Bulletin of the EANHS 27(2/3) 
28 
apparent either through a hand lens, or as the larvae 
grow. The banding is in the body colour, whereas the 
hairs are all dart: brown. Desmond! caterpillars are very 
dark brown — but with a white (slightly bluish) patch at 
the head and tail ends. The two species cannot be 
confused. Moreover, the desmondi caterpillars, at this 
stage and unlike n Ire us. prefer to be under the leaf rather 
than on the upper side. It is not until sometime during 
the second instar that desmondi moves to the upper 
leaf surface — so the lower surface of leaves should 
always be searched, for larvae as much as for eggs. The 
second 'stage' still has the light segments at head and 
tail, but like nireus. now has some orangish colour on 
some of the middle segments. The third stage' has a 
much more ashy and dull green colour, unlike the leaf- 
green colour of nireus. The final stage is uniform 
greenish all over— whereas nireus has a lighter shade 
of green between the 'V* pattern in the middle of the 
body segments. The desmondi final stage, also often 
has a very marked blue colour to the intersegmenta! 
memhranes and. even in earlier stages, small paired 
appendoges at head and tail end tend to be slightly 
bluish— rather than the whitisli/yellowisli version in 
nireus. And so to the pupa, which w ould be difficult to 
distinguish from the green form of nireus. 1 never found 
any brown pupae. The whole process as far as pupation, 
took from 38—18 days, depending on temperature and 
feeding conditions; aqd from 1 8-25 days for the pupal 
stage (not much different from nireus). In both species, 
the males are easily distinguished by the whitish line 
on the underside of the hind- wing and b> a generally 
darker background colour. On the upper surface, the 
desmondi are best distinguished in that the blue stripe 
on the front wing is not only wider (especially in (he 
males) but is also narrower towards the from, whereas 
in nireus the blue stripe has parallel sides Tlicre is some 
variation in the width of blue in both species although 
the average desmondi width is typically twice as wide 
as nireus. You are more likely to be confused by the 
females in tills regard than the males. 
Seasonal Variations 
The maximum rate of discovery was in June— a time 
when the presence of nireus is starting to decline w ith 
the colder weather. However, the sample sizes were very 
small, the June maximum for desmondi resulting from 
the discovery of three eggs— although in more than 
one area After that, there was a decline in desmondi 
numbers— but not as steeply as for nireus. Only in 
November and December were no eggs found None of 
the larvae showed any tendency to hibernate as nireux 
docs. The result is that, although desmondi is Affected 
by the weather, it is more of an 'all year-round* butterfly 
than nireus-, and this is bom out by observations of the 
adults. With this in mind, it is not surprising that there 
arc even times when desmondi is more numerous (in 
the right son of forest area) than nireus— ns well as the 
reverse. I never had any that were parasitised by the 
Different preferences for laying eggs 
It had been an early observation that the desmondi 
larvae discovered were always in shady areas of 
Toddalia. They were never discovered along paths 
which were effectively in the open, whereas nireus were 
commoner in open places. This may explain why 
desmondi is dependant on there being 'forest' nearby 
for it to breed successfully. 
And do they lay eggs on other plants too? In the 
only experiment I did, fltree newly hatched larvae each 
were put on leaves of C irrus, Clausena and TecJeo — as 
well as Toddalia Possibly, there was a linic growth on 
one specimen on Clausena, but even that one. as well 
as all the others, were dead within 6 days, Ifnot earlier. 
In the same, time, the 5 larvae on Toddalia had more 
than doubled their size. One example is insufficient 
proof— although an earlier larva, just hatched, was lost 
through ils 'walking ofT Clausena — which nireus 
would not have done. It has been reported that there 
are populations thriving on Citrus in the Mbololo area 
(Wild-Life Clubs— Mike Clifton). Obviously this is 
possible and to be welcomed; but m present. I would 
guess from the above that the majority- of desmondi are 
stiU breeding on Toddalia. No other host plant is common 
enough in Toito. to support the existing numbers of 
desmondi. The Taita Hills survey (Nairobi Museum) had 
found that Toddalia is common or occasional in many 
forests — especially at the edges; whereas Vespris was 
only on Ngangao (and Sagalla), and Teclea mostly at 
Ngangao (although there was some T nobilis at 
Mbololo) So. although van Somercn (date) reports ‘P. 
teitu' on Teclea and Vespris, I wonder whether these 
are die main food plant! — at least today. 
Future 
Its future is probably safe! In places. Toddalia is 
abundant, and being tough, it grows again quickly 
whenever cut back. The fact that the host plant is 
growing under exotic trees, as opposed to natural forest, 
is no deterrent to P. desmondi ; indeed, it may have even 
expanded its numbers in that cutting down older forests 
has actually increased the amounts of Todduliu\ Not 
only Ls it present in places like Mbololo and Mwwnbirwa 
and Ngangoo. but we hove seen it at Choke— a relatively 
small piece of forest The earlier report by ICBP, had 
guessed that there could be scattered small populations 
of desmondi and that guess seems correct. I have also 
seen an individual male at Shtgharo. and another at 
Wesu; and that points probably to other centres— 
Toddalia being present in both of those places. It is 
pretty safe as a species for some time: indeed, it could 
be common and secure enough to become a lest case 
for butterfly farming It could give a chance to make 
some income from the maJ es. and to help keep the stocks 
ol wild females higher too. Of course more research is 
needed — for example, as !o the optimum conditions for 
wasps that affected nireus caterpillars, but my sample 
sizes were small. 
getting this delicate and more shade-loving species to 
lay eggs. But it is a colourful species worth conserving; 
and in so doing, the local people could be helped to 
