Scelimena pyrroma Lao, Kasalo, Gao, Skejo et Deng, 2022

Lao, Chuangyu, Kasalo, Niko, Gao, Fan, Deng, Weian & Skejo, Josip, 2022, Review of the Chinese species of the genus Scelimena Serville, 1838 (Tetrigidae Scelimeninae: Scelimenini), Zootaxa 5200 (4), pp. 321-343 : 336-339

5. Scelimena pyrroma Lao, Kasalo, Gao, Skejo et Deng , sp. nov. ( Figs. 1 , 10 , 11 )

Scelimena dentiumeris (partim): Liang & Zheng, 1998: 53–55, Figs. 34a, 34b.

Proposed English and Mandarin vernacular name. Hainan Amberblade Rowerhopper, because it hails from Hainan, because it has amber-yellowish shoulders (the scapula is known as a shoulder blade), and because it is a member of the genus Scelimena , known as Rowerhoppers, due to the paddle-like hind legs. For the Mandarin name, we propose ṘṖĤẦȐ (Ṙ = pale yellow; Ṗ = shoulder; ĤẦȐ = Scelimena ) ， pronounced “ Xiâng jiân cìyìzhà”.

Type material.

Holotype ♀ (specimen code Or-011193 ) ( Figs. 10 , 11 ) PR CHINA: South China: Hainan: central Hainan: Ding'an District (“Ting-an Dist.” on the label): "Tai-tsing-lam-ts'uen, back of Loi-mo-ling Mt. Range " 19.–20.VI.1935. leg. F. K. To (Biology Museum of Sun Yat-sen University, Guangzhou, PR China) ; Paratype 1♂ (specimen code Or-011211) PR CHINA: South China: Hainan: central Hainan: Ding'an District (“Ting-an Dist.” on the label): "Taitsing-lam-ts'uen, back of Loi-mo-ling Mt. Range" 12.–15.VI.1935. leg. F. K. To (Biology Museum of Sun Yat-sen University, Guangzhou, PR China) ( Figs. 10 ).

Additional material. 1 female, photographed alive ( Fig. 1 ), left hind leg missing, PR China: Hainan: Wuzhishan National Nature Reserve Mts. (18.900392N, 109.691035E) ( Fig. 2 ) Photo. Fan Gao 23.I.2022. (https://www. inaturalist.org/observations/112480618).

Type locality. The People’s Republic of China, south China, Hainan Isl., central Hainan, mountains of the Ding’an District (Tai-tsing-lam-ts'uen, back of Loi-mo-ling/Leimoling Mt. Range).

Etymology. Latinized adjective, female gender, first declension, coined of two greek words, one for yellow (πυρρός, pyrros), and the one for the shoulders (ὦμος, omos), pointing to the yellow metalateral projections (ML) or humeral angles.

Justification of the generic assignment with a species group assignment. Scelimena pyrroma is clearly a member of the genus Scelimena , based on the following set of the characters typical for Scelimena members: (1) low position of the frontal costa bifurcation, (2) low position of the lateral ocelli, (3) strong second frontolateral projections (FL2), (4) strongly paddle-like widened distal part of the hind tibia, and (5) strongly widened hind proximal tarsal segment. The species is herewith tentatively assigned to Scelimena producta species group, based on the similarity with endemic to Borneo S. dentiumeris ( Hancock, 1907) and endemic to Vietnam S. chinensis ( Hancock, 1915) . Members of Scelimena producta species group have, unlike members of Scelimena bellula species group, prominent metalateral projections and weakly toothed ventral margins of the hind femora.

