Heterometrus

Heterometrus, whose members are also known by the collective vernacular name giant forest scorpions, is a genus of scorpions belonging to the family Scorpionidae. It is distributed widely across tropical and subtropical southeastern Asia, including Indonesia, Brunei, Malaysia, Myanmar, Philippines, Singapore, Cambodia, Laos, Thailand, Vietnam, India (Nicobar Islands, Andaman Islands), and China (Hainan).[2][3] It is notable for containing some of the largest living species of scorpions.

Heterometrus
Heterometrus spinifer
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Class: Arachnida
Order: Scorpiones
Family: Scorpionidae
Genus: Heterometrus
Ehrenberg, 1828
Type species
Buthus (Heterometrus) spinifer
Diversity
8 species
Synonyms
  • Palamnaeus Thorell, 1876

Taxonomy

The genus was introduced by C.G. Ehrenberg (in Hemprich & Ehrenberg, 1828), originally as a subgenus of the genus Buthus.[4] It was elevated to genus rank by F. Karsch in 1879.[1] H.W.C. Couzijn (1978, 1981)[5][6] subdivided the genus into several subgenera, but F. Kovařík (2004)[2] synonymized these subgenera with the nominal genus. In 2020 the genus was reviewed by L. Prendini & S. F. Loria, three of the former subgenera were revalidated and elevated to genera and one valid subgenus was elevated to genus rank, species were transferred to appropriate genera, resulting in 28 new combinations.[3]

Diversity

The content of this genus may vary, depending on the authority. Eight species are known, many of which are quite similar in appearance:[7]

General characteristics

Members of Heterometrus are generally large-sized scorpions (100–200 mm or about 4-8 in total length). Coloration is dark in most species, often uniformly brown or black, sometimes with a greenish shine, with brighter-colored telson, walking legs, and/or pedipalp pincers in some species. The scorpions are heavily built with especially powerful and globose pedipalp pionkes, broad mesosomal tergites and a proportionally slender and thin metasoma. The telson is proportionally small and the stinger is often shorter than the vesicle. The cephalothorax and mesosoma are largely devoid of carinae and granulation and the median eyes are situated in a small, lenticular depression on the cephalothorax. Some species are parthenogenic.[2][6]

Orthobothriotaxy type C. Pedipalp femur with three trichobothria and pedipalp patella consists with 19 trichobothria. Pedipalp chela with 26 trichobothria. Retrolateral pedal spurs are absent. Stridulatory organ is located on the opposing surfaces of pedipalp coxa and first leg.[8]

Toxicity
Heterometrus laoticus at Khao Yai National Park, Thailand

As in other genera of the Scorpionidae, the symptoms from Heterometrus envenomations are rather mild and no human fatalities are known.[6] The sting causes local pain, inflammation, oedema, swelling, and redness of the skin, lasting for hours to a few days. Plant extracts known in the traditional Thai medicine as natural scorpion venom antidotes are effective as symptomatic treatment of H. laoticus stings.[9] The protein heteroscorpine-1 was found the major component of the venom in H. laoticus.[10]

Habitat for the scorpion

Species of Heterometrus live in vegetated, often forested, humid regions with subtropical to tropical climates. As most scorpions, they are predominantly nocturnal and hide in burrows, below logs, and in leaf litter.

In captivity

Due to their impressive size, low toxicity, and docile behavior, species of Heterometrus are popular pet scorpions. Unlike many other scorpions, they can be kept in pairs or small groups.

References
  1. Karsch, F. (1879). "Skorpionologische Beiträge I.". Mitteilungen des Münchener Entomologischen Vereins (in German). 3: 6–22.
  2. Kovařík, F. (2004). "A review of the genus Heterometrus Ehrenberg, 1828, with descriptions of seven new species (Scorpiones, Scorpionidae)" (PDF). Euscorpius. 15: 1–60.
  3. Prendini, Lorenzo; Loria, Stephanie F. (14 October 2020). "Systematic revision of the Asian forest scorpions (Heterometrinae Simon, 1879), revised suprageneric classification of Scorpionidae Latreille, 1802, and revalidation of Rugodentidae Bastawade et al., 2005". Bulletin of the American Museum of Natural History. 442. American Museum of Natural History. 442: 1–480. doi:10.1206/0003-0090.442.1.1. ISSN 0003-0090. OCLC 613326018. S2CID 222348199.
  4. Hemprich, F.G.; C.G. Ehrenberg (1828). "Zoologica II. Arachnoidea. Plate I: Buthus; plate II: Androctonus.". Symbolae physicae seu icones et descriptiones animalium evertebratorum sepositis insectis quae ex itinere per Africam borealem et Asiam occidentalem (in Latin). Berlin: Officina Academica, Decas Prima. pp. Plates IX–X.
  5. Couzijn, H.W.C. (1978). "The method of polythetic analysis applied to a source of taxonomic difficulty: The genus Heterometrus H. & E., 1828 (Scorpionidae)". Symposium Zoological Society London. 42: 327–333.
  6. Couzijn, H.W.C. (1981). "Revision of the genus Heterometrus Hemprich & Ehrenberg (Scorpionidae, Arachnoidea)" (PDF). Zoologische Verhandelingen. 184: 1–196.
  7. Rein, J.O. (2022). "Scorpionidae Latreille, 1802". The Scorpion Files. Norges Teknisk-Naturvitenskapelige Universitet. Retrieved 9 April 2022.
  8. Charles University; Kovařík, František; Lowe, Graeme; Monell Chemical Senses Center; Ranawana, Kithsiri B.; University of Peradeniya; Hoferek, David; Jayarathne, V. A. Sanjeewa; University of Peradeniya (2016). "Scorpions of Sri Lanka (Scorpiones: Buthidae, Chaerilidae, Scorpionidae) with description of four new species of the genera Charmus Karsch, 1879 and Reddyanus Vachon, 1972, stat. n". Euscorpius. 2016 (220): 1–133. doi:10.18590/euscorpius.2016.vol2016.iss220.1. Retrieved 2021-08-29.
  9. Uawonggul, N., Chaveerach, A., Thammasirirak, S., Arkaravichien, T., Chuachan, C., & Daduang, S. (2006). "Screening of plants acting against Heterometrus laoticus scorpion venom activity on fibroblast cell lysis" (PDF). Journal of Ethnopharmacology. 103 (2): 201–207. doi:10.1016/j.jep.2005.08.003. PMID 16169172. Archived from the original (PDF) on 2011-07-22.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  10. Uawonggul, N., Thammasirirak, S., Chaveerach, A., Arkaravichien, T., Bunyatratchata, W., Ruangjirachuporn, W., Jearranaiprepame, P., Nakamura, T., Matsuda, M., Kobayashi, M., Hattori, S., & Daduang, S. (2007). "Purification and characterization of Heteroscorpine-1 (HS-1) toxin from Heterometrus laoticus scorpion venom". Toxicon. 49 (1): 19–29. doi:10.1016/j.toxicon.2006.09.003. PMID 17056081.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  • Keeping instructions for H. spinifer and H. laoticus. Exotic Pets
  • Images and descriptions of various species of Heterometrus. Mes Scorpions
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.