Laevifacies, Liao, Shuran, Wang, Zongqing & Che, Yanli, 2019

Liao, Shuran, Wang, Zongqing & Che, Yanli, 2019, A new genus and a new species in the subfamily Polyzosteriinae (Blattodea, Blattidae) from China, ZooKeys 852, pp. 85-100 : 88-89

Laevifacies gen. nov.

Type species.

Laevifacies quadrialata sp. nov. here designated.

Generic diagnosis.

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.

Etymology.

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.

Remarks.

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).

Geographical distribution.

China (Hainan).