Laevifacies quadrialata sp. nov. here designated.

Body small to medium, thinner in male, thorax slightly broader than abdomen. Surface smooth and shining. Pronotum slightly semicircular, vertex barely exposed. Male with vestigial tegmina and hind wings on mesonotum and metanotum respectively, both nearly triangular; female only with vestigial tegmina, its shape similar to that of male, without hind wings. Legs strong but short, coxae with punctation, front femora Type A₂. Mid and hind metatarsus with strong spines, claws symmetrical. Cerci strong, short and symmetrical. Styli long and symmetrical. Supra-anal plate in male short, triangular; subgenital plate broad and short, slightly quadrilateral and symmetrical. L1 divided into two parts, L3 bifurcated, one branch short, the other one long, R1 nearly claw-like and R2 large, hooked.

The name Laevifacies is derived from two Latin words laevis and facies, referring to the smooth and shining surface of terga. The gender of Laevifacies is feminine.

Based on former studies (Gutiérrez 2013, 2014; Mackerras 1965a, 1965b, 1965c, 1966a, 1966b, 1967a, 1967b, 1968a, 1968b; Rehn and Hebard 1927), the Polyzosteriinae is characterized as follows: species having semicircular pronotum, lobiform vestigial tegmina, angles of T2–T7 produced, tarsi usually short, bare or with hind and sometimes mid metatarsi spiny (Laevifacies with mid and hind metatarsi spiny, while in Mackerras (1968b), Australian species of Blattinae and Polyzosteriinae from other Blattidae with all metatarsi spiny), large pulvilli and arolia, cerci strong, short and symmetrical, L1 with hollow finger-like projection and sclerotized projection and R1 claw-like and margin with projection; thus, Laevifacies is placed in the subfamily Polyzosteriinae. Laevifacies has common features with Melanozosteria, Eurycotis, Leptozosteria, and Platyzosteria, such as body small to large, and shining, usually with vestigial tegmina, angles of T5–T6 acute, T6–T7 with punctation and hind metatarsus usually spiny (Gutiérrez 2013, 2014; Mackerras 1965c, 1968b). Laevifacies is similar to the Melanozosteria and Eurycotis in general appearance, but it can be distinguished from Melanozosteria by the following characters: 1) body thin and small in male (Figure 2A, B), while in Melanozosteria, it is broad and large (Figure 4A, B, F, G); 2) the surface of terga smooth (Figure 2A), vs. surface with punctation in Melanozosteria (Figure 4A, F); 3) male with vestigial tegmina and hind wings (Figure 2A), but in Melanozosteria only with vestigial tegmina or apterous (Figure 4A, F); 4) the margin of L2d smooth and posterior of L2d finger-like with more small spines (Figure 3A), while in Melanozosteria the margin strongly denticulate and posterior of L2d with acute angle (Figure 4J, M); 5) L3 bifurcated, one short and the other long (Figure 3A), however, L3 unbifurcated or bifurcated with branches of equal length in Melanozosteria (Figure 4J, M); 6) R1 fist-shaped (Figure 3C), while in Melanozosteria foot-shaped or finger-shaped (Figure 4K, M); and 7) R2 only with one large and long uniform structure (Figure 3C), while in Melanozosteria, two unequal forked structures present (Figure 4K, M); and it can be distinguished from Eurycotis by the following characters: 1) tibiae not specialized, while in Eurycotis, one group of which species have smooth surface, uniform black body and lateral tegmina, with highly specialized caudal tibiae; 2) R2 is hook-like, while in Eurycotis R2 is pincer-like. In addition, Eurycotis is restricted to South and North America and Cuba, while Laevifacies gen. nov. is found in East Asia. Laevifacies is similar to the Methana in the following genitalia characteristics, the margin of L2d smooth, R1 as a strongly claw-like sclerotized process, both of L1 have two structures, L1 of Methana has strong finger-like sclerotization and a membranous lobe, while Laevifacies has a finger-like membrane and a strongly sclerotized lobe (Figure 3A, B).