Diagnosis. Vertex as wide as a compound eye. Pronotum with only a few recognizable projections (FL2, ML1, ML2, VL). The frontal margin of pronotum with pointed pale-coloured second frontolateral projections (FL2). External lateral carina of the pronotum with medium-sized yellow ML on the humeral angle (and sometimes with one smaller ML2 behind it). Lateral angles or the ventrolateral projections of the paranota (VL) projected outwards and with long spikes directed forwards. This new species is similar to S. dentiumeris ( Hancock, 1907) ( Fig. 12 ) and is probably closely related to this species, but the two can easily be separated following this set of traits: (I) Shoulders are more angulated in S. pyrroma sp. nov., i.e., more rounded in S. dentiumeris . (II) Pronotal discus strongly undulated in S. pyrroma sp. nov., and almost flat in S. dentiumeris . (III) In S. pyrroma sp. nov. median carina of the pronotum lightly depressed before the promedial elevation of the median carina, while in S. dentiumeris the median carina is straight in that part. (IV) Metamedial projections of the pronotum in S. pyrroma sp. nov. subtriangular and clearly visible in lateral view, while in S. dentiumeris they are suboval and only barely visible in lateral view. (V) Dorsal anterior part of mid femora in S. pyrroma sp. nov. bear a distinct tubercle, while in S. dentiumeris the dorsal margins of mid femora are straight. (VI) Hind femora stouter in S. pyrroma (3.8-4.0 times as long as wide) than in S. dentiumeris (more than 4.2 times as long as wide). (VII) Dorsal carinae of hind femora in S. pyrroma sp. nov. bear three sharp protrusions, while in S. dentiumeris they bear three slight and blunt protrusions (“posterior femoral margins lightly bilobate above” according to Hancock (1907)). (VIII) Distal pulvilli of the hind tarsus S. pyrroma sp. nov. distinctly elongated and blunt, while in S. dentiumeris it is sharp. (IX) New species is larger than S. dentiumeris (female BL 16.10 mm in S. pyrroma sp. nov., 13.90 mm in female S. dentiumeris ; female PL 30.00 mm in S. pyrroma sp. nov., 25.70 in female S. dentiumeris ). (X) In S. pyrroma sp. nov. tegmina have a clear yellow line in the dorsal part, while in S. dentiumeris they are monochromatic.

Distribution, habitat, and threats. The Hainan Amberblade Rowerhopper is endemic to the island of Hainan, PR China and for now, it is known from two localities, Ding’an (the type locality), and Wuzhi-shan Mountain ( Fig. 2 ). The species inhabits lower parts of the Wuzhi-shan, which is known as the highest mountain of Hainan, reaching up to 1,840 m in height. This species is, however, known to inhabit lower parts of the mountains, rich in creeks with stony shores, where it can be observed sitting on stones (as in Fig. 1 ), or swimming in streams. Hainan Island represents one of the biodiversity strongholds in PR China, full of primary rainforests and untouched wild habitats, which face deforestation (see Li 2012; Zhai et al. 2015; Xu et al. 2017; Zhu,2017). Taking into account that Hainan lowland ecosystems face greater threats than the mountainous ecosystems ( Wu et al. 2011) and that Scelimena pyrroma sp. nov., is most likely a lowland species, we assume it could indeed be threatened by human development in Hainan. The new species is only known from two localities in Hainan so we assess it as Near Threatened since it has a small area of occupancy (AOO) (less than 100 km ²), it occurs at only two locations (about 100 km from each other), and a single threatening event (lowland habitat destruction) could rapidly drive this species to become Vulnerable ( IUCN 2022). This pygmy grasshopper may be threatened in the parts of its distribution area (Ding’an for example) by the replacement of local vegetation with croplands. Luckily, the other of the two localities we report the species from, the Wuzhi National Nature Reserve, is under strict government protection and the species can be regarded as safe in this very location.

Species description based on holotype, paratype, and an additional female from iNaturalist ( Figs. 1 , 10 , 11 ). A detailed description of Scelimena pyrroma sp. nov. was presented in the Mandarin language by Liang & Zheng (1998) under the name Scelimena dentiumeris . Herewith, we present an updated detailed diagnostic description of Scelimena pyrroma sp. nov., which is from now on the correct name for this Hainan population of Scelimena with notable metalateral tubercles. There are indeed parts of Liang & Zheng’s (1998) description that need to be amended, and the same will be true for our species description in the moment when large series will be examined by some future authors.

