Peracca macritchiensis Tan & Ingrisch

Tan, Ming Kai & Ingrisch, Sigfrid, 2014, New taxa and notes of some described species of Agraeciini (Orthoptera: Tettigoniidae: Conocephalinae) from Malay Peninsula, Zootaxa 3765 (6), pp. 541-556 : 553-556

Peracca macritchiensis Tan & Ingrisch , new species

Fig. 7

Peracca subulicerca Karny, 1926 — Leong, 2011: 85 –90; Tan, 2012: 44, 46 (images); Tan et al., 2013: 99

Material examined. Holotype (male): Singapore, Bukit Timah Nature Reserve, forest, coll. T. M. Leong, 5 June 2010 ( ZRC).

Paratypes: 4 males, 7 females. Singapore, same locality as holotype: 1 female, coll. T. M. Leong, 23 May 2009; 2 male, 1 female, coll. T. M. Leong, 14 March 2010; 1 male, 1 female, coll. T. M. Leong, 18 March 2010; 2 females, coll. T. M. Leong, 10 April 2010 (all ZRC); 1 female Bukit Timah, coll. P. Grootaert (Station 25330), 7 September 2005, (Brussels ( ISNB)). Singapore, Central Catchment Nature Reserve: MacRitchie forest, 1 female, coll. T. M. Leong 19 December 2009; along Lornie Trail, old secondary forest, 1 male, coll. M. K. Tan & M. R. B. Ismail, 15 November 2010 (all ZRC).

Diagnosis. Male similar to Peracca subulicerca Karny, 1926 but differs by the male tenth abdominal tergite being broadly rounded apically (instead of bulging), very faintly concave but not bilobate in middle; male cerci more bulbous basally; baso-internal process of male cerci not sinuate, bent anteriorly near middle; apex of male cerci with two rounded lobes with minute denticules (instead of short-triangular lobes). The female subgenital plate is unique within the genus in that the apical margin is upcurved in a 180° angle thus that the tip points craniad. The ventral view looks similar to the subgenital plate of P. doriae ( Griffini, 1908) in apical view, in which only the apex is upcurved in an about 90° angle. In the new species, the dorsal side of the plate (what should have been the ventral surface is completely connected to the body by the intersegmental membrane, while in P. doriae the ventral surface is free; thus what forms the ventral surface in the new species might have be developed from a broadened apical margin.

Description. Habitus of male as shown in Fig. 7 A. Fastigium verticis barely surpassing apex of scapus; dorsally with apex acute. Frons shining with impressed dots. Pronotum subrugose, disc broadly rounded into paranota. Tegmen in male micropterous, reduced to stridulatory apparatus, not covered by pronotum ( Fig. 7 B); female squamipterous ( Fig. 7 C). Prosternal spines present. Femora with the following number of spines on ventral margins: profemur 3-4 large and 3-4 small external, 4 large and 6-8 small internal; mesofemur 1 basal, 4 large, 4-7 small external, 1 basal, 0-1 small internal; postfemur 11-13 external, 15 internal (n = 1, holotype). Knee lobes of pro- and mesofemur obtuse externally and spinose internally; of postfemur spinose on both sides, longer than those of pro- and mesofemur (particularly the external).

Male. Tenth abdominal tergite broadly rounded apically, very weakly bilobate in middle ( Fig. 7 D). Cerci bulbous basally; with a large, slightly compressed, baso-internal process, bent anteriorly near middle of process, apex acute; remainder of cercus slightly compressed, long and narrow, gently sinuate; dorsal margin in apical area with minute denticles, very apex split into two rounded lobes, and provided with a long, narrow, curved, acute apical spine ( Fig. 7 E). Subgenital plate with apical margin subtruncate, slightly concave in middle ( Fig. 7 F).

Females (n = 7) - - 7.2–8.6 - 1.0–1.7 17.5–20.5 18.5–21.2 14.8–16.6

(8.0) (1.4) (19.0) (20.3) (15.7)

* abdomen shrunk during dry-preservation. ** body dismembered.

Female. Tenth abdominal tergite with apex deeply and broadly triangularly incised. Cerci with apex pointing. Subgenital plate wider than long, furrowed in middle; apex bilobate and apical margin upcurved ( Figs. 7 G, 7H). Ovipositor dagger shaped; with substraight basal and gently curved apical area; apical area with dorsal margin straight, ventral margin gently curved; margins smooth ( Fig. 7 I).

Colouration. Generally brown to testaceous. Frons, mandibles, labrum, dorsal part of clypeus, genae black; ventral part of clypeus and palpi white; palpi pale yellow with some tint of green; labrum, scapus, pedicellus, vertex and occiput yellow brown; vertex and occiput with some red venation. Pronotum red brown, sometimes with some tint of black and white; in some specimens, disc white (on the outside) and black (on the inside) longitudinal stripe on each lateral side; white spot on anterior and posterior part of that strip; ventral margin of paranota white. Abdomen testaceous to brown with light dots; tergites with faint red brown longitudinal medial strip, with black spot at the posterior margin of each tergite; pleurite with dark red brown marmoration; sternites pale. Legs generally yellow brown, spines white with black apices. Protibia, and to a smaller extend mesotibia, with black spots dorsally, sometimes faint. Postfemur brown with black stripes on interior and exterior surfaces; with apical half black ventrally. Posttibia brown dorsally and black ventrally

Measurements (5 males, 7 females). See Table 4 .

Etymology. This species is named after one of the localities where the species is found: MacRitchie forest in Central Catchment Nature Reserve, Singapore. It is also named to highlight the potential environmental damage befalling the forest reserve due to the proposed construction of the Cross Island Mass Rapid Transport ( MRT) Line.

Figures

FIGURE 7. Peracca macritchiensis sp. n.: male habitus under in-situ conditions (A); tegmina of male (B) and female (C); male abdominal apex in dorsal (D), lateral (E) and ventral (F) views; female abdominal apex in ventral (G) and lateral (H, I) views. Scale bars: 1 mm (B – H); 5 mm (I). Images by Chris Ang (A), MKT (B, D – F, I) and SI (C, G, H).

Tables

TABLE 4. Measurements Peracca macritchiensis sp. n. (in mm, mean values in brackets).

	BL	BWL	PL	PW	TL	HFL	HTL	OL
Male holotype	33.0	-	8.9	6.0	1.9	17.7	18.6	-
Male paratype (14 Mar.2010)	24.7*	-	8.2	6.0	2.0	17.0	17.5	-
Male paratype (14 Mar.2010)	29.1*	-	8.8	6.5	1.8	19.4	20.0	-
Male paratype (18 Mar.2010)	26.9*	-	8.4	6.3	1.9	17.7	18.6	-
Male paratype (15 Nov.2010)	30.9	-	8.6	6.2	2.2	18.3	19.7	-