Figure 2. 

A–K Laevifacies quadrialata sp. nov. A–F, I–K male holotype A in dorsal view B in ventral view C pronotum, in dorsal view D head, in ventral view E femur, in ventral view F tibia, in ventral view I fore tarsus, in ventral view J mid tarsus, in ventral view K hind tarsus, in ventral view. G–H female paratype G in dorsal view H in ventral view. Scale bars: 5 mm (A–B, G–H); 1 mm (C–F, I–K).

Figure 3. 

A–G male genitalia features from holotype A left phallomere, in dorsal view B L1 of left phallomere, in dorsal view C right phallomere, in dorsal view D subgenital plate, in ventral view E supra-anal plate, in dorsal view F–G female genitalia features from paratype F subgenital plate, in ventral view G supra-anal plate and genitalia, in dorsal view. Abbreviations: a.a., anterior arch; acc.pr., accessory process; bsv., basivalvula; c.a., central apodeme; i.p.p., inner posterior process; lat.st.IX–X, laterosternal of the ninth-tenth segment; L.ph., left phallomere; L1–L3, parts of left phallomere; o.p.p., outer posterior process; R.ph., right phallomere; R1–R3, parts of right phallomere; v.I–III, first-third valve; v.ph., ventral phallomere. Scale bars: 1 mm (A, C–G); 0.5 mm (B).

Figure 4. 

A–E, I–L Melanozosteria nitida from Guangxi, male A in dorsal view B in ventral view C pronotum, in dorsal view D head, in ventral view E tarsus, in ventral view F–H Lectotype of Melanozosteria nitida, male F in dorsal view G in ventral view H labels I subgenital plate, in ventral view J left phallomere, in dorsal view K right phallomere, in dorsal view L supra-anal plate, in dorsal view M genitalia of Melanozosteria nitida in Mackerras (1968a) F–H provided by H. Bruckner, Natural History Museum Vienna, NOaS Image Collection. Scale bars: 10 mm (A–B, F–G); 1 mm (C–E, I–M).

China (Hainan).

Sexual dimorphism. Body small and black. Surface smooth and shining except last two terga with punctation. Tegmina and hind wings vestigial in male, tegmina vestigial and hind wings absent in female. Angles of T2–T7 sharp and protruded. Legs strong. Supra-anal plate short and triangular. Styli long and symmetrical.

Measurements. Male, pronotum: length × width 5.5–6.2 × 7.9–8.0 mm, overall length: 15.6–17.7 mm. Female, pronotum: length × width 7.0–7.1 × 10.5–10.7 mm, overall length: 17.0–21.0 mm.

Body black, smooth, shining. Vertex and frons black. Clypeus to part of labrum brown to dark brown, maxillary palpi and labial palpi dark brown to black. Eyes black when the specimens are fresh, fading after a long time (Figure 2D). Antennae dark brown with near middle segments and tip segments milky white (Figure 2A, B). Pronotum black, surface smooth and shining (Figure 2C). Tegmina and hind wings black, terga smooth except last two terga with punctation (Figure 2A, G). Sterna and legs dark brown to black. Cerci dark brown to black, apex yellowish brown (Figure 2A, B, G, H).

Size small to medium, female larger than male. Body oval, vertex nearly unexposed (Figure 2A, B, G, H). Ocelli present, small and round (Figure 2D). Pronotum nearly semicircular, anterior margin arc-shaped, posterior margin nearly straight, posterior angles blunt (Figure 2C). Small, vestigial tegmina and hind wings present in male, both extending to notal hind margin, only vestigial tegmina in female (Figure 2A, G); angles of T2–T7 sharp and protruded, sterna smooth and shining (Figure 2A, B, G, H). Legs strong, fore coxae with punctation; front femora Type A₂ (Figure 2E); mid and hind metatarsus with a row of spines; hind metatarsus fairly long with pulvillus which occupies nearly one-quarter of its length, remainder of surface with hair, claws moderately symmetrical and unspecialized (Figure 2E, F, I, K). Male: supra-anal plate short, triangular, divided into two round lobes (Figure 3E); subgenital plate broad and short, posterior margin round; styli long and symmetrical (Figure 3D). Cerci symmetrical and strong, with indistinct segmentation, ends sharp (Figure 3E). Female: supra-anal plate with higher sclerotization (Figure 3G).

