FINAL INSTAR CATERPILLAR AND METAMORPHOSIS OF LEBEDA COGNATA GRÜNBERG, 1913 IN SINGAPORE (LEPIDOPTERA: LASIOCAMPIDAE)

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NATURE IN SINGAPORE 2012 5: 129 140 Dte of Puliction: 4 My 2012 Ntionl University of Singpore FINAL INSTAR CATERPILLAR AND METAMORPHOSIS OF LEBEDA COGNATA GRÜNBERG, 1913 IN SINGAPORE (LEPIDOPTERA:

1 NATURE IN SINGAPORE : Dte of Puliction: 4 My 2012 Ntionl University of Singpore FINAL INSTAR CATERPILLAR AND METAMORPHOSIS OF LEBEDA COGNATA GRÜNBERG, 1913 IN SINGAPORE (LEPIDOPTERA: LASIOCAMPIDAE) Tzi Ming Leong 1* nd Mishk Shunri 2 1 Deprtment of Biologicl Sciences, Ntionl University of Singpore 14 Science Drive 4, Singpore , Repulic of Singpore 2 Centrl Nture Reserve, Ntionl Prks Bord 601 Islnd Clu Rod, Singpore , Repulic of Singpore ( * Corresponding uthor: njrn@gmil.com) ABSTRACT. The finl instr cterpillr of Leed cognt Grünerg is descried nd illustrted from successful ttempt t rering to metmorphosis. Detils of the morphology of the lrv, cocoon, nd pup re provided. Sexul dimorphism in this species is highlighted, with comprtive mle exmples from Singpore nd Borneo. KEY WORDS. cterpillr, pup, Lsiocmpide, Leed cognt INTRODUCTION The lsiocmpid moth Leed cognt ws first descried y Grünerg (1913) sed on mle type specimen from Kinlu, Borneo. The geogrphic rnge of this species includes Borneo, Sumtr, Peninsulr Mlysi, Singpore, nd northern nd southern Thilnd (Hollowy, 1976; Zolotuhin & Pinrtn, 2005). It is primrily n inhitnt of lowlnd forests, nd in Peninsulr Mlysi nd Sumtr, replced in the highlnds y the montne species, Leed noilis Wlker (Hollowy, 1987, Zolotuhin & Pinrtn, 2005). A rief description of its lrve, ccompnied y n illustrtion of mture cterpillr, ws previously provided y Brlow (1982: 50, pl. 50, Fig. 1). However, there ppers to e no prior illustrtions of its pup. Fig. 1. A mture cterpillr (hed towrds right, totl length c. 110 mm, possily penultimte instr) of Leed cognt dopting its defensive posture when encountered t McRitchie Reservoir forest on the night of 19 Aug.2008 (c hours). 129

2 Leong & Mishk.: Finl Instr Cterpillr of Leed cognt in Singpore OBSERVATIONS Within the Centrl Ctchment Nture Reserve of Singpore, the mture cterpillrs of Leed cognt hve een occsionlly encountered, often s single individuls resting verticlly on tree trunks. Despite their lrge size ( mm long), they cn e very well cmouflged ginst the rk, especilly with their shdes of grey-rown, nd their overll outline disrupted y dense rrngement of fine sete. Usully resting motionless y dy, the cterpillrs re nocturnl nd ctive t night. On the night of 19 Aug.2008 (c hours), mture cterpillr (totl length c. 110 mm) ws ctively crwling long rnch t eye-level, within the McRitchie Reservoir forest (Fig. 1). When pproched for closer exmintion, it immeditely elevted its nterior segments nd tucked in its hed s defensive posture. This exposed the dense rows of protective spines long the nterior mrgins of its thorcic segments. The sheer size of this cterpillr, s well s its formidle rmour of shrp spines, ws sufficient deterrence to wrn the oservers (nd potentil predtors) to keep sfe distnce. Hence, the cterpillr ws not collected. Fig. 2. Lterl () nd dorsl () views of finl instr cterpillr (hed towrds top, totl length: 135 mm, width: 18 mm) of Leed cognt oservd t the Bukit Timh Nture Reserve on 25 Nov

NATURE IN SINGAPORE 2012 At the Bukit Timh Nture Reserve (BTNR), finl instr cterpillr ws encountered while it ws crwling long the ground eside forest tril on the evening of 25 Nov.2011.

