Article

Millipedes

From Munshipedia, the MBRAS digital historical encyclopedia

Millipedes

Taxonomic Position and Morphology

Millipedes (Class Diplopoda) are invertebrate animals found in all temperate and tropical regions, herbivorous, slow-moving, and incapable of biting a human being; some species reach nearly 10 inches (254 mm) in length [1, p. 3]. The head is distinct, bearing a pair of short antennae composed of seven or eight segments and two pairs of jaws on its lower surface; the body, more or less elongated, consists of from 9 to over 100 segments, each cased in a horny ring, with two pairs of legs to most segments [1, p. 3]. Captain Stanley S. Flower, 5th Fusiliers, produced the first systematic account of the region’s millipedes in 1901, drawing on four years of fieldwork (1895–1898) across the Straits Settlements, the Native States, and Siam [1, p. 1]. His work was explicitly designed for European residents arriving from England, where such creatures were rare and harmless, who needed to identify the “wonderful variety” they encountered in daily life [1, p. 1].

Flower adopted a provisional classification following papers by R. J. Pocock and Prof. Ray Lankester published in Natural Science in 1897, placing millipedes within the Sub-kingdom Arthropoda, Section Tracheata, Subdivision Progoneata [1, p. 2]. The class is divided into three orders: Oniscomorpha (short, broad, ball-rolling “pill millipedes” of 12 or 13 segments), Limacomorpha (minute, 19 or 20 segments, no known species exceeding a quarter of an inch), and Helminthomorpha (elongate, 19 to over 100 segments, some exceeding 9¾ inches) [1, p. 5]. Within Helminthomorpha, Flower distinguished the sub-orders Colobognatha (degenerate mandibles, 30 to over 100 segments), Iuloidea (normal mandibles, 30 to over 70 segments), and Polydesmoidea (flat millipedes, always 19 or 20 segments) [1, pp. 5–6].

Distribution and Seasonal Abundance

Flower recorded millipedes across at least 15 localities in the Malay Peninsula and Siam, including Penang, Singapore, Perak, Kedah, Johore, Selangor, Bangkok, Ayuthia, Chantaboon, Kosichang, and the Dong Phya Phai [1, pp. 1]. The largest millipede he measured was Spirostreptus vittatus at 248 mm from the Kuala Kangsa Pass, Perak [1, p. 9]. Native names include Malay gongok and ulat-bulan, Siamese king keu, and Jakan gr-gok [1, p. 3].

Seasonal variation proved dramatic. On the island of Kosichang in the Gulf of Siam, Flower observed in August 1897 that “the chief living feature of the island was the Millipedes,” with hundreds crawling from sea-level to the hilltop, including large red-brown Thyropygus, smaller grey forms, flattened Orthomorpha, and numerous Zephronia that rolled into balls when picked up [1, p. 4]. By February 1898, not a single millipede was visible abroad, though a few could be found by searching damp spots under timber and old tins [1, p. 4]. Flower noted that a locality appearing devoid of millipedes in the dry season could literally swarm with them in the wet season [1, p. 4].

Notable Species and Behaviour

Among the Zephroniidae (pill millipedes), Zephronia anthracina reached 52 mm and was recorded from Perak, while Zephronia impunctata (36 mm) was represented by a single type specimen found in the jungle near the big waterfall in the Botanical Gardens, Penang, in March 1895 [1, p. 8]. Flower obtained further Zephronia specimens from Singapore, Selangor, and Kosichang of undetermined species [1, p. 8].

Thyropygus bowringii was very plentiful in Siam during the rainy season, emerging towards evening to wander gardens and paths, occasionally entering houses; during the rest of the year it seemed to disappear entirely, presumably hiding in holes [1, p. 10]. Adults had 60 to 72 segments; the longest male measured 5¾ inches (148 mm) and the longest female 8⅝ inches (220 mm) [1, p. 10]. Flower observed that these large Thyropygus, when caught, did not passively submit but twisted about, reared up their heads, and bit with their jaws without breaking the skin, yet their vigorous resistance could alarm the uninitiated [1, p. 11]. In captivity they fed readily on bananas, one individual eating without stopping for fifteen hours on end [1, p. 11].

Flower documented the development of Orthomorpha coarctata from a 2 mm pure-white juvenile with 19 segments and fine bristles, through intermediate stages of 8 to 12 mm in which the hind portions darkened first, to an 18 mm adult of rich dark-reddish-brown above and bright yellow below, at which point the body became slightly depressed [1, p. 15]. He also observed this species in copula in Bangkok in May 1897, the males clasping by the forepart of the body and suffering themselves to be dragged along [1, p. 16].

Research and Documentation

Flower’s 1901 paper in the JSBRAS represents the foundational taxonomic survey of millipedes for the Malay Peninsula and Siam. The work was produced within the network of colonial natural history linking the Straits Settlements to the British Museum of Natural History, with R. J. Pocock serving as the principal taxonomic authority for identifications and species descriptions [1, p. 1]. Flower’s specimens were distributed between the British Museum, the Royal Siamese Museum in Bangkok, and the Raffles Museum [1, p. 1]. Several species described or first recorded in the same period—Chærilus agilis, Chærilus rectimanus, Ctenus floweri, and Oncopus alticeps—were formally named by Pocock or Cambridge, indicating that Flower’s collections directly fed into the broader taxonomic literature of the 1890s [1, pp. 34]. Flower himself acknowledged that his notes were intended to help “some more competent writer to compose a full catalogue” [1, p. 1], and indeed the paper remains the principal early reference for the region’s diplopodan fauna.

MBRAS Sources

References

  1. S.S. Flower (1901). Notes on the millipedes, centipedes, scorpions etc., of the Malay Peninsula and Siam JSBRAS 36: 1–48.