Tent-making Bats

Tent-making bats are relatively common in Costa Rica, and there are 15 species here.  Once you know what you are looking for, the bent leaves stand out like beacons in the rainforest where these animals are roosting. The bats roost underneath several of the broad leafed plant species, and seem to favour fan palms and heliconia leaves. They chew the across the underside of the leaves to cause them to hang down at the sides in order to create a protective canopy. A group of these bats will contain a single male and a harem of females. These intriguing little bats are frugivores, and feed on a variety of rainforest fruits.  

These bats are roosting only metres from our front door.  This is possibly Uroderma  sp. , however many of the tent-makers in Costa Rica look superficially alike. 

These two are cooperating for the camera, however, it is difficult to sneak under the tent without  scaring them away. They have large eyes and relatively good eyesight.

Costa Rica - A mixed bag

This post is a bit of everything - no particular theme just various species we have encountered and photographed over the last couple of weeks.

An adult male Basilisk (Basiliscus basiliscus).  These lizards can run across the surface of water on their hind legs. We see them do this across our local river, the Rio Tigre.  This is incredible to witness.

A Costa Rican huntsman, possibly from the genus Olios. We have recently observed two leaf-nests of juveniles (up to 4th instar)  residing together without an adult present. They were clearly foraging around the nest and a number of individuals returned to the nest once they were disturbed. This is very unusual behaviour for this group of spiders.

A cicada. One of several large species that we have seen on the Osa .

A predatory 'orange-faced katydid'. We have yet to identify this species.

A very large and spectacular reduviid. This assassin bug seems to specialise upon hymenopteran prey. We found one feeding on a wasp twice its size. This individual is feeding on a Golden carpenter ant (Camponotus sericeiventris). This is another species we have not been able to identify. Too many invertebrates, too little information!

Golden carpenter ant (Camponotus sericeiventris)

A juvenile Terciopelo or Fer-de-lance (Bothrops asper), Costa Rica's most feared snake. I have found eight of them so far - they are very common in this region.  Despite their reputation for aggression, most of the individuals have been quite tolerant of our presence, and timid rather than agressive.

The same  juvenile Terciopelo. Juveniles will often sit up a metre or so off the ground. This one was perched on a pineapple plant about a metre off the ground.

A large ant which the locals call a 'bala' ant due to the bullet like nature of the sting - most likely in the genus Dinoponera. The true bala ant (Paraponera clavata) reputedly has the most painful sting of all ants. It is found on the Caribbean side of Costa Rica.  

A Blunt-headed tree snake (Imantodes cenchoa)

Disc-winged bats (Thyroptera tricolor) within an unfurled Helconia leaf. This species lives in small groups and  moves to a new roosting site every night. This is because they growing leaves unfurl so quickly that within 24 hours they are no longer suitable. They use the suction discs to grip onto the leaves - you can see a number of the bats' discs in this image.

A close-up of the disc on the wing of Thyroptera tricolor. This one gripped onto my finger nail and had incredible holding power.

A iridescent Euglossine bee (orchid bee)
 bee visiting a flower.

A black and white Carabid beetle, a scavenger found on leaves at night.

Wet forest toad (Bufo melanochloris). We have many Giant (Cane) toads here too. It is a bit strange coming  from north Queensland to Costa Rica and seeing Cane toads in their native habitat.

Wet forest toad (Bufo melanochloris)

A close-up of Bufo melanochloris

Another Poison Dart Frog

Dendrobates auratus is known as the Green and Black Poison Dart Frog for obvious reasons, however, colours do vary throughout their range the extreme being blue and black.

This is the second Dendrobates species we have found close to where we are living. Like the other species we have encountered (Dendrobates granuliferus), D. auratus is most active in the early mornings. They are extremely lively little frogs, continually hopping in short sharp leaps, rarely pausing for too long. Makes for a challenging photographic subject.

Costa Rica – Lizards around the house

We are fortunate to have numerous species of lizards all around us, so do not have to go far to see them. Most of the lizards in this post can be observed from our front veranda.

The Basilisk (Basiliscus basiliscus) is a species renowned for its ability to run on water. Juveniles are very common in this area, but the adults tend to spend most of their time near the river and are harder to get close to. During the day these lizards are active hunters, and move extremely rapidly to capture prey such as invertebrates and smaller lizards. At night however, they perch on foliage to sleep and we have found many of them hanging quite oblivious to approach on foliage around the yard and in the forest areas.

A young Basilisk, perched upon  a flower.

