Stephoblemmus humbertiellus Saussure, 1877

Zheng, Yan-Na, Gu, Jun-Jie, He, Zhu-Qing, Huang, Huateng & Ma, Li-Bin, 2023, On a taxonomic feature that has been overestimated in classification practice: an integrative taxonomic revision of Stephoblemmus Saussure, 1877 based on morphology and molecular phylogeny (Orthoptera: Grylloidea; Gryllidae; Gryllinae), Arthropod Systematics & amp; Phylogeny 81, pp. 761-779 : 761

Stephoblemmus humbertiellus Saussure, 1877

Figures 2 , 3 , 5A-D , 6A-F , 9A, C, D, S1-3, S5A, B, E, F

Stephoblemmus humbertiellus Saussure, 1877: 428; Chopard, 1936: 31; Qiao et al., 2020: 482

Loxoblemmus nigriceps Chopard, 1933: 120, synonymized by Qiao et al., 2020: 482

Mitius brevipennis Yuan, Ma & Gu, 2022: 596-600, syn. n.

Chinese name.

战素蟋

Examined materials.

CHINA- Tibet Autonomous Region • 8 ♂, 5 ♀. Motuo County, 29°24.5′N, 95°17.6′W, May 31, 2019, Ma, Libin and Zhang, Tao coll. (SNNU); Yunnan Prov. • 5 ♂, 9 ♀. Mengxiu Township , Ruili County , 24°14.9′N, 97°87.6′W, Jun. 13, 2013, Ma, Libin coll. (SNNU); Yunnan Prov. • 1 ♂. Banlao Township , Cangyuan City, 24°22.5′N, 99°19.1′W, Jun. 7, 2013, Ma, Libin coll. (SNNU); Yunnan Prov. • 1 ♂. Longmen Village , Shangyong Town , Mengla County , 21°40.1′N, 101°64.1′W, May 15, 2013, Ma, Libin coll. (SNNU); Yunnan Prov. • 2 ♂. Nanping, Mengman Town , Mengla County, 21°29.6′N, 101°30.3′W, May 18, 2013, Ma, Libin coll. (SNNU) .

Measurements (mm).

♂ (n = 6): BL 7.84 ± 0.03, HL 1.35 ± 0.32, HW 2.77 ± 0.21, PL 1.96 ± 0.02, PW 2.54 ± 0.65, FWL 4.07 ± 0.78, HTL 4.32; ♀ (n = 6): BL 9.00 ± 0.43, HL 1.48 ± 0.21, HW 2.70 ± 0.08, PL 1.99 ± 0.08, PW 2.77 ± 0.23, FWL 3.19 ± 0.98, HTL 4.81 ± 0.76, OL 5.23 ± 0.43.

Emended diagnosis.

Male: Vertex broad and flattened, slightly inclined. Frons truncated. Tegmina reaching the middle of the fifth abdominal tergum. The apical margin of the epiphallic middle lobe slightly and medially concaved. Ectoparamere stripe-like, distally enlarged, and with apical margins concaved. Female: Similar to male for pronotum and feet features. Frons not produced forwards. Tegmina reaching the middle of the third abdominal tergum. Ovipositor smooth, arrow-like, and as long as the hind femur.

Description.

Male: Eyes ovoid, about 1/4 length of head. Postclypeus shaped like a narrow band; the anteclypeus shaped like a broad shield and twice wider than the postclypeus. Labrum shield-like, apical margin slightly round. Last article of the maxillary palpi slightly longer than the third. The last article of labial palpi depressed and widened, almost equal to the total length of the remainder articles. Tegmina reaching the middle of the fifth abdominal tergum. In tegmina dorsal field, presenting three chord veins, connecting to the proximal of the mirror by two veins; diagonal vein proximally bifurcated, both branches connecting to CuA vein; with two oblique veins; mirror shield-like; dividing vein absent; apical field slightly short, about 1/5 length of the basal field and armed with irregular cells. In the lateral dorsal field, five branches of the subcostal vein. Inner tympanum absent. Hind tibiae armed with dorsal spurs, five inner dorsal spurs, and six outer dorsal spurs; outer apical spurs three (this dorsal apical spur about 3/2 length of the dorsal spurs, ventral and middle ones almost equal in length and about half the length of the dorsal spurs) and inner two (equal in length and slightly longer than the dorsal spurs).