Left phallomere consisting of three parts: L1, L2, and L3. L1 with two parts L1a and L1b, L1a with membranous finger-like projection; L1b with sclerotized projection. L2 consisting of L2d and L2v, L2d strongly sclerotized in anterior part, the posterior part with finger-like and with more small spines; L2va simple and broad, L2vb sclerotized and the posterior with a spinous projection. L3 with a simple hook, elongate to the right and bifurcated (Figure 3A, B). Right phallomere consisting of R1, R2, and R3. R1 large, claw-like, right margin with a prominent spine; R2 large, curved hook-like, the base strong and gradually becoming thinner, bent to the right; R3 large and cucullate, highly sclerotized (Figure 3C).

The first valve (v.I) long, slightly broad and crescent-shaped, terminal membranous; the second valve (v.II) small, flaky and obscured by the v.I; the third valve (v.III) broader than v.I, terminal membranous; paraprocts (pp.) symmetrical and the middle concave; the middle of anterior arch (a.a.) concave; basivalvula (bsv.) trapezoidal (Figure 3G); inner posterior process of the laterosternal shelf (i.p.p.) divided in two parts, which are connected by hairy membrane; outer posterior process of the laterosternal shelf (o.p.p.) symmetrical, terminal with hairs (Figure 3F).

HOLOTYPE: male, CHINA, Hainan Prov., Baisha, Yinggeling Nature Reserve, 20-VIII-2010, Guo Zheng leg. PARATYPES: 1 male, same data as holotype; 1 male, Hainan Prov., Mt. Wuzhishan, 18-21-V-2014, Shunhua Gui, Xinran Li & Jianyue Qiu leg.; 1 male, Hainan Prov., Diaoluoshan, 18-IV-2015, Lu Qiu & Qikun Bai leg. (GenBank accession number: MK798103); 2 females, Hainan Prov., Lingshui, Mt. Diaoluoshan, 22-V-2014, Jianyue Qiu, Xinran Li & Shunhua Gui leg. (GenBank accession number: MK798104).

The species epithet comes from the Latin word quadrialata in reference to the male having four triangular vestigial wings.

In our study the interspecific K2P genetic divergence among L. quadrialata sp. nov. and other cockroach species ranged from 10.4 to 13.1%. But the genetic divergence value between male and female of L. quadrialata sp. nov. is only 0.9%, so we pair them based on their similar morphology combined with this COI data. Sexual dimorphism occurs in L. quadrialata sp. nov.: 1) females without hind wings, but males with vestigial hind wings (Figure 2A, 2G); 2) male with narrower body, while female with broader body (Figure 2A, B, G, H).

China (Hainan)

Body broad oval and reddish brown to black. Pronotum slightly arched, surface with punctation. Vestigial tegmina sectorial with punctation, separated from mesonotum for nearly whole length, hind wings absent. Surface with punctation. Angles of T2–T7 protruded and sharp. The medial aspects to the styli with stubby and sharp spines.

Male, pronotum: length × width 7.4 × 12.5 mm, overall length: 26.1 mm.

Body uniformly deep reddish brown to black (Figure 4A, B, F, G). Eyes and ocelli yellowish white. Margin of clypeus and labrum dark brown. Vertex and frons black. Antennae brown or black, middle joints creamy-white (Figure 4D). Pronotum, tegmina, abdomen, legs and cerci all uniformly deep reddish brown to black (Figure 4C).

