Philippine Journal of Science 150 (4): 809-816, August 2021 ISSN 0031 - 7683 Date Received: 19 Jan 2021 Distribution of the Mindanao Spiky-helmed Pygmy Grasshopper Misythus echinatus (Stål, 1877) (Tetrigidae: Cladonotini) Romeo R. Patano Jr.1,2*, Alma B. Mohagan1,2, and Victor B. Amoroso1,2 1Center for Biodiversity Research and Extension in Mindanao 2Department of Biology, College of Arts and Sciences Central Mindanao University, Musuan, Maramag, Bukidnon 8710 Philippines Misythus Stål, 1877 (Tetrigidae: Cladonotinae) is a diverse genus of pygmy grasshoppers with 27 species and two subspecies, all of which are endemic to the islands of the Philippines. Here, the emphasis is put on the spiky wingless pygmy grasshopper, Misythus echinatus (Stål, 1877). The species is endemic to northern Mindanao and adjacent islands (Siargao Island, Bucas Island, Surigao, Iligan, and Butuan). The last published records originate from 1916 and most of the specimens hitherto reported lacked habitat descriptions and especially images of the species in its natural environment. In this study, we report the species for the first time from Bukidnon and Davao regions; we update its distribution in Mindanao and describe its natural habitat with supporting images. An updated distribution map for this species is provided, together with detailed measurements of male and female specimens, in order to make a comparison between different populations possible. Keywords: endemic species, measurements, montane forest, Mt. Malimumu, pronotum, ultramafic substrate INTRODUCTION by having high and warty pronotal projections and are wingless (Tumbrinck 2014). The Philippine endemic genus Misythus Stål, 1877 belongs to the family Tetrigidae, subfamily Cladonotinae The genus Misythus includes 27 species and two subspecies (Cigliano et al. 2021), tribe Cladonotini (Bhaskar et al. – all found in the Philippines. This genus is unique 2020; Tumbrinck et al. 2020). Formerly known from concerning the diversity of pronotum (Hebard 1923). genus Cladonotus Serville, 1838 endemic to Sri Lanka Misythus echinatus is a Mindanao-endemic species but (Stål 1877; Castro de Elera 1895). Members of this for its very holotype, no specified locality is known. The subfamily are characterized mainly by having widened specimen originated from the Semper’s collection (Stål scutellum (Tumbrinck 2014). There are more than 1,950 1877). Specimens with exact localities were first thoroughly known species within the family, and new species are studied by Hebard (1923) based on collections of W.F. discovered every year in Mindanao – for example, from Boettcher and C.F. Baker. Based on these collections, all the genus Cladonotella (Tan et al. 2019), Arulenus (Skejo specimens of the species were collected in Mindanao – and Caballero 2016), and Tegotettix (Patano et al. 2021). specifically from Siargao Island (1916), Bucas Island, Species under the genus Misythus are characterized Surigao, Butuan, and Iligan lacking exact coordinates, habitat descriptions, and supporting images. For a century, *Corresponding Author: [email protected] no more records were reported on the species. 809 Philippine Journal of Science Patano et al.: Distribution of Misythus Vol. 150 No. 4, August 2021 echinatus Stål, 1877 Thus, this short study updates the distribution and and random sampling methods was implemented in the describes the habitat of M. echinatus. This study study. The collection of specimens was conducted along an provides a new record of the species in the region where established 2-km transect in each site covering 10 m x 5 m Spartolus pugionatus, Diotarus verrucifer, and Arulenus on both sides. A study site is described accordingly through validispinus were recently recorded from the neighboring percentage estimations, in which dominant plant species in locality and mountain ranges (Mohagan et al. 2020a, b, c). the area were identified (VBA: one of the authors) using Co’s Digital Flora website (Pelser et al. 2011 onwards). Male and female specimens of Misythus echinatus were MATERIALS AND METHODS collected through handpicking whenever encountered during the diurnal (07:00–15:00h) and nocturnal (17:00– 22:00h) periods. They were then put in vials filled with Entry Protocol and Permits 95% ethyl alcohol for preservation. Specimens were air- Obligatory permits such as an approved gratuitous permit dried and mounted. Images of the species were taken using (GP) were obtained from the Department of Environment a DSLR Canon camera combined with a stereomicroscope. and Natural Resources in compliance with Republic Final images of the species were edited using licensed Act No. 9147 for the collection of the specimens and Adobe Photoshop CS software. The ocular micrometer Institutional Animal Care and