Genitalia.

Epiphallic middle lobe about 1/4 length of the lateral lobe and its apical margin slightly and medially concaved. Epiphallic lateral lobe sheet-like, distally broad, and armed with an apex dorsally protruding (Fig. 6E ). Ectoparamere stripe-like, distally enlarged, and with apical margins concaved.

Female.

Similar to males for pronotum and feet features. Frons not produced forwards. Tegmina reaching the middle of the third abdominal tergum (Fig. 9A ). Ovipositor smooth, arrow-like (Fig. 9C-D ), and as long as the hind femur.

Coloration.

Body dark brown. Tegmina, clypeus, and labrum brown. Ocelli, maxillary palpi, and labial palpi yellowish.

Remarks.

It is the type species of the genus Stephoblemmus . The species is distinguished by its truncated frons of the male (Fig. S5C-D, G-H), and it is very close to M. brevipenis . We examined all the specimens of S. humbertiellus in hand and the holotype of M. brevipenis and found that its genitalia is very similar to those of M. brevipenis , but in the apical margin of the epiphallic middle lobe somewhat different. M. brevipenis apical margin of epiphallic middle lobe slightly concave. However, as there was only one specimen of M. brevipenis , we analyzed their DNA barcode to determine whether the difference in the apical margin of the epiphallic middle lobe was interspecific or intraspecific. And all methods supported M. brevipenis and S. humbertiellus was one MOTU. Thus, M. brevipenis and S. humbertiellus should be one species, and M. brevipenis should be a junior synonym of S. humbertiellus.

Figures

Figure 2. Time-calibrated phylogeny inferred using BEAST. Posterior probability (PP) values are indicated by node color. Node numbers next to nodes represent the divergent times. Purple bars indicate 95 % credibility intervals of estimated node ages. The left in Roman numbers represents fossil calibration points. The primary species of study for this article are shaded red, including species of Loxoblemmus, Mitius, and Stephoblemmus. The blue letter is the type species of Stephoblemmus. The geological timescale is shown at the bottom (Ma = million years ago).

Figure 3. The maximum-likelihood (ML) tree for 30 samples of Mitius and Stephoblemmus using the concatenated COX 1 + 18 S + 28 S data set, and the species delimitation results. Posterior probabilities from MRBAYS (left) and bootstrap supports from IQTREE (right) are indicated for all nodes. Clade nodes are marked in red to indicate the morphology of the male's head.

Figure 5. A - D Males' heads of S. humbertiellus, scale bar: 1 mm. A, B S. brevipenis syn. n.; C, D holotype; E, F males' bodies of S. humbertiellus, scale bar: 5 mm. E S. brevipenis syn. n.; F specimen bearing extremely protruding frons; G male body of Loxoblemmus detectus (Serville, 1838), scale bar: 5 mm.

Figure 6. A - F Genitalia of S. humbertiellus, scale bar: 0.5 mm. A - C S. brevipenis syn. n., D - F holotype, G - I Genitalia of L. detectus. Notes: These two species are distinguished in epiphallic media lobe.

Figure 9. A - B Female body, scale bar: 5 mm; A - S. humbertiellus; B - S. enatus comb. n.; C - F ovipositor, scale bar: 0.5 mm, C - inside of ovipositor of S. humbertiellus; D - outside of ovipositor of S. humbertiellus; E - inside of ovipositor of S. enatus comb. n.; F - outside of ovipositor of S. enatus comb. n.