Body large, broad oval and convex, surface shining. Pronotum slightly arched, surface with punctation. Anterior margin of pronotum roundly protruded, and posterior margin straight (Figure 4C). Tegmina vestigial, sectorial, and separated from mesonotum, surface with punctation. Angles of metanotum protruded. Hind wings absent. Surface of all terga shining and with punctation; angles of T2–T7 protruded and sharp, T9 not protruded (Figure 4A, F). Legs short and thick. Fore coxae with slightly punctation; front femora Type A₂ (anterior with two long spines, posterior with many small and slightly equal spines). Tibiae hair-brushes; hind tibiae with a row of spines, hind metatarsus with pulvillus occupying one-quarter to one-third of its length, remainder of ventral surface with spines (Figure 4E). All pulvilli large, claws symmetrical (Figure 4E). Supra-anal plate long, symmetrical and quadrilateral, side edge at gradient, angles of posterior round, the middle of posterior margin concave and with hair. Cerci thick, with blurry segmentation and the terminal segment spinous distally (Figure 4F, G, L). Subgenital plate nearly quadrilateral, short. The medial aspects to the styli with stubby and sharp spines (Figure 4I).

Left phallomere includes L1, L2, and L3. L1 with three parts (a, b, c). L1a slightly sclerotized, posterior not sclerotized, membranous and blunt. L1b more sclerotized and posterior sharp. L1c anterior slightly sclerotized and posterior blunt membrane. L2 includes L2d and L2v. L2d with a well-sclerotized, strongly denticulate in anterior margin, while the posterior of the sclerite becomes more delicate and ends in a sharp point; L2v usually single, L3 is a simple hook, but the posterior divides into two small forks which resemble an elephant’s nose (Figure 4J, 4M). Right phallomere includes R1, R2, and R3. R1 large, elongate, foot-like with broad down-turned “thumb” and 5–6 strongly denticulate on medial edge, R2a long, fairly broad, tapering slightly towards medial corner; R2b shorter, more strongly sclerotized and tapering to long narrow elongation. R3 with structure of folded sclerite (Figure 4K, 4M).

1 male, CHINA, Guangxi Prov., Shangsi, Nadang, 15-XI-1958, Dexiang Gu & Jinting Liang leg.

Lectotype of Polyzosteria nitida, male, Ternate (Natural History Museum Vienna), “Ternate Jeynalle CoII. Br. V. W.”, “LECTOTYPE”, “LECTOTYPE of Polyzosteria nitida Brunn. Selected by KHL Key, 1963.”; holotype of Periplaneta polita, male, Taiwan (Natural History Museum), “Holotype”, “Periplaneta polita Walker”, “BMNH (E) #878036”, presented by Beccaloni (2014).

We compared the lectotype of M. nitida (from Ternate, Indonesia) with the specimen from Guangxi and found there are minor differences between them: the styli are straight in the Guangxi individual (Figure 4I), but in the lectotype of M. nitida, slightly bent (Figure 4F, G). We also compared the genitalia between the Guangxi individual and the illustration in Mackerras (1968a); they share the typical characters of L1b spinous projection and serration along the margin of L2d, but they are also different in the following characteristics: 1) the terminal of L3 divided into two small forks, which resemble an elephant’s nose in the Guangxi individual (Figure 4J), while in the Mackerras (1968a) individual, L3 has one blunt hook (Figure 4M); 2) L2v broad and sclerotized, and posterior of L3 membranous in the Guangxi individual (Figure 4J), while L2v thin, long and with sharp sclerotized terminus in the Mackerras (1968a) individual (Figure 4M). And the variation of supra-anal plate between samples from Queensland and New Guinea were treated as intraspecific differences in different locations (Mackerras 1968a). Considering Mackerras (1968a) also recorded that the M. nitida is a widely distributed tropical species from Taiwan, Malaya, Moluccas, and Philippines, and due to our specimens being inadequate, the minor difference in the Guangxi individual and the lectotype of M. nitida are temporarily considered as the intraspecific differences of different populations.

Australia, Philippines, Malaysia, New Guinea, New Caledonia, New Zealand, China, Thailand.