Research Article |
Corresponding author: Carlos Perafán ( caperafanl@gmail.com ) Academic editor: Ingi Agnarsson
© 2016 Carlos Perafán, William Galvis, Miguel Gutiérrez, Fernando Perez-Miles.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Perafán C, Galvis W, Gutiérrez M, Pérez-Miles F (2016) Kankuamo, a new theraphosid genus from Colombia (Araneae, Mygalomorphae), with a new type of urticating setae and divergent male genitalia. ZooKeys 601: 89-109. https://doi.org/10.3897/zookeys.601.7704
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A new monotypic Theraphosidae genus, Kankuamo Perafán, Galvis & Pérez-Miles, gen. n., is described from Colombia, with a new type of urticating setae. These setae differ from others principally by having a small distal oval patch of lanceolate reversed barbs. Males of Kankuamo gen. n. additionally differ by having a palpal bulb organ very divergent from all known species, with many conspicuous keels dispersed across the median tegulum to the tip, mostly with serrated edges. Females differ by having spermathecae with a single notched receptacle, with two granulated lobes and several irregular sclerotized longitudinal striations. The new urticating setae, type VII, is characterized, illustrated and its releasing mechanism is discussed. It is hypothesized that these setae are the first in Theraphosinae subfamily whose release mechanism is by direct contact. Kankuamo gen. n. is described and illustrated on the basis of the type species Kankuamo marquezi Perafán, Galvis & Gutiérrez, sp. n., and their remarkable characteristics, morphological affinities and cladistic relationship are analyzed.
New species, Sierra Nevada de Santa Marta, Theraphosinae phylogeny, urticating setae type VII
Theraphosidae Thorell, 1869 is the most speciose of the Mygalomorphae with more than 130 genera and 980 species (World Spider Catalogue 2015), mainly distributed in the tropical and subtropical regions, and currently divided into 11 subfamilies (
The morphological characteristics of urticating setae have long been used in taxonomy and systematics of Theraphosidae, being useful as a set of characters for differentiation of subfamilies and genera as shown in phylogenetic analysis (
During study of Colombian tarantulas, we discovered specimens from Sierra Nevada de Santa Marta, Colombia, with a different type of urticating setae which did not fit with any known types. These setae mainly differ by having a small distal patch of reversed lanceolate barbs (regarding the main barbs; sensu
Based on its unique combination of characters, we propose the new monotypic Theraphosinae genus Kankuamo Perafán, Galvis & Pérez-Miles, gen. n., which is here diagnosed, described and illustrated on the basis of the type species Kankuamo marquezi Perafán, Galvis and Gutiérrez sp. n. Morphological aspects are discussed and its phylogenetics relationship are analyzed based on a Theraphosinae cladistic re-analysis presented in this paper. Considering the size and morphology of the urticating setae in Kankuamo gen. n., we propose them as a novel type, here naming them as type VII urticating setae. These setae are described and illustrated, and their releasing mechanism is discussed.
Urticating setae terminology follows
Abbreviations are listed below:
AcK accessory keels
AK apical keel
ALE anterior lateral eyes
AME anterior median eyes
ap apical
D dorsal
DKs dorsal keels
k concavity constant
OQ ocular quadrangle (including lateral eyes)
P prolateral
PIK prolateral inferior keel
PME posterior median eyes
PMS posterior median spinnerets
PLE posterior lateral eyes
PLS posterior lateral spinnerets
PSK prolateral superior keel
SAK subapical keel
SpAcK supra-accessory keels
R retrolateral
V ventral
Cladistic analysis. Cladistic analysis was based on the previous matrix of Theraphosinae genera used by
A data matrix composed of 37 morphological characters and 35 genera has been constructed (Table
Character matrix used in cladistic analysis of Theraphosinae genera. (?) inapplicable, unknown or doubtful.
