Sustainable Development and Wild Nature Conservation in NICARAGUA
Laguna de Apoyo, Nicaragua, is an extremely important site for students of cichlid evolution. In 1976, the US biologist George
Barlow and his student, John Munsey, recognized a body-shape dimorphism among the Midas cichlids in the lake. The more typical, deeper-bodied Midas
cichlid form found in Lake Apoyo corresponded approximately with the majority of the Midas cichlids found
throughout the range. But in Laguna de Apoyo, an elongate form
contrasting with the more common, deeper-bodied fishes, became the subject of study of the scientists, who described the elongate form as a distinct
which they termed the arrow cichlid, in 1976.
Although the idea that the
Midas cichlids constituted many species had been proposed more than a century earlier, an alternative hypothesis for the great variety in
this group was simply that it was a highly variable species. The dimorphism in body length between Amphilophus zaliosus and the
other, deeper-bodied Midas cichlids in Lake Apoyo, demonstrated by Barlow and Munsey, was convincing. Furthermore, the idea that the Midas cichlids
constitute a species complex fortified the idea that thick-lipped varieties may also constitute distinct species (today classified as
The arrow cichlid may be found in older literature as Cichlasoma zaliosum, which is now classified as a junior
synonym. Its common name in Nicaragua is mojarra flecha.
Breeding coloration in Amphilophus zaliosus is velvety black. Photo Ad Konings.
The arrow cichlid not only differs from other members of the Midas cichlid species complex in Laguna de Apoyo by its
elongate body form. It is also distinctly silver when not in breeding coloration, lacking the yellowish background of some of the other Midas
cichlid forms in the
lake. The series of spots along its side, characteristic of the Midas cichlids, appear box-like and may practically form a lateral stripe over
the grey background. When in courtship or reproduction, the fish may become velvety black, as the black vertical bars typical of the
breeding Midas cichlids may completely merge laterally.
Two arrow cichlids on their way to a museum. Specimens such as these are vital for the identification of new species of fishes in the Midas
cichlid species complex. Photo Matthias Geiger.
The internationally recognized classification of endangered species, the IUCN Red List, classifies the arrow cichlid as
Critically Endangered. The range of Amphilophus zaliosus is
limited to Laguna de Apoyo. Other, similarly elongate forms have been found, such as Amphilophus
sagittae in Laguna de Xiloá, but recent genetic research has demonstrated conclusively that the arrow cichlid is closely related to, and presumably
evolved from, other forms found in Laguna de Apoyo.
A breeding pair of arrow cichlids with fry in open water, over an algae mat in Laguna de Apoyo. Click on the photo to see the pair
in action in video. Photo Garey Knop.
An arrow cichlid Amphilophus zaliosus among fry in Laguna de Apoyo. Photo
This subadult arrow cichlid is presenting the typical coloration of nonbreeding
adults, with black spots laterally over a silvery base color. Photo Ad Konings.
Arrow cichlids defending fry. Photo Garey Knop.
Would you like to share your photographs of the arrow cichlid and other great underwater fun in Laguna de Apoyo Nature
Reserve? Please share them with us by contacting us.
The arrow cichlid is easily seen in Lake Apoyo when SCUBA diving in appropriate locations.
Certified open-water divers can join us in studies of the arrow cichlid and other aquatic fauna of Laguna de Apoyo. Please
contact us if you would like to dive with our scientists.
You can help us keep nature wild in Nicaragua, by volunteering your time with us or making a small donation to support
our projects in wild nature conservation.
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Amphilophus chancho, one of the fish species endemic to
Laguna de Apoyo, discovered by scientists working in a GAIA project. This species is easily
seen while diving in Laguna de Apoyo. Photo Ad Konings.
This baby squirrel was raised by the staff after she fell from a tree as an infant. Today she has her own family in the trees above Estación Biológica.
Photo Jeffrey McCrary.
Field research is conducted on several animal and plant groups at Estación Biológica Laguna de Apoyo. Photo
Spanish classes for volunteers, interns and other visitos are vital components of our educational program in Laguna de Apoyo Nature Reserve. Photo
Bird populations are monitored in Laguna de Apoyo Nature Reserve by the staff and volunteers of Estación Biológica
Laguna de Apoyo. Photo Joe Taylor.
The forest inside the crater in Laguna de Apoyo Nature Reserve contains dozens of terrestrial species, making the area an
ideal site for wildlife studies. Photo Jeffrey McCrary.
Field identification of the reptiles of Laguna de Apoyo Nature Reserve. Photo Kolby Kirk.
Scientists at Estación Biológica Laguna de Apoyo study endangered fish species in the lake. Certified SCUBA divers can accompany us on research dives
where endemic fish species can be readily seen.
Photo Topi Lehtonen.
Scientists at Estación Biológica Laguna de Apoyo conduct surveys of wildlife, including resident and migratory birds. Photo Wendy van Kooten.
Animal rescue at Estación Biológica Laguna de Apoyo. Here, Gaia Director Jeffrey McCrary is accompanied by
a rapidly healing variegated squirrel that was severely injured by illegal poachers. Photo Anne Sutton.