Animal Diversity Web

Ge­o­graphic Range

Pygmy slow lorises, Nyc­tice­bus pyg­maeus, are found in Viet­nam, Laos, east­ern Cam­bo­dia, and neigh­bor­ing re­gions of south­ern China (south­east Yun­nan province). It is un­clear whether pop­u­la­tions in China are na­tive or in­tro­duced. (Stre­icher, et al., 2008)

• Biogeographic Regions
• oriental
  • native

Habi­tat

Pygmy slow lorises re­side in rain­forests and de­graded habi­tats as well as bam­boo thick­ets in Viet­nam and ever­green for­est in Laos. They have been ob­served at al­ti­tudes as great as 1500 m.

Lo­cals in the Mon­dulkiri province of Cam­bo­dia sug­gest that pygmy slow lorises pre­fer thick, com­plex forested areas with bam­boo to dry dipte­ro­carp for­est, and ob­ser­va­tions con­firm their pref­er­ence of mixed de­cid­u­ous to semi-ever­green forests. In­di­vid­u­als of this species are usu­ally seen at heights of 3 to 12 m in the canopy. (Rata­jszczak, 1998; Starr, et al., 2011)

• Habitat Regions
• tropical

• Terrestrial Biomes
• forest
• rainforest

• Range elevation

  1500 (high) m

  4921.26 (high) ft

Phys­i­cal De­scrip­tion

Zo­ol­o­gist J.L. Har­ri­son de­scribes pygmy slow lorises as "rather like a child's teddy-bear." They have thick light brown to deep red­dish brown fur with a white or gray un­der­side. In­di­vid­u­als have a unique pat­tern of lighter and darker col­ored mark­ings on their face, which com­monly in­clude cir­cles around the eyes and dor­sal stripes start­ing at their crown and con­tin­u­ing down their back. Dur­ing the win­ter, these mark­ings be­come more promi­nent, and they ac­quire sil­ver tips or "frost­ing." This sea­sonal col­oration is thought to cam­ou­flage and pro­tect the an­i­mals, as, dur­ing the win­ter, they must sit in ex­posed areas such as dense scrub or in the upper branches of trees that lack fo­liage.

Like other strep­sirhine pri­mates and mem­bers of the fam­ily Lorisidae, pygmy slow lorises have: for­ward-fac­ing eyes with stereo­scopic vi­sion; a rhi­nar­ium, the moist naked sur­face around the nos­trils; a tape­tum lu­cidum, the re­flec­tive layer in the eye that im­proves night vi­sion; a split upper lip; nails on all dig­its ex­cept for a groom­ing claw on the sec­ond digit of their feet; a den­tal for­mula of 2.​1.​3.​3/​2.​1.​3.​3 with the lower in­cisors and ca­nines form­ing a tooth­comb; no tail; and re­duced sec­ond dig­its on their hands.

Pygmy slow lorises and Ben­gal slow lorises evolved from a com­mon an­ces­tor and are si­m­il­iar in ap­pear­ance. The smaller body size in pygmy slow lorises is thought to be the re­sult of char­ac­ter dis­place­ment, the ac­cen­tu­a­tion of dif­fer­ences be­tween sim­i­lar species that share the same ge­o­graphic dis­tri­b­u­tion.

Pygmy slow lorises mea­sure 15 to 25 cm in length and weigh from 120 to over 500 g (av­er­age 400 g). Males are gen­er­ally larger than fe­males. Mem­bers of this species can re­tard their growth if en­vi­ron­men­tal con­di­tions are not fa­vor­able. If their diet is re­stricted, they lose their ju­ve­nile fur and at­tain adult den­ti­tion be­fore at­tain­ing adult size.

Pygmy slow lorises pro­duce a toxin from mod­i­fied sweat glands lo­cated near their el­bows. They have been ob­served lick­ing the­ses glands when alarmed. Their bite can be dan­ger­ous to hu­mans; the only ac­count of a pygmy slow loris bit­ing a human re­sulted in an adult woman en­ter­ing ana­phy­lac­tic shock. (Flea­gle, 1999; Har­ri­son, 1955; Kalimul­lah, et al., 2008; Ravosa, 1998; Stre­icher, 2004)

• Other Physical Features
• endothermic
• bilateral symmetry
• venomous

• Sexual Dimorphism
• male larger

• Range mass

  120 to 500+ g

  4.23 to oz

• Average mass

  400 g

  14.10 oz

• Range length

  15 to 25 cm

  5.91 to 9.84 in

Re­pro­duc­tion

Al­though mat­ing has been ob­served in cap­tiv­ity, lit­tle to noth­ing is known about mat­ing of pygmy slow lorises in the wild.