0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 1 0 | 1 1 | 1 2 | 1 3 | 1 4 | 1 5 | 1 6 | 1 7 | 1 8 | 1 9 | 2 0 | 2 1 | 2 2 | 2 3 | 2 4 | 2 5 | 2 6 | 2 7 | 2 8 | 2 9 | 3 0 | 3 1 | 3 2 | 3 3 | 3 4 | 3 5 | 3 6 | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Guyruita | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Acanthoscurria | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | ? | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 2 | 0 |
Aphonopelma | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | ? | 1 | 0 |
Brachypelma | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 0 | 0 | 0 | 1 | 0 | 1 | 2 | 0 |
Bumba | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | ? | 0 | 1 | 1 | 0 |
Citharacantus | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ? | 0 | 1 | 0 | 1 | 1 | 0 |
Clavopelma | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | ? | ? | ? | ? | ? | ? | ? | ? | 0 |
Cyclosternum | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 2 | 0 |
Cyriocosmus | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 |
Cirtopholis | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | ? | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 |
Euathlus | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 |
Eupalaestrus | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 2 | 0 | 1 | 0 | 1 | 2 | 0 |
Grammostola | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 |
Hapalopus | 1 | 1 | ? | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 4 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 2 | 0 |
Hapalotremus | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 4 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 0 |
Hemirrhagus | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ? | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 |
Homoeomma | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 0 | ? | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | ? | 1 | 0 | 0 |
Lasiodora | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 0 |
Megaphobema | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 0 |
Melloleitaoina | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 |
Metriopelma | 1 | 1 | 0 | 1 | 2 | 0 | 0 | 0 | 0 | 0 | ? | ? | 1 | ? | 0 | 0 | 1 | ? | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ? | ? | 0 | 0 | 1 | 0 | 1 | 2 | 0 |
Nhandu | 1 | 1 | 0 | 1 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 2 | 1 | 0 | 1 | 0 | 1 | 2 | 0 |
Pamphobeteus | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 2 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 2 | 0 | 0 | ? | 0 | 1 | 1 | 0 |
Phrixotrichus | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | ? | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 |
Phormictopus | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 2 | 0 | 1 | 0 | 1 | 1 | 0 |
Plesiopelma | 0 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | ? | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 |
Schizopelma | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | ? | 3 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ? | ? | ? | 0 | 1 | 0 | 1 | ? | 0 |
Sericopelma | 2 | 1 | 0 | 1 | 2 | 0 | 0 | 0 | 0 | 0 | ? | 3 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 0 | 0 | 0 | ? | ? | 1 | 2 | 0 |
Sphaerobothria | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 0 |
Theraphosa | 2 | 1 | 0 | 1 | 2 | 0 | 0 | 0 | 0 | 0 | ? | 2 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 1 | 2 | 0 |
Thrixopelma | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 2 | 0 |
Tmesiphanthes | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 0 |
Vitalius | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 2 | 1 | 0 | 1 | 0 | 1 | 2 | 0 |
Xenesthis | 2 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 2 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3 | 2 | 0 | 0 | 1 | 0 | 1 | 2 | 0 |
Kankuamo | 1 | 1 | 0 | 1 | 2 | 0 | 0 | 0 | 0 | 0 | ? | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 1 | 1 | 0 | 1 | 2 | 1 |
Data set. Characters used in the cladistic analysis. The data matrix is listed in Table
(36) Urticating setae type VII: absent = 0; present = 1.
Kankuamo marquezi Perafán, Galvis & Gutiérrez, sp. n.
Differs from all previously known genera of Theraphosidae by having a distinct type of urticating setae (Fig.
Kankuamo gen. n., urticating setae type VII. A Distal apex, white arrow indicates patch of lanceolated reversed barbs, grey arrow indicates penetrating tip B patch of lanceolated reversed barbs C main barbs on distal area D main barbs on medial area E basal end and detail of main barbs on basal area, white arrow indicates the attachment stalk with the abdomen F–G abdomen, dorsal surface, showing setae attachment points, white arrow indicates urticating setae. Scale bars: A, F = 50 µm; B, E = 10 µm; C, D = 20 µm; E = 200 µm.
Kankuamo marquezi gen. n., sp. n., male. A Cephalothorax B labium and maxillae C right palpal bulb, ventro-prolateral view D tibia I in ventral view, showing absence of apophysis E-I left palpal bulb: E dorsal view F retrolateral view G prolateral view H-I detail of apex. AcK = accessory keels, AK = apical keel, DKs = dorsal keels, PIK = prolateral inferior keel, PSK = prolateral superior keel, SAK = sub-apical keel, SpAcK = supra-accessory keels. Scale bars: C, D and E, F, G = 1 mm.
Kankuamo is a noun in apposition and refers to the indigenous people of the Chibcha family from the Caribbean region of Colombia, which inhabits the eastern slope of the Sierra Nevada de Santa Marta, whose language and culture are at endangered. Kankuamo gender is neuter.
See description of the type species.
Only known from its type locality, Vereda San Lorenzo, Corregimiento Minca, Santa Marta, Magdalena, Colombia, 11.1 N, -74.05 W (Fig.
Morphology. Kankuamo gen. n. clearly presents the diagnostic characters of the subfamily Theraphosinae (Theraphosidae): male palpal bulb with large and extended subtegulum, and numerous developed keels; legs spinose, with normal scopulae on tarsi and presence of abdominal urticating setae (Figs
The spermathecae of Kankuamo gen. n. are similar to those of Theraphosinae genera with only one entire receptacle (e.g. Brachypelma Simon, 1891, Megaphobema Pocock, 1901, Mygalarachne Ausserer 1871, Sericopelma Ausserer, 1875, Theraphosa Thorell, 1870), but notched and longitudinally striated (Fig.