Use Committee (IACUC) and digital caliper were used to measure the specimens. permit for animal handling. The standard methodologies of Skejo and Bertner (2017), Tumbrinck and Skejo (2017), Skejo (2017), and finally Field Sampling, Collection of Specimens, Muhammad et al. (2018) in gathering measurements and Photography, and Measurements describing pronotal projections were employed. A male The study was conducted in the lower and upper specimen of the species from the Orthoptera Species File montane forest of Mount Malimumu, Sitio Nabangkal, was also measured for comparison. Barangay Magkalungay, San Fernando; Mt. Ulahingan, The following measurements were taken: body length Sitio Tagumpay, Barangay Datu Salumay; and Mount (BL) (from the anterior end of the pronotum to the Kitanglad Range, Kaatuan, Lantapan, Bukidnon (Figure posterior end of the subgenital plate), pronotum length 1). A combination of standard belt-transect, opportunistic, Figure 1. Map of the Philippines (A) and Mindanao (B) showing the updated distribution of Misythus echinatus (Stål, 1877). Localities are also shown in Table 1. 810 Philippine Journal of Science Patano et al.: Distribution of Misythus Vol. 150 No. 4, August 2021 echinatus Stål, 1877 (PL), pronotum lobe width (PLW), pronotum height (PH), known not to include detailed labels (“Philippines” only). fore femur length (FFL), fore femur width (FFW), mid Thus, more species from the collection need to be studied femur length (MFL), mid femur width (MFW), hind femur in order to find out which region did Semper collected in length (HFL), hind femur width (HFW), vertex width (retrieved from the Orthoptera Species File). (VW), compound eye width (CEW), abdominal length (AL), and antennal length (AnL). The specimens collected Diagnosis of the species. The species can be easily and examined in this study are deposited in Central distinguished by its bulky appearance with irregular Mindanao University, University Museum, Zoological positions of heavy and stout spines scattered throughout Section, Tetrigidae Collection. All measurements are its pronotum (Figure 2), head (Figures 3A–D), and legs, shown in millimeters. especially femora (Figures 3E–G). Other species of the genus have different pronotal projections [compare with Hebard (1923)] – usually with long frontal part or compresso-elevated dorsum. RESULTS AND DISCUSSION Family Tetrigidae Rambur, 1838 Subfamily Cladonotinae Bolívar, 1887 Tribe Cladonotini Bolívar, 1887 Misythus echinatus (Stål, 1877) This species is originally known from the genus Cladonotus Sausurre, 1862 endemic to Sri Lanka (Stål 1877; Castro de Elera 1895). It was then moved to the genus Misythus Stål, 1877, which is a quite large genus with 27 species and two subspecies all known in the Philippines (Hebard 1923). Members of the genus are non-flyers and can be easily distinguished by having frontomedial projection considerably produced forward Figure 2. Misythus echinatus (Stål, 1877). Dorsal view and lateral and presence heavy and stout spines through their legs, view of male (A and B) and female (C and D). Scale pronotum, and head (Hebard 1923). bar: 10 mm. Misythus echinatus (Stål, 1877) is one of those spinose species. The species is recorded in the Philippines and some records might be in Luzon but still needs validation as more likely it was misidentified (Bruner 1915; Günther 1938; Blackith 1992). As being recorded almost a century ago, there is no known ecological and updated distribution of the species. Material examined. Philippines • (2/2) 1♂1♀ 1 and 2 – Bukidnon, San Fernando, Barangay Magkalungay, Sitio Nabangkal, Mount Malimumu, 7°52’50.58” N, 125°24’32.64” E, 1,074 masl, 22 Aug 2020, AM-011; (1/1) 1♂ 3 – Mt. Ulahingan, Sitio Tagumpay, Barangay Datu Salumay, 07°28’29.89”N, 125°16’36.77”E, 1,300 masl, February 2019, AM-010; (1/1) 1♀ 4 – Mount Kitanglad Range, Kaatuan, Lantapan, Bukidnon, 08°06’29.54”N, 124°56’0.61”E, 1,600 masl, September 2018, A.B. Mohagan, R.R. Patano Jr., and V.B. Amoroso, Central Mindanao University, University Museum, Zoological Section; (1/1) 1♂ (holotype) 5 – the Philippines with no Figure 3. Misythus echinatus (Stål, 1877): A) face in frontal view; specific locality (Semper’s collection). B) head in dorsal view; C) mouthparts in ventro-frontal view; D) head and anterior part of pronotum in lateral On the type locality. The Philippines is simply noted, as view; E) fore, F) middle, and G) hind femora in lateral there is no specified locality for the holotype label. The views; H) abdominal apex and subgenital plate in ventral holotype originated from Semper’s collection retrieved view; I) antennae; J) posterior tibia and tarsus in lateral at Orthoptera Species File website, and the collection is view. Scale bars: 1 mm. 811 Philippine