Fe­male pygmy slow lorises enter es­trus be­tween July and Oc­to­ber. Dur­ing this pe­riod, the fe­male vagina and male testes be­come en­larged. Be­hav­ior also dif­fers dur­ing this pe­riod; fe­males are more likely to ap­proach oth­ers and en­gage in lung­ing, while males are more likely to sniff and lick a fe­male's gen­i­tals and mount them.

Pygmy slow lorises are polyg­y­nous. A male's ter­ri­tory typ­i­cally in­cludes sev­eral fe­males with whom he mates. Males and fe­males com­mu­ni­cate with one an­other through whis­tles. Ol­fac­tory cues are also used to find mates. Males spread their scent through uri­na­tion, and males thus pro­duce more urine than fe­males. Males that spread their scent over a large area have a com­pet­i­tive ad­van­tage, be­cause mark­ing ter­ri­tory is an in­di­ca­tion of health, per­sis­tence, and en­ergy. Fe­males pre­fer males with a fa­mil­iar odor to males they have not pre­vi­ously en­coun­tered, which may be re­lated to in­fre­quent con­tact be­tween the sexes. (Fisher, et al., 2003; Fitch-Sny­der, et al., 1999; Stre­icher, 2004)

• Mating System
• polygynous

Pygmy slow lorises re­pro­duce once every 12 to 18 months. Fe­males enter es­trus be­tween July and Oc­to­ber. After about 6 months, fe­males give birth to 1 to 2 off­spring, gen­er­ally dur­ing the win­ter months. Twin­ning is com­mon among this species. Birthing oc­curs in the open, and in­fants are born fully formed with fur and open eyes. Off­spring are nursed for an av­er­age of 4.5 months, though in some cases wean­ing may take as long as 8 months. Fe­males reach sex­ual ma­tu­rity at about 9 months of age, while males reach sex­ual ma­tu­rity at 18 to 20 months of age. ("Loris, Lesser Slow", 2011; "Pygmy Slow Loris", 2011; Ni­j­man and Nekaris, 2010; Rata­jszczak, 1998; Stre­icher, 2004)

• Key Reproductive Features
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• viviparous

• Breeding interval

  Pygmy slow lorises breed once every 12 to 18 months.

• Breeding season

  Pygmy slow lorises generally breed from end of July to the beginning of October.

• Range number of offspring

  1 to 2

• Average number of offspring

  2

  AnAge

• Average gestation period

  6 months

• Average gestation period

  188 days

  AnAge

• Range weaning age

  4 to 8 months

• Average weaning age

  4.5 months

• Average age at sexual or reproductive maturity (female)

  9 months

• Average age at sexual or reproductive maturity (female)
  Sex: female

  273 days

  AnAge

• Range age at sexual or reproductive maturity (male)

  18 to 20 months

Im­me­di­ately after birth, pygmy slow lorises cling to their mother's un­der­side. Later, moth­ers ex­hibit "park­ing" be­hav­ior, leav­ing their in­fants in a safe lo­ca­tion while they leave to for­age for food. With­out the bur­den of a de­pen­dent, moth­ers can more ef­fi­ciently gather food for them­selves and their off­spring.

In­di­vid­u­als in the San Diego Zoo have a si­m­il­iar par­ent­ing style to that of other species of slow lorises. How­ever, pygmy slow lorises spend more time in close prox­im­ity to their young, tend­ing to hud­dle, sit or stand within 0.3 m of their off­spring more than other species. Moth­ers and in­fants pri­mar­ily es­tab­lish close­ness through pas­sive ven­tral con­tact. Al­though moth­ers do not ap­pear to di­rectly de­fend their young, they tol­er­ate the fol­low­ing be­hav­ior of their young as they get older. As in­fants age, they en­gage more often in adult so­cial be­hav­iors such as groom­ing and play, and less often in hud­dling and ven­tral con­tact. ("Pygmy Slow Loris", 2011; Fitch-Sny­der and Ehrlich, 2003)