Accordingly, Kankuamo gen. n. clearly differs from all genera of Theraphosidae known by the urticating setae type and male palpal bulb characters.
A search using equal weights found 171 most parsimonious tress and the strict consensus of these did not provide any resolution. Search with implied weighting and different concavity indices (k = 3 to 12) found between 3 and 10 shortest trees. The strict consensus of each of these tress recovered different topologies, but between k = 8 and k = 12 the topology of strict consensus did not vary, for this reason we have selected this topology to test Kankuamo gen. n. affinities (Fig.
Kankuamo gen. n. was resolved as the sister group of Metriopelma, supported by the character “femur IV without retrolateral scopula”. Both genera also share the lack of the apophysis on males and a spermathecae with seminal receptacles completely fused. Kankuamo gen .n. presents a reversion to state (0) on character 16 “absence the urticating setae type I”, a parallelism of the state (1) on character 31 “presence the accessory keels under prolateral inferior keel” and an autapomorphic character “presence of urticating setae type VII”.
Kankuamo gen. n. and Metriopelma were resolved as sister genera within the largest clade of our selected topology. The relationship of Kankuamo gen. n. + Metriopelma as the sister group of the clade (Theraphosa (Sericopelma (Brachypelma (Megaphobema (XenesthisPamphobeteus) (Sphaerobothria (Phormictopus (CyrtopholisAcanthoscurria))))))) is supported by “absence of retrolateral keel” and “absence of sub-apical keel”, with some homoplasies. The Theraphosa clade is supported by two synapomorphies “apical region of palpal bulb with cancave-convex aspect” and “apical keel very long”.
Holotype male from Colombia, Magdalena, Santa Marta, Corregimiento Minca, Sector San Lorenzo, 2200m above sea level, 11.11 N, -74.058 W, 30-Aug-2014, leg. W. Galvis and J. Moreno (
The specific epithet is a noun in genitive in honor to Gabriel García Márquez (Aracataca, Colombia, 1927 - Mexico D.F., Mexico, 2014), who was a renowned Colombian writer, considered one of the most significant authors of the 20th century, and awarded the 1982 Nobel Prize in Literature for “One hundred years of solitude”.
See diagnosis of the genus.
Male (holotype
Spination (proximal to distal): Femur: palp: 0V, 0D, 0-0-1P, 0R; I: 0V, 1-1-0D, 0-1-1P, 0-1-2R; II: 0V, 1-1-0D, 1-1-3P, 1-5-2R; III 0V, 1-1-0D, 0-2-1P, 0-2-3R; IV: 0V, 3-2-0D, 1-2-1P, 0-1-2R. Patella: palp: 0V, 0D, 0-2-0P, 0R; I: 0-2-2V, 0D, 0-2-0P, 0R; II: 0-0-2V, 0D, 0-2-0P, 0R; III: 0V, 0D, 0-3-0P, 0-1-0R; IV: 0V, 0D, 0-3-0P, 0-1-0R.Tibia: palp: 2-1-2V, 0D, 2-2-2P, 0R; I: 4-6-2apV, 0D, 0-2-2P, 0-1-1R; II: 3-5-2apV, 0D , 0-1-1P, 0-2-0R; III: 3-3-2apV, 0D, 2-2-1P, 2-2-1R; IV: 3-3-2-1-2apV, 0D, 2-2-2P, 1-2-2-2apR. Metatarsus: I: 2-3-1V, 0D, 0-1-1apP, 0-1-1apR; II: 3-3-1V, 0D, 0-1-1-1apP, 0-1-1apR; III: 4-4-2-1apV, 0-0-2D, 2-2-1-1apP, 1-2-1-1apR; IV: 5-5-3-1apV, 0-0-2D, 2-3-1-1apP, 2-2-1-1apR. Tarsus: palp and legs: 0. Legs and palpal segments lengths in Table
Female (allotype
Spination (proximal to distal): Femur: palp: 0V, 0-1-0D, 0-0-3P, 0-0-1R; I: 0V, 0-1-0D, 0-0-3P, 0R; II: 0V, 0-2-0D, 0-0-3P, 0-1-0R; III: 0V, 0D, 0-2-1P, 1-3-1R; IV: 0V, 1-0-0D, 0-0-3P, 0-0-1R. Patella: palp: 0V, 0D, 0-2-0P, 0R; I: 0V, 0D, 0-1-0P, 0R; II: 0V, 0D, 0-2-0P, 0R; III: 0V, 0D, 0-2-0P, 0R; IV: 0V, 0D, 0-1-0P, 0R. Tibia: palp: 1-4-4V, 0D, 0-3-0P, 0-1-0R; I: 0-1-2V, 0D, 1-1-0P, 0R; II: 0-2-2V, 0D, 0-2-0P, 0R; III: 3-3-3V, 0D, 2-1-2P, 1-2-1R; IV: 2-2-2V, 0D, 2-2-1P, 2-2-1R. Metatarsus: I: 1-5-1V, 0D, 0-1-1P, 0R; II: 1-5-1V, 0D, 0-0-1P, 0R; III: 4-3-5V, 0-0-2D, 2-2-2P, 1-3-1R; IV: 5-4-5V, 0-0-2D, 3-3-2P, 1-2-2R. Legs and palpal segments lengths in Table
Length of legs and palp segments in millimeters of holotype male/allotype female Kankuamo marquezi gen. n., sp. n.