3 NATURE IN SINGAPORE 2012 At the Bukit Timh Nture Reserve (BTNR), finl instr cterpillr ws encountered while it ws crwling long the ground eside forest tril on the evening of 25 Nov With some courge, it ws crefully collected to e rered in cptivity. At rest, it plstered itself ginst rnch nd remined solutely still y dy. Its totl length ws 135 mm, nd ody width t mid-section ws 18 mm. It ws n overll ple grey, with symmetricl, drk rown nds nd streks long its dorsum nd flnks (Fig. 2). At the front end, its hed ws not redily distinguishle, s it ws mostly oscured y dense, fine sete originting from T1 nd T2 (Fig. 3). Along the dorsl mrgin of T1, row of fine, sptulte sete projected ove its hed. The pir of pinkish rown spircles, outlined with lck, ws visile t T1. Along its dorsum, there ws dense row of rerwrd-pointing, drk red spines long the nterior mrgin of ech segment (Fig. 4). In the middle of the segment ws row of smll, sptulte, light-yellow sete. Along its flnks, there ws pir of prominent ventrolterl protuernces per segment, situted elow ech spircle (Fig. 5). Originting from these ulous structures were two types of sete: (i) long nd fine, nd (ii) short nd sptulte. Its posterior-most segments (including nl segment nd nl prolegs) were mostly chlky white, with symmetricl rown ptterns nd speckles (Fig. 6). In cptivity, the cterpillr did not feed, s it rested y dy nd pced out restlessly t night, displying possile signs of pre-pupl ehviour. On the morning of 27 Nov.2011, the cterpillr ws found to hve crwled into curled, dried lef. Upon closer inspection, the nrrow gps of the dried lef hd egun to e seled y strong strnds of silk. Puption ws complete within the following dys nd creful exmintion of the dried lef reveled tht it ws lnketed with short, shrp spines over its entire surfce (Fig. 7). These spines were ll directed outwrds nd clerly re-employed y the cterpillr to ensure continued protection over the course of its pupl phse. On 8 Dec.2011, the cocoon ws crefully dissected in order to exmine the pup within. Attched to the inner surfce of the dried lef ws dense meshwork of long, fine sete (s in Fig. 5), intertwined with strong, silk strnds. At one corner of the cocoon, the shriveled lrvl skin of the finl instr ws found nd removed for preservtion (Fig. 8). The hed cpsule ws clerly visile now nd exhiited deep rown nds nd lotches. Fig. 3. Dorsl close-up of the cterpillr hed, lrgely oscured y forwrd-directed sete, originting from T1 nd T2. 131

The nterior mrgin of ech segment is rmed with dense row of short, stiff spines pointing ckwrds.

4 Leong & Mishk.: Finl Instr Cterpillr of Leed cognt in Singpore Fig. 4. Dorsl close-up of mid-section of cterpillr (hed towrds right). The nterior mrgin of ech segment is rmed with dense row of short, stiff spines pointing ckwrds. Posterior to this is row of short, sptulte, yellowish sete. Fig. 5. Lterl close-up of cterpillr (hed towrds right). Note prominent, ventrolterl protuernce t ech segment, from which rdited long, fine sete, s well s shorter, sptulte sete. 132

NATURE IN SINGAPORE 2012 Fig. 6. Close-up of posterior segments. The pup ws temporrily extrcted for detiled mesurements nd exmintion (Fig. 9). Its totl length ws 63 mm; width, 21 mm; nd depth, 21 mm.

5 NATURE IN SINGAPORE 2012 Fig. 6. Close-up of posterior segments. The pup ws temporrily extrcted for detiled mesurements nd exmintion (Fig. 9). Its totl length ws 63 mm; width, 21 mm; nd depth, 21 mm. It hd roust form nd ws well rounded t oth ends. Its overll colour ws deep, reddish rown. The dominl segments were flexile nd rotted out when distured. Dense rrngements of short, golden sete were present on the picl region of its hed, s well s long the posterior mrgins of its dominl segments. At its posterior, silk strnds were securely fstened to the cremster. After documenttion of this pup, it ws then replced into the cocoon to continue with its development. On the morning of 22 Dec.2011, femle moth ws found to hve eclosed. Its wings hd chieved full extension nd the nterior mrgins of the hindwings were positioned well in front of the forewings, in typicl lsiocmpid fshion (Fig. 10). Its wings were uniform chocolte-rown, with fint grey, trnsverse nds nd white, semilunr discl spot on the forewing. At its nterior, its lunt hed ws n shy grey (Fig. 11). Its ntenne were pectinte, ut with significntly reduced pectintions. The specimen ws lter preserved s voucher t the Zoologicl Reference Collection (ZRC) of the Rffles Museum of Biodiversity Reserch (RMBR), Ntionl University of Singpore. It ws ctlogued s ZRC.LEP.372 (ody length: 62 mm, ody width: 21 mm, forewing length: 69 mm, ntenn length: 16 mm). Prior to preservtion, the femle moth hd extruded seven eggs. They were ellipticl ( mm), light rown, with white picl ring encircling rown spot (Fig. 12). 133

2011 nd constructed its cocoon within over the next few dys ().