• Parental Investment
• female parental care
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female

Lifes­pan/Longevity

In cap­tiv­ity, pygmy slow lorises are ca­pa­ble of re­pro­duc­tion as old as 14 years of age. They have been known to live 20 years in cap­tiv­ity. ("Pygmy Slow Loris", 2011; Rata­jszczak, 1998)

• Range lifespan
  Status: captivity

  20 (high) years

• Average lifespan
  Status: captivity

  17.1 years

  AnAge

Be­hav­ior

Pygmy slow lorises are noc­tur­nal, ar­bo­real quadrupeds with grasp­ing hands and feet. They walk along branches hand over foot, stretch­ing from one branch to the next. Their strong grip al­lows them to hang by their feet and gather food with both hands or to stand bipedally then throw their upper body for­ward to pounce on prey. Pygmy slow lorises al­most ex­clu­sively re­main in trees, ex­cept on rare oc­ca­sions in re­sponse to po­ten­tial preda­tors.

Pygmy slow lorises are thought to move al­most con­stantly dur­ing the night hours of warmer months. Mem­bers of this species are com­monly re­ferred to as "slow lorises" due to the speed of their move­ment, but ob­ser­va­tions made at the Duke Lemur Cen­ter in­di­cate that their move­ment is ac­tu­ally faster than other species of slow loris.

Dur­ing cold win­ter months, pygmy slow lorises are ca­pa­ble of en­ter­ing a state of tor­por and liv­ing off their fat re­serves. They re­duce their ac­tiv­ity, lower their meta­bolic rate and body tem­per­a­ture, and do not for­age. This hi­ber­na­tion-like be­hav­ior is ob­served both in the wild and in cap­tiv­ity.

Be­cause pygmy slow lorises have only rarely been stud­ied in the wild, many as­pects of their be­hav­ior are still un­known. While they are gen­er­ally con­sid­ered soli­tary, pygmy slow lorises are oc­ca­sion­ally char­ac­ter­ized as "gre­gar­i­ous" due to their mat­ing be­hav­ior. A species that spends over 50% of its time with con­specifics is clas­si­fied as gre­gar­i­ous. How­ever, cur­rently no sci­en­tific study has con­firmed this po­ten­tially gre­gar­i­ous na­ture. The ter­ri­tory of one male often over­laps with the ter­ri­tory of sev­eral fe­males, lead­ing to polyg­y­nous mat­ing be­hav­ior and more fre­quent so­cial be­hav­ior in males.

Stud­ies of Sunda slow lorises, a closely re­lated species, sug­gest slow lorises main­tain friendly re­la­tion­ships with con­specifics that share their home range, form­ing "spa­tial groups." It is un­clear how they might ben­e­fit from these so­cial group­ings, as slow lorises rely on cryp­sis for pro­tec­tion from preda­tors, do not as­sist oth­ers in find­ing food, and do not en­gage in al­lo­par­ent­ing. ("Nyc­tice­bus pyg­maeus Bon­hote, 1907", 2011; "Pygmy Slow Loris", 2011; Nekaris, et al., 2008; Rata­jszczak, 1998; Wiens and Zitz­mann, 2003)

• Key Behaviors
• arboreal
• nocturnal
• motile
• hibernation
• solitary
• territorial

Home Range

The home range of pygmy slow lorises is as yet un­known.

In Sunda slow lorises, type of habi­tat af­fects the size of a home range, which is highly vari­able. There is broad over­lap be­tween ranges of Sunda slow lorises. (Wiens and Zitz­mann, 2003)

Com­mu­ni­ca­tion and Per­cep­tion

Pygmy slow lorises uti­lize a va­ri­ety of ver­bal com­mu­ni­ca­tions. When dis­turbed, they growl and hiss. They issue a ris­ing tone dur­ing gen­eral con­tact and may whis­tle to the op­po­site sex dur­ing es­trus. Moth­ers softly chirp to their in­fants, who re­spond with rapid clicks and squeaks when they are in dis­tress.

