Pleioplectron rodmorrisi, Hegg & Morgan-Richards & Trewick, 2019

Hegg, Danilo, Morgan-Richards, Mary & Trewick, Steven A., 2019, Diversity and distribution of Pleioplectron Hutton cave wētā (Orthoptera: Rhaphidophoridae: Macropathinae), with the synonymy of Weta Chopard and the description of seven new species, European Journal of Taxonomy 577, pp. 1-46 : 38-40

Pleioplectron rodmorrisi sp. nov.

urn:lsid:zoobank.org:act:30DFE3FC-B505-4B33-931E-183676CDF422

Figs 2 A–B, 6F, 7J, 9M–O, 11M–O, 17, 18J

Diagnosis

A medium-sized cave wētā that inhabits rock bluffs in the sub-alpine and low alpine regions of the Kaikōura Ranges and North Canterbury on South Island, New Zealand, up to an elevation of approximately 1500 m a.s.l. A strikingly beautiful and unmistakeable animal, it stands out for its unusually long legs (especially in the males), red-orange legs and antennae, purple-black back and a bold dorsal yellow median line.

Etymology

Named for Rod Morris, biologist and wildlife photographer, who first discovered and documented the species in the Seaward Kaikōura Range in 1993.

Material examined (see also Table 11 in Supplementary Material)

Holotype

NEW ZEALAND • ♂, adult; Kaikōura (KA), Seaward Kaikōura Range, Kahutara Saddle; 42.3229282° S, 173.4276819° E; 1200 m a.s.l.; 1 Apr. 2017; Danilo Hegg leg.; rock bluffs in low alpine zone; night search + insect net; NMNZ AI.037492 (prev. MPN CW3395 ).

Paratype

NEW ZEALAND • ♀, adult; Kaikōura (KA), Inland Kaikōura Range , Hodder River, Hodder Huts; 41.970802° S, 173.63714° E; 1400 m a.s.l.; 4 Apr. 2018; Danilo Hegg leg.; rock bluffs in low alpine zone; night search + insect net; NMNZ AI.037493 (prev. MPN CW3822 ) .

Other material

NEW ZEALAND – Kaikōura (KA) • 1 ♂; Seaward Kaikōura Range, Kahutara Saddle ; 42.32293° S, 173.42768° E; 1200 m a.s.l.; Dec. 1993; R. Morris leg.; rock bluffs in low alpine zone; photograph • 4 ♂♂, 4 ♀♀; Seaward Kaikōura Range, Kahutara Saddle ; 42.32293° S, 173.42768° E; 1200 m a.s.l.; 3 Jan. 2017; D. Hegg leg.; rock bluffs in low alpine zone; night search + insect net; MPN CW3536 to CW3539 , CW3908 , CW3909 , CW4020 , CW4021 • 8 ♂♂, 9 ♀♀; same collection data as for holotype; MPN CW3297 , CW3298 , CW3380 to CW3386 , CW3394 , CW3396 , CW3397 , CW3403 , CW3404 , CW3905 to CW3907 • 1 ♂; Hodder River, Hodder Huts ; 41.970802° S, 173.63714° E; 1400 m a.s.l.; 18 Feb. 2014; B. Taylor-Smith and N. Smith leg.; rock bluffs in low alpine zone; night search; MPN CW2735 • 3 ♂♂, 1 ♀; same collection data as for paratype; MPN CW3821 , CW3823 to CW3825 • 2 ♂♂; Hodder River ; 41.95700° S 173.65023° E; 1150 m a.s.l.; 6 Apr. 2018; D. Hegg leg.; under boulders at bush-line; night search +, insect net; MPN CW3819 , CW3020 . – North Canterbury (NC) • 1 ♂; Organ Range, Mt Skedaddle ; 42.67084° S, 172.52222° E; 1400 m a.s.l.; 16 Feb. 2012; W. Chinn leg.; rock bluffs in low alpine zone; photograph; iNaturalist 9067227 .

Description

MEASUREMENTS. See Table 1.

HEAD. Frons glabrous, pale pink-orange, with dark patches under eyes; vertex glabrous and of variegated colour. Eyes dark brown. Fastigium dark, with a white spot on either side, but yellow anteriorly. Scapes and peduncles orange-red and hairy; antennae orange-red, covered in fine setae. Maxillari and labial palpi pale, with fine tomentum. In sexually mature males some antennal segments may have sensory hair tufts as in P. simplex (see Fig. 5 ).