Segments | Palp | I | II | III | IV |
---|---|---|---|---|---|
Femur | 6.2 / 8.0 | 9.0 / 10.8 | 8.5 / 10.2 | 8.4 / 9.7 | 9.5 / 11.5 |
Patella | 2.8 / 4.5 | 4.5 / 6.0 | 3.9 / 5.7 | 3.5 / 5.0 | 3.8 / 5.4 |
Tibia | 5.8 / 6.0 | 7.4 / 8.0 | 6.9 / 7.6 | 6.3 / 7.0 | 8.0 / 9.3 |
Metatarsus | - | 7.0 / 8.0 | 7.0 / 7.5 | 7.8 / 8.6 | 10.9 / 12.0 |
Tarsus | 2.1 / 5.4 | 4.3 / 4.5 | 4.5 / 4.5 | 4.2 / 4.4 | 4.5 / 4.5 |
Total | 16.9 / 23.9 | 32.2 / 37.3 | 30.8 / 35.5 | 30.2 / 34.7 | 36.7 / 42.7 |
See distribution of the genus (Fig.
Kankuamo marquezi sp. n. inhabits Cuchilla San Lorenzo from Sierra Nevada de Santa Marta National Natural Park. Cuchilla San Lorenzo is located in its northwestern flank, in a gradient of altitude from 2000–2300 meters above sea level, in life zone of lower montane wet forest (
Morphology. Urticating setae differ from body covering setae by the insertion feature through a stalk (types I, II, III and IV) or attached into a specialized socket (types V and VI) that facilitates detachment, plus presence of a penetrating acute tip, and barbs or scales that aid embedding them into targets (
Urticating setae type VII are located in a dorsal wide area of the abdomen intermixed with the covering setae, and attached to the cuticle by a thinner stalk, to facilitate their release (Fig.
Main barbs are subtriangular denticles not homogeneous in size and density, longer on the basal region (Fig.
The patch of lanceolate barbs its located sub-apically at a distance approximately of 160µm from the tip to the patch centre (Fig.
Discussion. The newly characterized type VII urticating setae resemble the type II found in Aviculariinae (
The similarities of the morphology and size of setae type VII with type II Aviculariinae (see
Furthermore, the larger size, broader shape and often dispersed arrangement of many of the main barbs of Theraphosinae urticating setae (types I, III, VI, VI) involved in their urticating effects, presumably often contribute their ability to float in the air. Conversely, in both urticating setae types II and VII, which presumably do not float by air, the main barbs are only residual denticles, being much smaller than those of other types with known air dispersal.
The differences in the position of the penetrating tip between type VII and II also suggest a different penetration mechanism. On first contact with the target, the urticating setae type II pivots on its stalk so the apical end moves away from the target, while the basal penetration tip (which is actually adjacent to the stalk) instead lodges into the target as the stalk releases (see
Experimentally, the possible mechanism of action of the urticating setae type VII was observed while handling specimens in alcohol. These urticating setae easily perforated the skin of human fingers perpendicularly. The dorsum of the tarantula’s abdomen was touched intentionally, and on further examination of the affected fingers with a stereoscope microscope, many of these setae were found embedded in the skin (Fig.
Another aspect to consider is that all previously known species with contact urticating setae have leg spines absent or reduced (
Kankuamo gen. n. fits the diagnostic characters of Theraphosinae, but also shows a very divergent palpal bulb morphology and the presence of a new abdominal urticating setae type. These setae are unique, and here are proposed to be the only contact released urticating setae yet known within the Theraphosinae, although this release mechanism was previously well known only for Aviculariinae. Also, the supernumerary keels on the male palpal bulb clearly distinguish it from all known theraphosid species. Kankuamo gen. n. was resolved as the sister group of Metriopelma on our preferred phylogeny of Theraphosinae.
Research that gave rise to the results presented in this publication was funded by the Agencia Nacional de Investigación e Innovación (ANNI), Uruguay, under POS_NAC_2011_1_3624 code, which is greatly appreciated. Thanks to Stuart Longhorn for his valuable comments and criticism, and for English corrections. We also thank the reviewers and editors for their valuable contributions. Juan David Jimenez is thanked for providing us the photo of the locality, Fig.