Males mark their ter­ri­tory with urine, which also af­fects mat­ing be­hav­ior (See Re­pro­duc­tion: Mat­ing Sys­tems). ("Loris, Lesser Slow", 2011; Fisher, et al., 2003)

• Communication Channels
• acoustic
• chemical

• Other Communication Modes
• scent marks

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Re­ports from local peo­ple of Cam­bo­dia sug­gest pygmy slow lorises eat mostly ter­mites, tree parts, fruit, and bam­boo. Though sur­veys con­firm they do eat this va­ri­ety of foods, the ab­solute pref­er­ence for ter­mites over the other foods is not clear. There is also great de­bate over the de­gree of in­sec­tivory in this species. Some sug­gest that in­sects make up ap­prox­i­mately 33% of their diet (Duke Lemur Cen­ter 2011), while oth­ers state that they are fru­giv­o­rous (Flea­gle 1999). Al­though early ac­counts of the species (Har­ri­son 1955) in­di­cate that mem­bers of this species eat in­sects, lizards, eggs, and "any­thing ed­i­ble" in ad­di­tion to fruit, re­cent stud­ies do not cor­rob­o­rate these ob­ser­va­tions.

At the En­dan­gered Pri­mate Res­cue Cen­ter, cap­tive pygmy slow lorises are of­fered fruit, veg­eta­bles, boiled eggs, milk pow­der, and in­sects, and the in­sects are the most read­ily ac­cepted food item. How­ever, this find­ing can­not be used to as­sert they are not fru­giv­o­rous, be­cause the cul­ti­vated fruit of­fered to them may not be what they pre­fer in the wild.

Cap­tive an­i­mals also gouge fresh tree branches, in­di­cat­ing a pref­er­ence for ex­u­dates. They have been ob­served lick­ing Saraca dives, Sapin­dus and Ver­ni­cia mon­tana trees for pe­ri­ods be­tween 1 and 20 min­utes. Pygmy slow loris scratch and break the bark of other species of trees, feed­ing on the gum.

Pygmy slow lorises de­velop fat stores by in­creas­ing their feed­ing and choos­ing more en­ergy-rich foods in the last few weeks of au­tumn. These fat stores are use­ful dur­ing the food scarce win­ter months.

De­spite the high-sugar diet and small body mass of close rel­a­tives Sunda slow lorises, they have a very low me­tab­o­lism. This may be due to a need to detox­ify the toxic sec­ondary com­pounds in their food mat­ter. ("Pygmy Slow Loris", 2011; Flea­gle, 1999; Har­ri­son, 1955; Rata­jszczak, 1998; Starr, et al., 2011; Stre­icher, 2004; Wiens, et al., 2006)

• Primary Diet
• carnivore
  • insectivore
• herbivore
  • frugivore
• omnivore

• Animal Foods
• eggs
• insects

• Plant Foods
• fruit
• nectar
• flowers
• sap or other plant fluids

• Other Foods
• fungus

Pre­da­tion

Lit­tle is known re­gard­ing non-hu­man pre­da­tion of pygmy slow lorises. Al­though pre­da­tion by Suma­tran orang­utans has been re­ported, the habi­tats of Suma­tran orang­utans and pygmy slow lorises do not over­lap. Pre­da­tion by retic­u­lated pythons has also been re­ported. Pygmy slow lorises are cryp­tic, blend­ing in well with their sur­round­ings. This may con­tribute to low non-hu­man pre­da­tion rates.

Hu­mans are the pri­mary preda­tors of pygmy slow lorises. Their preva­lence in Cam­bo­dian and Viet­namese mar­kets tes­ti­fies to the in­tense hunt­ing pres­sure on this species. Camo­bo­dian lo­cals re­port hunt­ing pygmy slow loris as a "non-tar­get species," sug­gest­ing that the rate of hunt­ing is not af­fected by abun­dance and will con­tinue even as these an­i­mals be­come more scarce.

Pygmy slow lorises are easy prey be­cause of their tape­tum lu­cidum, the re­flec­tive layer in the eye that im­proves night vi­sion, which glows when a spot­light is shone in their di­rec­tion and by some ac­counts in­ca­pac­i­tates them. This makes this species an easy tar­get for night hunters. (Starr, et al., 2011; Stre­icher, 2004; Wiens and Zitz­mann, 1999)

• Anti-predator Adaptations
• cryptic

• Known Predators

  • humans Homo sapiens
  • reticulated pythons Python reticulatus

Ecosys­tem Roles

Be­cause they may con­sume a con­sid­er­able amount of fruit, pygmy slow lorises may play a role in seed dis­per­sal.

