My thoughts ............... Malayan Pit Viper. Nasty little suckers, no warning just strike. Plentiful everywhere in Thailand. Built up areas don't seem to bother them much ........ even come across them on dark evenings after rain on roads looking for rodents. I've stopped wearing "flip flops" now ........ nearly stepped on one on the darkside in Soi Khaw Noi, only just I saw it in time ......... curled up in an entrance to a beer bar, thought it was dog's poo .... yikes!! Many juveniles around the area too ......... as venomous & deadly from birth ...... about 20cm in length. They don't run, stepping on one ruins your day. Hospital immediately & get treatment ......... loss of limb or possibly worse if you delay. As I've said probably the worst snake around here due to their commonality although there's other varieties that are as dangerous, but not so common. ie Russel Viper, Banded Kraits & Cobra's. 

4 minutes ago, Daveyh said:

My thoughts ............... Malayan Pit Viper. Nasty little suckers, no warning just strike. Plentiful everywhere in Thailand. Built up areas don't seem to bother them much ........ even come across them on dark evenings after rain on roads looking for rodents. I've stopped wearing "flip flops" now ........ nearly stepped on one on the darkside in Soi Khaw Noi, only just I saw it in time ......... curled up in an entrance to a beer bar, thought it was dog's poo .... yikes!! Many juveniles around the area too ......... as venomous & deadly from birth ...... about 20cm in length. They don't run, stepping on one ruins your day. Hospital immediately & get treatment ......... loss of limb or possibly worse if you delay. As I've said probably the worst snake around here due to their commonality although there's other varieties that are as dangerous, but not so common. ie Russel Viper, Banded Kraits & Cobra's. 

I think there are 4 or 5 most common kinds of viper in Thailand, once i had a water viper in my garden pond.

Although i cannot tell the difference, all vipers have a characteristic triangular head, and they are all very venomous.

I don't see a snake around here since 5/6 years, i guess it's the only positive side of the increasing population and road traffic on the island.

Any snake i see i kill ,except for Cobra's keep away from them big,fast and some can spit venom,unless you have a shot gun,used too come up with a lot when we were gold prospecting in New Guinea,one of my co partners in our expeditions Carruthers used get into the most awful funk if he saw one,one night one of our porters caught a non venemous tree snake,he wanted too cook it of course Carruthers had had more than his fair share of brandy,so Snodburry and i threw it in his tent,the screaming and cursing went on until the poor creature slid out of the tent,and was henceforth cooked and eaten,Carruthers refused to talk to us for two days a blessed relief, he then became overwrought by the whole thing one night he wen't beserk yelling and screaming about us ,eventually he kicked the fire almost causing our tents to go up in the resulting confliguration around us,he then emerged from his tent with a rifle,luckily Snodburry was junior boxing champion at Eton when younger,decked him with one punch,led to unpleasant atmosphere for rest of expedition,have too say i didn't give a fig,he only went to a minor public school,where as Snodburry and i where veterans of Eton and Harrow,and on an earlier trip,i had caught him looking at me as i bathed naked in a creek looking at me in a most un-natural manner. Sorry rambling here do hope lady get's better.

When I worked on the Yadana Pipeline for PTT we had a wall chart with 8 venomus snakes native to Thailand, can't remember the names now this was in 1998/99.

The 2 worst were the black and yellow striped, and a small green bamboo viper

A doctor gave us a talk about getting bit, basically don't panic, get to a clinic and if at all possible bring the (now) dead snake that bite you so they would know what type of anti-venom. Each snake has different venom and needs different anti venom.