6 Leong & Mishk.: Finl Instr Cterpillr of Leed cognt in Singpore Fig. 7. The cterpillr hd crwled into dried, curled lef on 27 Nov.2011 nd constructed its cocoon within over the next few dys (). Upon completion of its cocoon, it could e seen tht multiple shrp spines (s in Figs. 4, 5) were incorported into its exterior, forming formidle, deterrent rrier (). 134

7 NATURE IN SINGAPORE 2012 Fig. 8. Shriveled lrvl skin of the finl instr, removed from within the cocoon upon dissection. Pronounced sexul dimorphism is witnessed in Leed cognt, with mles eing smller, ut possessing distinctly ipectinte ntenne. The forewing ptterns of mles lso demonstrte greter contrst (Fig. 13). A single mle specimen from Singpore ws exmined (ZRC.LEP.374, ody length: 43 mm, ody width: 9 mm, forewing length: 35 mm, ntenn length: 11 mm). It ws collected during Ntionl Prks Bord survey of Nee Soon Swmp Forest on 17 Jun Mles hve lso een previously encountered t the BTNR on t lest two occsions: 12 Dec.2007 nd 20 Jun.2010 (Fig. 14). They were proly ttrcted y the night lights of the BTNR Visitor Centre. At rest, their wings were folded over their odies, with the domen protruding just eyond the wing tips. A Bornen mle exmple ws exmined t the Bukit Kn Reserch Sttion (Bintulu Division, Srwk, Est Mlysi) on 31 Mr.2007 t c hours (Fig. 15). It ws in the wrm-up process of fluttering its wings, in preprtion to tke flight. During the upstroke, the contrsting underwing ptterns of drk versus light rown could e oserved. ACKNOWLEDGEMENTS We re grteful to Jeremy Hollowy for confirming the identity of the moth, s well s Lu Hui Kheng for grnting ccess to exmine nd photogrph the mle specimen t the Zoologicl Reference Collection, Rffles Museum of Biodiversity Reserch. A lepidopterist reviewer kindly provided useful suggestions tht refined the originl mnuscript. LITERATURE CITED Brlow, H. S., An Introduction to the Moths of South Est Asi. The Mlyn Nture Society, Kul Lumpur. vii pp., 50 colour pls. Grünerg, K., Neue Indo-Austrlische Lsiocmpiden. Entomologische Rundschu, 30: Hollowy, J. D., Moths of Borneo, with Specil Reference to Mount Kinlu. Mlyn Nture Society, Kul Lumpur. viii pp. Hollowy, J. D., The Moths of Borneo, Prt 3. Superfmily Bomycoide: Fmilies Lsiocmpide, Eupterotide, Bomycide, Brhmeide, Sturniide, Sphingide. Southdene, Kul Lumpur. 199 pp. Zolotuhin, V. V. & A. Pinrtn, Moths of Thilnd, Volume 4: Lsiocmpide. Brothers of Sint Griel in Thilnd, Bngkok. 205 pp. 135

Note rrngement of short, golden sete t its hed region,

8 Leong & Mishk.: Finl Instr Cterpillr of Leed cognt in Singpore c Fig. 9. Ventrl (), lterl (), nd dorsl (c) views of pup (length: 63 mm, width: 21 mm, depth: 21 mm). Note rrngement of short, golden sete t its hed region, nd long the posterior mrgins of dominl segments. Remnnt strnds of cocoon silk were still ttched to its cremster. 136

9 NATURE IN SINGAPORE 2012 Fig. 10. Recently eclosed femle moth (ZRC.LEP.372, ody length: 62 mm, forewing length: 69 mm) with outstretched wings on 22 Dec

10 Leong & Mishk.: Finl Instr Cterpillr of Leed cognt in Singpore Fig. 11. Frontl () nd lterl () close-ups of femle moth (s in Fig. 10). Fig. 12. Extruded eggs ( mm) of the femle moth (ZRC.LEP.372). 138

NATURE IN SINGAPORE 2012 Fig. 13. Mle () nd femle () specimens of Leed cognt from Singpore.

374, ody length: 43 mm, ody width: 9 mm, forewing length: 35 mm, ntenn length: 11 mm) ws

372, ody length: 62 mm, ody width: 21 mm, forewing length: 69 mm, ntenn length: 16 mm) is the

11 NATURE IN SINGAPORE 2012 Fig. 13. Mle () nd femle () specimens of Leed cognt from Singpore. The mle specimen (ZRC.LEP.374, ody length: 43 mm, ody width: 9 mm, forewing length: 35 mm, ntenn length: 11 mm) ws collected from Nee Soon Swmp Forest in Jun The femle specimen (ZRC.LEP.372, ody length: 62 mm, ody width: 21 mm, forewing length: 69 mm, ntenn length: 16 mm) is the sme individul fetured in Fig. 10. Fig. 14. Exmples of mles (ody lengths: c. 45 mm) encountered t the Visitor Centre of the Bukit Timh Nture Reserve on 12 Dec.2007 (), nd 20 Jun.2010 (). 139

12 Leong & Mishk.: Finl Instr Cterpillr of Leed cognt in Singpore Fig. 15. Dorsl () nd lterl () views of mle Leed cognt (ody length: c. 45 mm) encountered in Srwk, Borneo on 31 Mr.2007 (c hours). 140

INTRODUCTION OBSERVATIONS

INTRODUCTION OBSERVATIONS NATURE IN SINGAPORE 2011 4: 369 375 Dte of Puliction: 28 Novemer 2011 Ntionl University of Singpore OBSERVATIONS OF PUPAL ECLOSION AND PHEROMONE RELEASE IN THE OLEANDER HAWKMOTH, DAPHNIS NERII (LINNAEUS,