THORAX. Pronotum pink orange, with a prominent yellow median line, and black regions next to all margins; covered in sparse, fine tomentum. All margins slightly rounded. Anterior corners of pronotum rounded, posterior corners more angular.

LEGS. Very long, sexually dimorphic (see Fig. 17 ), longer in males than in females. Coxae and trochanters pale pink/orange. Fore and mid femora orange. Hind femora variegated, purple in proximal portion and Fore leg: F = 198.5 on 1 and 13 degrees of freedom; P = 3×10 -9; R 2 = 0.9385.

Mid leg: F = 130.9 on 1 and 13 degrees of freedom; P = 4×10 -8; R 2 = 0.9097.

Hind leg: F = 16.18 on 1 and 13 degrees of freedom; P = 0.001; R 2 = 0.5545.

orange in distal part; hind tibiae orange. Fore femora armed below with 3 to 8 needle-like, prolateral linear spines; armed with one prolateral and one retrolateral spine at apex. Fore tibiae generally with three linear spines below on both anterior and posterior edges. Fore tibiae armed with two long spines below (one prolateral and one retrolateral) and two short spines above (one prolateral and one retrolateral) at apex. Mid femora armed below with 1 to 9 prolateral and up to two needle-like, retrolateral linear spines and with one prolateral and one retrolateral spine at apex. Mid tibiae with three linear spines below on both anterior and posterior edges, and up to two linear spines above on posterior edge. Mid tibiae armed with two long spines below (one prolateral and one retrolateral) and two short spines above (one prolateral and one retrolateral) at apex. Hind femora armed below with 9 to 23 prolateral and 6 to 10 retrolateral linear spines. Hind tibiae with 30 to 46 small linear spines above on both anterior and posterior edges. Linear spines on hind tibiae more uniform in size than in other species of Pleioplectron (see Fig. 7J ). Hind tibiae with two superior subapical spines (one prolateral and one retrolateral), two superior apical spines (one prolateral and one retrolateral), two inferior apical spines (one prolateral and one retrolateral) and two inferior subapical spines (one prolateral and one retrolateral). Superior subapical spines about as long as inferior subapical spines and inferior apical spines about 50% longer, but twice as thick at base. Superior apical spines approximately twice as long as inferior apical spines. Hind tarsi with four segments, first and second segment with a pair of spines on distal end. First segment with 6–14 small dorsal, alternate spines. Second segment with 1–6 small dorsal, alternate spines. Second and fourth segments approximately one third of length of first segment, third segment one third of length of second and fourth segments.

ABDOMEN. Tergites pink/purple, black next to anterior and posterior margins; covered in sparse, fine tomentum. Dorsal yellow median line very pronounced and continuous all the way to last tergite.

MALE TERMINALIA. Cerci long, pointed at apex, pale, clothed in setae. Styli short and thin, pale and hairy. A V-shaped structure connected by a membrane protrudes beyond both suranal and subgenital plates, well visible both from above and from below ( Fig. 9 M–N).

FEMALE TERMINALIA. Subgenital plate an inverted V, pointed ( Fig. 11M ). Ovipositor reddish-brown, short (approximately 60% of body length), curved upwards at apex, and terminating in a sharp point. Upper valve smooth above and lower valve with 6 to 8 very strong teeth on ventral edge at apex ( Fig. 11 N–O). Dorsal view of terminalia similar to that in P. simplex ( Fig. 12A ).

Figures

Fig. 2. Phylogenetic relationships of Pleioplectron Hutton, 1896 cave wētā based on mtDNA sequence. A. Bayesian analysis using a mtDNA sequence alignment of 1429 bp spanning the majority of COI, with a minimum individual sequence length of 1330. Posterior probabilities are shown by nodes. B. Maximum Likelihood tree using PhyML with a COI alignment that contained sequences ranging from 483bp to 1429 bp, although the majority were>850 bp at the 3′ end of the gene. C. Map of New Zealand entomological (Crosby) regions. These codes are indicated in the Material examined section for each species.