In Pol­ish zoos, oocytes of the par­a­sitic pro­to­zoan Cryp­tosporid­ium, "crypto", have been found in the feces of pygmy slow lorises, in­di­cat­ing in­fec­tion. Crypto is not typ­i­cally stud­ied in non-do­mes­ti­cated non-hu­man pri­mates, and lit­tle in­for­ma­tion is avail­able re­gard­ing its preva­lence.

An out­break of oc­u­lar oxyspiruro­sis in a Moscow zoo was at­trib­uted to a pygmy slow loris from Viet­nam. This con­di­tion is caused by the par­a­sitic ne­ma­tode Oxyspirura.

Pygmy slow lorises also act as hosts to some pro­to­zoan par­a­sites (En­ta­moeba his­toyt­ica, Blan­tid­ium coli, Tox­o­plasma gondii, Gi­a­r­dia, Blas­to­cys­tis ho­minis) and ne­ma­todes (En­ter­o­bius, Oxyrus, Trichuris). (Fayer and Xiao, 2008; Ivanova, et al., 2007; Schulze, 2005)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Pygmy slow lorises are com­monly used in med­i­cines in Cam­bo­dia. In Phnom Penh, they are found in local mar­kets roasted, dried, and made into pre-mixed med­i­cines with rice-wine, al­co­hol, honey, or char­coal. Doc­tors of tra­di­tional med­i­cine re­ported in ques­tion­naires that these med­i­cines are pri­mar­ily used to treat "women after child­birth, stom­ach prob­lems, wounds, bro­ken bones, and sex­u­ally trans­mit­ted dis­eases" (Starr et al. 2010). In the 1950s from Burma to Bor­neo, the fur of slow lorises was used to dress wounds and cuts be­cause of its blood clot­ting prop­er­ties, and it may still be used as such in some lo­cal­i­ties. Some re­searchers at­tribute the pop­u­lar­ity of loris med­i­cine to the lack of ac­cess to or ed­u­ca­tion about bio­med­ical al­ter­na­tives and high lev­els of poverty.

Due to in­creased pro­tec­tion of this species, mar­ket price is in­creas­ing. Vet­eran hunters able to dis­tin­guish dif­fer­ent species of loris and know species dis­tri­b­u­tions in local forests yield high prof­its. Trade is dri­ven by wealthy city dwellers who are able and will­ing to pay rural hunters for their il­le­gal prod­uct.

Live trade of slow lorises oc­curs in high lev­els in the Mon­dulkiri, Ratanakiri, and Phnom Penh provinces of Cam­bo­dia. As many as 204 lorises were found in a sin­gle store in Phnom Penh. Slow lorises are the most pop­u­lar pets that are listed on CITES Ap­pen­dix I. They are pri­mar­ily traded in Bor­neo, Java, Suma­tra, and the sur­round­ing is­lands. Live trade of slow lorises most com­monly af­fects Sunda slow lorises, Bornean slow lorises, and Javan slow lorises, but traders do not dis­tin­guish among species, and other slow lorises such as pygmy slow lorises are some­times traded as well. This lack of dif­fer­en­ti­a­tion among species leads to hy­bridiza­tion, im­proper care and health prob­lems, as well as rein­tro­duc­tion of con­fis­cated an­i­mals into im­proper habi­tat. (Das­gupta, et al., 2005; Har­ri­son, 1955; Nekaris and Jaffe, 2007; Nekaris, et al., 2010; Starr, et al., 2010)

• Positive Impacts
• pet trade
• source of medicine or drug

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Pygmy slow lorises may pro­duce a toxin from mod­i­fied sweat glands lo­cated near their el­bows. They have a toxic bite which is dan­ger­ous to hu­mans. The only ac­count of a pygmy slow loris bit­ing a human re­sulted in the adult woman en­ter­ing ana­phy­lac­tic shock. (Wiens, et al., 2006)

• Negative Impacts
• injures humans
  • bites or stings
  • poisonous

Con­ser­va­tion Sta­tus

Pygmy slow lorises are con­sid­ered threat­ened by the IUCN. Pop­u­la­tions de­creased by 30% be­tween 1984 and 2008, and they con­tinue to de­cline.