GENERAL APPEARANCE AND COLOURATION Description of colour pattern is based on the photograph of a living female from Wuzhishan ( Fig. 1 ). Large (pronotum length> 22 mm in males, and> 29 mm in females) and smooth (without saw-like, toothed projections or strongly tuberculated margins), amphibious species, general colour dark brown, almost black, with fine pale coloured granules all over the pronotum. This species has flashy yellowish (pale coloured) FL2, VL, MLs, and the lappets of the dorsal margins of the hind femora.

HEAD. Finely granulated. Antennae long, thin, and smooth, composed of 13 antennomeres: 1 st large scapus, 2 nd stout pedicel, 3 rd – 6 th elongated basal segments, 7 th – 8 th very elongated mid segments (more than 10 times as long as wide), 9 th – 10 th long subapical segments, 11 th – 13 th reduced apical segments. Scapus, pedicel and flagellum dark, except for the pale rings present on the end of each antennomere of the flagellum. In frontal view transverse and lateral carinae of the vertex slightly elevated, not reaching the dorsal margin of the compound eyes. Frontal costa long, bifurcating below the mid-level of the compound eye height. Facial carinae divergent in the upper fourth and then parallel. Lateral ocelli slightly below the bifurcation of the frontal costa, on each side of it. Scutellum between the facial carinae about as wide as scapus.Antennae inserted distinctly below the compound eyes. The dorsal margin of the antennal groove situated half a compound eye length below the lower margin of a compound eye. Vertex wider than a compound eye (1.25 in male, 1.5 times in female). Vertex widely U-shaped, with slightly elevated median carina. Compound eye ovoid. In dorsal view vertex indrawn, not reaching the distal margin of a compound eye. Anterior margin of the pronotum truncated, with the indrawn (concave) mid part. Median carina of the vertex short, visible only in the anterior third. Fossulae deep, present on each side of the median carina of the vertex, and anteriorly and laterally surrounded by slightly elevated lateral and transverse carinae of the vertex. Compound eyes semi-circular. Vertex wider than a compound eye (1.3 times in male, 1.5 times in female). Occipital area as wide as a half of a compound eye. In lateral view eyes semi-circular and exserted above the vertex, so the tip of the vertex and the upper part of the face are not visible. Frontal costa slightly projected forwards. Paired ocelli large, visible below the anterior portion of the lower margin of the compound eye. Palpi without strongly widened apical segments. Apical segment of the palpi hairy.

PRONOTUM. Pronotum very long (macropronotal state), surpassing abdominal apex for about 1.5 length of a hind femur. In frontal view only three projections are visible: ventrolateral projection of the lateral lobes (VL) projected outwards as a spine, yellow in colour; the second frontolateral projections (FL2) are strongly projected behind the head; and metalateral angles (ML or ML1) have projections with a tubercle at the tips. In lateral view. Prozona directed slightly upwards, not straight. Frontomedial projection (FM) minute, but visible; prozonal carinae visible, of weak texture and without tubercles; promedial projection (PM) minute, visible as a weak and blunt elevation. Second frontolateral projections (FL2) strongly projected forwards, yellow, surpassing the front margin of the pronotum. Ventral margin of the lateral lobe smoothly curved cephalad, ventrolateral spine (VL) sharp. Ventral sinus the same shape as tegminal sinus (that is subrectangular), but slightly larger. Infrascapular area rectangular, not as wide as tegmen. First (MM1) and second metamedial (MM2) projections weak, subtriangular, but (barely) visible. First (MML1) and the second (MML2) metamediolateral projections very weak and hardly recognizable, but present as small elevations on the dorsum. The main metalateral tubercle (ML or ML1) excised, oval, and yellow; while second (ML2) and third metalateral tubercles (ML3) sometimes present behind ML, visibly smaller than ML. Pronotum slightly dented after MML1 and MML2, straight afterwards. In dorsal view pronotum finely granulated, with larger tubercles on the carinae (no tubercles on the median carina). Anterior margin of the pronotum truncated. Median carina of the pronotum continuous from the anterior margin to the tip. Prozonal carinae visible, parallel and of weaker texture than the median carina. Extralateral projections anteriorly armed with strongly projected second frontolateral projections (FL2), which are yellow. Frontomedial projection (FM) minute, promedial projection (PM) minute – present as a weak and blunt elevation, first (MM1) and the second metamedial (MM2) projections even weaker. Y-shaped carinulae present in the interhumeral region. First (MML1) and the second (MML2) metamediolateral projections very weak and hardly recognizable, but present as small elevations on the dorsum. Humeral angles obliquely angular, armed with blunt metalateral (ML) tubercles, sometimes also with weak ML2 and ML3 on the external lateral carina behind them. Pronotum exceeding the knees of the hind femur for almost one whole hind femur length. Paranota armed with ventrolateral spines of variable length, which are always strongly curved forwards and are usually paler in colour than the rest of the pronotum.

