Holothuria cf. inhabilis (Fig. 8.5g), a remarkable large sized sea cucumber
(about 30 cm in length in life), is frequent on the soft bottoms surrounding rocky
reefs, where it feeds on organic sediments. This species, reported as a possible new
species when it was collected at Islas Lobos de Afuera (Hooker et al. 2005), should
be reevaluated in order to clarify doubts concerning its taxonomy identity.
On shallow sandy bottoms the dominant echinoderms are the seastars Astropecten spp., with A. armatus as the most frequent (Fig. 8.4a). The sand dollar
Encope micropora has also been reported from this habitat, but seems to be more
frequent in the biogeographic transition region. Luidia bellonae is rarely reported
in deeper waters (10–20 m) along the north Peruvian coast. However, it is fairly
common in Islas Lobos de Afuera. There are no records of this species south of
Islas Lobos de Afuera. Nevertheless, Clark (1910), Anonymous (2010) and
Morales-Montecinos (2011) reported it from central and southern Peru. In waters
below 50 m depth, L. superba is the dominant seastar, together with Clypeaster
europacificus. Both species are frequently caught in artisanal fishing nets.
8.3.3 Tumbes Mangroves
Northern Peruvian mangroves possess a typical Tropical Eastern Pacific fauna but
the reported faunal diversity is low. The most representative species is Mellitella
stokesii, a very common sand dollar in sandy tide pools and intertidal beaches in
the interface between the mangroves and the sea (Fig. 8.4d). Another abundant
species is the sea urchin Agassizia scrobiculata. Dense populations occupy the
bottom of tidal creeks at depths between 0.5 and 2 m at low tide. The brittle star
O. magnifica is also frequent, mainly between mangrove roots and inside sponges
and zoanthids. Another ophiuran, an unidentified species of the genus Ophiogrammus, has been recorded in the muddy sand bottoms. A bright-orange morph of
Luidia brevispina is common on sandy beaches around mangroves, different from
the grey specimens known from Lobos de Afuera.
8.3.4 Biogeographic Transition Area Temperate South Eastern
Pacific-Tropical Eastern Pacific
As mentioned earlier, the transition area between these biogeographic provinces is
between Cabo Blanco (4°15
0 S) and Punta Aguja (6°S). This also includes the
islands Lobos de Tierra and Lobos de Afuera. Echinoderms of both provinces are
found in this refuge area as well as clear differences in abundance. For example,
O. magnifica is extremely abundant in almost every habitat, with the exception of
mud and fine sand bottoms. Another abundant species is Neothyone gibber,
especially at Lobos de Tierra where it covers 100 % of the vertical walls of large
rocks (Fig. 8.5e). Intertidal cliffs are dominated by H. helianthus. The sea
8 Echinoderms of Peru
291
(about 30 cm in length in life), is frequent on the soft bottoms surrounding rocky
reefs, where it feeds on organic sediments. This species, reported as a possible new
species when it was collected at Islas Lobos de Afuera (Hooker et al. 2005), should
be reevaluated in order to clarify doubts concerning its taxonomy identity.
On shallow sandy bottoms the dominant echinoderms are the seastars Astropecten spp., with A. armatus as the most frequent (Fig. 8.4a). The sand dollar
Encope micropora has also been reported from this habitat, but seems to be more
frequent in the biogeographic transition region. Luidia bellonae is rarely reported
in deeper waters (10–20 m) along the north Peruvian coast. However, it is fairly
common in Islas Lobos de Afuera. There are no records of this species south of
Islas Lobos de Afuera. Nevertheless, Clark (1910), Anonymous (2010) and
Morales-Montecinos (2011) reported it from central and southern Peru. In waters
below 50 m depth, L. superba is the dominant seastar, together with Clypeaster
europacificus. Both species are frequently caught in artisanal fishing nets.
8.3.3 Tumbes Mangroves
Northern Peruvian mangroves possess a typical Tropical Eastern Pacific fauna but
the reported faunal diversity is low. The most representative species is Mellitella
stokesii, a very common sand dollar in sandy tide pools and intertidal beaches in
the interface between the mangroves and the sea (Fig. 8.4d). Another abundant
species is the sea urchin Agassizia scrobiculata. Dense populations occupy the
bottom of tidal creeks at depths between 0.5 and 2 m at low tide. The brittle star
O. magnifica is also frequent, mainly between mangrove roots and inside sponges
and zoanthids. Another ophiuran, an unidentified species of the genus Ophiogrammus, has been recorded in the muddy sand bottoms. A bright-orange morph of
Luidia brevispina is common on sandy beaches around mangroves, different from
the grey specimens known from Lobos de Afuera.
8.3.4 Biogeographic Transition Area Temperate South Eastern
Pacific-Tropical Eastern Pacific
As mentioned earlier, the transition area between these biogeographic provinces is
between Cabo Blanco (4°15
0 S) and Punta Aguja (6°S). This also includes the
islands Lobos de Tierra and Lobos de Afuera. Echinoderms of both provinces are
found in this refuge area as well as clear differences in abundance. For example,
O. magnifica is extremely abundant in almost every habitat, with the exception of
mud and fine sand bottoms. Another abundant species is Neothyone gibber,
especially at Lobos de Tierra where it covers 100 % of the vertical walls of large
rocks (Fig. 8.5e). Intertidal cliffs are dominated by H. helianthus. The sea
8 Echinoderms of Peru
291