Timbarragraecia samneilli Rentz, Su and Ueshima 2021, Gen. et sp. nov.

Timbarragraecia samneilli Rentz, Su and Ueshima Gen. et sp. nov.

ANIC number Gen. Nov. 30, sp. 3

(Figs 18A-N; Fig. 20M; Fig. 21C; Fig. 22b G; Table 2, Map 7)

25 https://en.wikipedia.org/wiki/Kokomini

Named in honour of the actor, Sam Neill in recognition for his interest in the indigenous peoples of the region occupied by this species.

Common name. Sam Neill’s Grass Tree Katydid

Holotype male. 1. 15.16S 144.59E 14 km W. by N. of Hope Vale Mission, nr. Cooktown, Qld. 7-10.v.1981 D. C. F. Rentz Stop 34”. 2. D. C. F. Rentz Cytol. prep. 81-155”. 3. Song recorded S-82”. 4. “ ANIC database #14008757”. Holotype in Australian National Insect Collection, Canberra. Paratypes. Queensland. 15.16S 144.59E 14 km W. by N. of Hope Vale Mission, nr. Cooktown, Qld. 7-10.v.1981 (D. C. F. Rentz Stop 34, DCF Rentz, 6 males, Cytol. preps. 81-105, -108, -160; 1 female, ANIC).

Type locality. The type series was found in a clearing amongst a dense stand of Xanthorrhoea johnsonii A. T. Lee APNI to 2.5 m height. The katydids were found much lower on the host plant. The area was a red sand substrate with tall eucalypts, flowering acacias and dense Blady Grass along the dry Cutter’s Creek.

Measurements. Table 2

Differential diagnosis. Body shape robust to slender, size small for genus Fig. 18A, (Table 2). Colour of all specimens uniformly grey brown with a thin faint stripe down the middle of the dorsal surface of the abdomen. Frons similar in colour to the rest of the specimen; some specimens with light greenish blue stripes on frons. Fastigium of vertex short, conical, dorsal surface without a sulcus (Figs 18C, D, E). Antennal scape produced on internal margin, of similar colour to pedicel and flagellum, remainder of body greyish brown; eye brown. Tegmina of males protruding and overlapping and extending to seventh abdominal tergite, tegmina of males with internal margin and lateral margins light yellow brown in life, this fading on pinned specimens. Tenth tergite with prolonged decurved projection, broadly sulcate (Fig. 18I). Male cercus slender (Figs 18J, K) with subapical internal tooth; subgenital plate broad, with broad, shallow median incision, style elongate. Head. Very strongly slanting, produced well in front of pronotum (Fig. 18F); frons smooth shining, genae minutely wrinkled; fastigium of vertex short, without sulcus, touching very weak, shallow frontal fastigium; eye ovoid, moderately bulging; median ocellus very small, lateral ocelli larger, positioned at base of fastigium of vertex (Fig. 18C). Thorax. Pronotum rugulose, with lines and minute tubercles (Fig. 18F); lateral lobe more regularly punctate, ventral margin weakly undulating, not especially modified over thoracic auditory foramen. Thoracic auditory foramen elongate, wholly concealed by pronotum. Prothorax armed with a pair of widely spaced elongate spines; mesothorax with a pair of acute projections posteriorly; metathorax armed on anterior margin with an erect, acute projection on each corner, posterior margin acutely produced apically. Legs. Legs of normal length. Fore coxa with a very elongate tooth. Foreleg with femur armed on anterior margin of ventral surface with 4-5 spines (Fig. 18H), internal margin with a smaller number of smaller spines; tibia unarmed dorsally, ventral surface with 6 spines on both margins. Midleg with femur with 5 substantial spines on anterior margin of ventral surface, posterior margin with 3 smaller spines; tibia unarmed dorsally, ventral surface with 6-7 spines on each margin. Hind leg with femur extending slightly beyond tip of abdomen at rest, ventral surface armed 10 small spines externally, internal margin with 1-3 minute spines near apex (Fig. 18G); tibia with typical number of spines dorsally and ventrally; apex with 2 spurs dorsally, 4 spurs ventrally. Genicular lobes of all femora armed on both sides with a small spine. Tegmina. Male tegmina relatively elongate (Figs. 18A); with costal region well developed, evenly reticulate, costa short, curved, radius and media prominent, parallel for their entire length, extending to apex of tegmen, but slightly dividing subapically and with a few cross veins; mirror elongate with an aching central vein; stridulatory vein faint, file. A bdomen. Male abdomen with tenth tergite produced, decurved, Cercus elongate, with an elongate ventral tooth and a short, quadrate projection dorsally (Fig. 18J, K). Phallic complex with armed massive, produced ventrally, laterally compressed, apex abruptly acute, slightly recurved (Fig. 18L).

Female. Differs from male in following characters: Size larger (Table 2), Female tegmina elongate, strongly divergent, extending to base of 4 th abdominal tergite. not overlapping, costa absent, subcosta and radius parallel for most of their length, feebly divergent apically. ovipositor elongate, very broad (Fig. 18N). Tenth tergite with moderate incision, cercus abruptly narrowing apically; subgenital plate flange-like apically deeply incised (Fig. 18M). Ovipositor (Fig. 18N)

Colouration. Overall colour light greyish brown. Frons not darkened, with some greenish lines (Fig. 18A). Abdomen with faint dorsal median stripe. Legs with some irregular black markings.

Habitat. Found in a clearing with a dense stand of X. johnsoni. After dark the katydids ascended the stalks of the host plant to feed.

Measurements. Table 2

Seasonal occurrence. The record suggests this species occurs in the dry season.

Stridulatory file. The stridulatory file is long and gracefully arching (Fig. 20M) with large lamellar teeth at the proximal end and the broadest in the middle. The teeth gradually taper distally. There are approximately 100 countable teeth in the file.

Song.

Karyotype. 2n male= 31 (30t +Xm) Fig. 22b G Upper karyotype, lower first metaphase.

Recognition. Easily recognised by the colour with a central stripe. Males have a distinctive cercus (Figs 18J, K) and unusual phallic complex (Fig. 18L) with short, sharp titillators with the apices acutely directed outwards.

Comments. This monotypic genus is related to Cooloolagraecia spp. (p. 26) and occurs in similar ecological conditions. It feeds on the same kinds of plants after dark. Its occurrence well to the north of the known range of Cooloolagraecia species suggests that other species in this complex may await discovery in similar habitats.