Another juvenile Basilisk

An adult male Basilisk

Common Anoles (Norops polylepis), true to their name are very abundant here. We were very excited to find a less common Green Tree Anole (Norops biporcatus) on the property. Anoles are well known for the territorial displays performed by males. They flash a colourful flap of skin beneath their throat known as a dewlap to warn off rival males.

A Common Anole with its dewlap exposed

The Green Tree Anole

Green Tree Anole

A close-up of the Green Tree Anole

We also have found Green Iguanas (Iguana iguana) right here on the property. The juveniles are a brilliant green, but lose the colour as they mature. The larger adults are grey-brown in colour and truly prehistoric in appearance. Green Iguanas are vegetarians and feed on the foliage of a variety of trees and shrubs, and will also feed on fruit. We spotted nine juveniles sleeping on one bush recently while were looking for invertebrates at night.

A juvenile Green Iguana

The head of a juvenile Green Iguana

One species which is found deeper in the rainforest is the Helmeted Iguana (Corytophanes cristatus), a species which can change its colour rapidly. I have been lucky enough to find two of these lizards while on our invertebrate collecting walks. These secretive lizards are ambush hunters and feed on a wide range of invertebrates. They apparently will also feed on Anole lizards.

A Helmeted Iguana

Helmeted Iguana

Costa Rica – Poison-dart frog

This spectacular little frog is the Granular Poison-dart Frog (Dendrobates granuliferus). Deanna found this gem on a rainforest trail during our nightly invertebrate collection walks.

Although this individual turned up at night, this species is primarily diurnal. The buzzing calls of the males can be heard from dawn until mid-morning.  They will also call late in the afternoon but fall silent when the bulk of the frogs here begin their activity after dark.

These frogs have potent toxins within their skin, an obvious strategy to avoid predation. Their common name is derived from its use by native hunters; they would extract the toxins and cover the tips of their darts, thus killing prey quickly with a small projectile. The species with the most potent toxin occurs in Columbia, where this practice was common.

Dendrobates granuliferus lays it eggs on the forest floor. After the tadpoles emerge, the adults carry them individually up into the trees and deposit them into small bodies of water, such as that held in bromeliads. 

Costa Rica - Week 3 Moss Mantis

One of most amazing invertebrate encounters so far is the discovery of this ‘moss mantis’. We were looking for mantids in a patch of primary rainforest, but I didn’t expect to spot something as bizarre as this. I noticed a piece of moss hanging below a branch about five metre off the side of the trail we were on, but something struck me about its shape. When I stepped closer I thought I could make out a leg, then another, and once I spotted the antennae I knew I was looking at something pretty cool.

The 'moss mantis'. One of the most amazing mantids I have ever seen.

We haven’t identified this species yet, but it is truly a master of camouflage. It has the combined features and colours of moss and lichens which serve to hide its body form, and the result is stunning. I am quite amazed that I spotted it, even with years of experience in looking for such things.

This species is covered in bumps and flanges which  look incredibly like lichens and mosses.

Being a mantis it is naturally a predator, and one with complete ambush on its side. When it moves it rocks from side to side in very pronounced manner, just like the mossy tendrils hanging below the branches in its habitat. This enables it to move from one place to another without attracting the attention of predatory birds, lizards and frogs.

Even the eyes are superbly disguised.

Costa Rica - Week 3 Boa Constrictor

We've been hoping to see a Boa, but didn’t quite expect to see one turn up in town. The young Boa pictured below fell out from beneath a car at the local service station as the car pulled away. It must have hitched a ride from somewhere and decided that was far enough.

The lucky young Boa Constrictor after its release in our backyard.

Our local assistant Steve was waiting for fuel and saw the snake appear, a lucky thing for the snake as the attendants were apparently a little fearful of it at first. I was waiting for Steve in the hardware store, and when he brought it in to me I was quite impressed with his bonus find at the gas station. If only Australian service stations would offer free reptiles with every 20 litres of fuel.

I took the snake back out to our rainforest abode, and released it after we’d all had a good look at it and taken a few pics.

It found a nice secure spot to spend the remainder of the day. 

Boa constrictors are the largest and heaviest snakes in Costa Rica. Although they have been recorded at growing to 5.5m, the largest specimens usually found are around 3.5m long. Boas are very robust snakes, so a specimen over three metres is a significant predator. Like pythons, they can feed on animals much larger than their head size. Costa Rican Boas feed on iguanas and other lizards, mammals including monkeys, and even deer.