects. And thank you to the two 64

referees for numerous helpful comments on the manuscript. References Crosby TK, Dugdale JS, Watt JC. 1998. Area codes for recording specimen localities in the New Zealand subregion. New Zealand Journal of Zoology 25: 175-183. Dugdale JS. 1988. Lepidoptera: annotated catalogue and key to family group taxa. Fauna of New Zealand 14. 262 pp. Hudson GV. 1928. The butterflies and moths of New Zealand. Ferguson and Osborn Ltd, Wellington. 386 pp. 52 pl. Philpott A. 1930. New species of Lepidoptera in the collection of the Auckland Museum. Records of the Auckland Institute and Museum 1: 1–16. Scoble M, Gaston K, Crook A. 1995. Using taxonomic data to estimate species richness in Geometridae. Journal of the Lepidopterists’ Society 49: 136–147. Scott RR. (ed) 1984. New Zealand pest and beneficial insects. Lincoln College, Canterbury. 373pp. Spiller D, Wise K. 1982. A catalogue (1860–1960) of New Zealand insects and their host plants. DSIR Bulletin 231. Stephens AEA. 2001. Pseudocoremia (Lepidoptera: Geometridae: Ennominae): Systematics, biogeography and host plant associations. Unpublished MSc (Hons) thesis, Victoria University of Wellington, New Zealand.