WINGS. Tegmenula (= pygmy grasshoppers tegmina, fore wings) and alae (hind wings) present. Tegmina scale-like, ovoid, reaching the proximal third of the hind femur length. Alae elongated, visible in lateral view, almost reaching the tip of the pronotum (for 1-2 mm shorter than it).

LEGS. Fore femur elongated. Tibia black, smooth, rectangular in cross section. Proximal segment of the fore tarsus short, while the distal segment is elongated, dark and with a pale ring in the middle. Mid femur elongated. Tibia dark, smooth, rectangular in cross section. Proximal segment of the mid tarsus also short, while the distal segment elongated, dark and with a pale ring in the middle, as well. Hind femur elongated, about 3.7 times as long as wide. Dorsal margin of the hind femur with several pale coloured lappets. Ventral margin of the hind femur with three clearly visible teeth around the middle, and a barely visible one near the knee. Genicular and antegenicular teeth recognizable, but small and blunt. Tibia distally widened. Fore segment of the hind tarsus widened, pulvilli short and pointed. First tarsal segment longer than the third. Distal tarsal segment pale coloured, almost white.

OVIPOSITOR. Ovipositor with elongated valvulae.

Variability. Males are, as in other Scelimena species, visibly smaller than females ( Table 2 ). Colouration within the species varies, as well as prominence of the frontomedial and the prominence and the number metalateral tubercles. Second frontomedial projections can be longer or shorter, more or less pointed. Holotype female has, besides strong metalateral tubercles, one more pair of weak tubercles just behind them. VL spine can be more or less pointed, shorter or longed, but is always strongly curved and directed forwards. Variation in this Hainan endemic species resembles the variability of Scelimena novaeguineae ( Bolívar, 1898) , reported by Tumbrinck (2018). In S. novaeguineae , some specimens have strong humeral teeth, while others have blunt warts; some have a single metalateral plate, others have more than one metalateral projections, sometimes before the shoulders. Future investigation should investigate whether these variations represent forms of a single species, or there is a whole hidden complex of several Scelimena species in Hainan.

Figures

FIGURE 1. Hainan Amberblade Rowerhopper, Scelimena pyrroma sp. nov. a living female on a rock next to a creek in a lowland ecosystem (PR China: Hainan: Wuzhi National Nature Reserve). Photo by Fan Gao.

FIGURE 2. Habitat of Scelimena pyrroma sp. nov. in Wuzhi National Nature Reserve — a rocky stream in lowland rainforest. Photographed by Fan Gao.

FIGURE 10. Type specimens of Scelimena pyrroma sp. nov. (a, c, d, e) Holotype female; (b, f, g, h) Paratype male. (a) and (b) head frontal view; (c) and (f) dorsal view; (d) and (g) lateral view); (e) and (h) labels.

FIGURE 11. Drawings of Scelimena pyrroma sp. nov. (a) dorsal view coloured after the specimen on Figure 1., (b) lateral view, holotype, (c) dorsal view, holotype, (d) frontal view, holotype, (e) brightened version of the dorsal frontal portion of the body coloured after the specimen on Figure 1. Drawings by Chuangyu Lao.

FIGURE 12. Scelimena dentiumeris Hancock, 1907 from Borneo identified by Günther. A) lateral view, B) dorsal view, C) labels. Photography NHMUK, copyright The Trustees of the Natural History Museum, London.