Pop­u­la­tions of pygmy slow lorises dras­ti­cally de­clined dur­ing the Viet­nam War, as bomb­ing, land clear­ing by Rome plows, and use of Agent Or­ange (2,4,5-T), other de­fo­liants, and na­palm de­stroyed the ma­jor­ity of their na­tive habi­tat in Viet­nam, Laos, and Cam­bo­dia. Bomb­ing is es­ti­mated to have dam­aged 40% of Viet­namese forests, and her­bi­cides af­fected 43% of the cul­ti­vated area. Prior to the Viet­nam War, broad-leafed trop­i­cal forests with stands of bam­boo and man­groves cov­ered ap­prox­i­mately one-half of the land area in these coun­tries.

The use of pygmy slow lorises in tra­di­tional med­i­cine, as well as the re­luc­tance of con­sumers and doc­tors of tra­di­tional med­i­cine to use al­ter­na­tives, threat­ens the fu­ture of this species.

Lorises are fre­quently killed by log­ging and slash and burn agri­cul­ture. If they are not killed in the fire, they face habi­tat de­struc­tion, which may lead to their even­tual dis­ap­pear­ance from the area. The re­sult­ing frag­men­ta­tion of forests fur­ther threat­ens the species.

Pygmy slow lorises were listed in Ap­pen­dix II by the Con­ven­tion on In­ter­na­tional Trade in En­dan­gered Species of Wild Fauna and Flora (CITES) in Feb­ru­ary 1977. They were pro­moted to Ap­pen­dix I in Sep­tem­ber 2007, which in­di­cates trade of this species has not been prop­erly con­trolled in the last few decades.

Al­though trade is re­stricted and cap­ture and trans­port of pygmy slow lorises is il­le­gal in all coun­tries in their range, their small size makes slow lorises easy to traf­fic in boxes, bas­kets, and sacks from coun­try to coun­try. This process is phys­i­cally stress­ful for the an­i­mals and also threat­ens their health. Res­cue cen­ters have been de­vel­oped for con­fis­cated slow lorises, but mor­tal­ity rates re­main high. These deaths are at­trib­uted to trauma, dis­ease, and atyp­i­cally close prox­im­ity to con­specifics. (Rata­jszczak, 1998; Starr, et al., 2010; Stre­icher, et al., 2008; Stre­icher, 2004; "UNEP-WCMC Species Data­base: CITES-Listed Species", 2011)

• IUCN Red List

  Vulnerable
  More information

• IUCN Red List

  Vulnerable
  More information

• US Federal List

  Threatened

• CITES

  Appendix I

Other Com­ments

In Viet­namese folk­lore, pygmy slow lorises are called "khi gio", or "mon­keys that move with the wind." They por­tend bad for­tune and are used for black magic. (Stre­icher, 2004)

Con­trib­u­tors

Mar­garet Gray (au­thor), Yale Uni­ver­sity, Eric Sar­gis (ed­i­tor), Yale Uni­ver­sity, Gail Mc­Cormick (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Ref­er­ences

2011. "Loris, Lesser Slow" (On-line). Cleve­land Metroparks Zoo. Ac­cessed April 27, 2011 at http://​www.​clemetzoo.​com/​animals/?​action=details&​animals_​id=1066.

2011. "Nyc­tice­bus pyg­maeus Bon­hote, 1907" (On-line). En­cy­clo­pe­dia of Life. Ac­cessed April 27, 2011 at http://​www.​eol.​org/​pages/​326539.

Duke Lemur Cen­ter. 2011. "Pygmy Slow Loris" (On-line). Duke Lemur Cen­ter: Study­ing and Car­ing for Lemurs. Ac­cessed April 26, 2011 at http://​lemur.​duke.​edu/​category/​nocturnal-lemurs/​pygmy-slow-loris/​.

UNEP-WCMC. 2011. "UNEP-WCMC Species Data­base: CITES-Listed Species" (On-line). Ac­cessed April 26, 2011 at http://​www.​unep-wcmc-apps.​org/​isdb/​CITES/​Taxonomy/​tax-species-result.​cfm/​isdb/​CITES/​Taxonomy/​tax-species-result.​cfm?​Genus=Nycticebus&​Species=pygmaeus&​source=animals&​tabname=legal.

1993. "Viet­nam: War and the En­vi­ron­ment" (On-line). Green Left. Ac­cessed April 27, 2011 at http://​www.​greenleft.​org.​au/​node/​6044.

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