Fig. 5. Pleioplectron simplex Hutton, 1896, adult ♂, Hinewai Reserve, Banks Peninsula (MPN CW4109). Detail of antenna showing sensory hairs. Scale bar = 1 mm.

Fig. 17. Sexual dimorphism in the legs of Pleioplectron rodmorrisi sp. nov., with boxplot for a sample of 8 adult males and 7 adult females. ‘Leg length’ was calculated as the sum of the lengths of femur and tibia. A–B. Photographs of live specimens of P. rodmorrisi sp. nov. in their natural environment. Kahutara Saddle, Seaward Kaikoura Range. A. Adult ♂. B. Adult ♀. C. Box plot for the ratio of leg length/body length, by sex. A one-way ANOVA test on leg length by sex shows that all legs are significantly longer in males than they are in females, with the following results:

Fig. 7. Left hind tibia of cave wētā in the genus Pleioplectron Hutton, 1896, dorsal view. A. P. simplex Hutton, 1896, adult ♀, Hinewai Reserve, Akaroa (MPN CW4114). B. P. hudsoni Hutton, 1896, adult ♂, Otaki Forks, Tararua Forest (MPN CW3890). C. P. thomsoni (Chopard, 1923) comb. nov., adult ♂, Claremont Bush Reserve, South Canterbury (MPN CW4115). D. P. triquetrum sp. nov., adult ♂, Hinau Track, Kaikōura (MPN CW3921). E. P. auratum sp. nov., adult ♂, Whites Beach, Rarangi (MPN CW4295). F. P. gubernator sp. nov., adult ♂, Lewis Pass (MPN CW4066). G. P. caudatum sp. nov., adult ♂, Moeraki River (MPN CW4239). H. P. flavicorne sp. nov., adult ♀, Brewster Hut Track, Haast Pass (MPN CW3896). I. P. crystallae sp. nov., adult ♂, Cave Brook, Gouland Downs (MPN CW3994). J. P. rodmorrisi sp. nov., adult ♂, Hodder River, Inland Kaikōura Range (MPN CW3819). Scale bar = 5 mm.

Fig. 9. Adult male terminalia of cave wētā in the genus Pleioplectron Hutton, 1896. Left column: ventral view (subgenital plate); central column: dorsal view; right column: lateral view. A–C. P. gubernator sp. nov., Lewis Pass. A. MPN CW4063. B. MPN CW4067 C. MPN CW4059. D–F. P. caudatum sp. nov., Brewster Hut Track, Haast Pass (MPN CW4053). G–I. P. flavicorne sp. nov., Brewster Hut Track, Haast Pass (MPN CW4055). J–L. P. crystallae sp. nov., Cave Brook, Gouland Downs, Heaphy Track. J. MPN CW3994. K–L. MPN CW3995. M–O. P. rodmorrisi sp. nov., Kahutara Saddle, Seaward Kaikōura Range. M. MPN CW3536. N–O. MPN CW3395. Scale bars = 1 mm.

Fig. 11. Adult female terminalia of cave wētā in the genus Pleioplectron Hutton, 1896. Left column: subgenital plate; central and right columns: ovipositor. A–C. P. gubernator sp. nov. A. Awapoto Hut, Abel Tasman NP (MPN CW4057). B–C. Lewis Pass (MPN CW4071). D–F. P. caudatum sp. nov., Brewster Hut Track, Haast Pass (MPN CW4040). G–I. P. flavicorne sp. nov., Brewster Hut Track, Haast Pass (MPN CW4042). J–L. P. crystallae sp. nov., Cave Brook, Gouland Downs, Heaphy Track. J. MPN CW3993. K–L. MPN CW3990. M–O. P. rodmorrisi sp. nov., Hodder River, Inland Kaikōura Range (MPN CW3822). Scale bars = 1 mm.

Fig. 12. Adult female terminalia of cave wētā in the genus Pleioplectron Hutton, 1896, dorsal view (suranal plate). A. P. simplex Hutton, 1896, Hinewai Reserve, Banks Peninsula (MPN CW4114). B. P. crystallae sp. nov., Salisbury Lodge, Mt Arthur (MPN CW3941). C. P. caudatum sp. nov., Brewster Hut Track, Haast Pass (MPN CW4040). Scale bars = 1 mm.