Idioneurula donegani Huertas & Arias, new species
Creators: name: Huertas, Blanca
name: Arias, John Jairo
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Nymphalidae
Idioneurula
Idioneurula donegani

description: Idioneurula donegani Huertas & Arias, new species
Holotype m: Colombia, Santander, Serranía de los Yariguíes, Municipios El Carmen/Simacota, Lepipuerto 3000m, 06°28’N; 73°28’W, west slope; January 2005 (Huertas & Arias leg.). Deposited in IAvH, Colombia. Allotype Colombia, Santander, Serranía de los Yariguíes, Municipio de Galán, Filo Pamplona 3200m, 06º38’N; 73º24’W; east slope. June–July 2005 (Huertas, Arias & Ríos leg.) Paratypes 7m, same data as the holotype. 14m and 2f, data as the allotype. Deposited in MHN-UC, JFLCPC and to be deposited in BMNH and other collections. No other specimens of I. donegani were found in the consulted collections or at other study sites in the Yariguíes.
For specimens of other taxa consulted in collections, see Appendix I.
Diagnosis. Idioneurula donegani n. sp. most closely resembles the two described Idioneurula species (I. erebioides and I. eremita) and Tamania jacquelinae in its morphology (Figs. 2 A–D). Idioneurula are small to medium sized butterflies with a rather triangular-shaped forewing, plain brown coloured wings, no markings on the dorsal forewing, at least one ocellus on the lower border of the dorsal hindwing, such ocelli generally black with a yellow or orange border and white centre spot, no marked sexual dimorphism, high elevation distribution in the East Andes (Fig. 1), broadly similar male genitalia with proximal opening for the aedeagus hirsute and concave and small spines on the proximal tip of the aedeagus (Figs. 3 A–D).
I. donegani n. sp. differs from I. erebioides and I. eremita in its larger overall size (wings: Table 1, antennae and abdomen), dark antennae (with no yellowish tip), wing shape (more rounded in I. donegani, more triangular in I. erebioides and I. eremita), absence of scales on borders of wing forming a hairy appearance, darker dorsal coloration of both wings, greater number of ocelli (always 4 or 5) on dorsal hind wing (HW) (from I. erebioides only) and ventral HW underside pattern; presence of dark brown zigzagging postmedian line and a series of 4–5 small submarginal ocelli with white pupils, similar to I. eremita, whereas in I. erebioides the pattern is indistinct, the ocelli faint or absent and the ventral HW often has intervenous cream stripes; and in male genitalia by a process of heavily sclerotization on dorso-distal valva. Idioneurula donegani differs from T. jacquelinae in its wing ground colour being less chestnut-brown in males and in the presence of zigzag pattern on HW; absence of ocelli on dorsal forewing (FW) (Figs. 2 A–D); and in male genitalia as for the other species above. Notably, Pyrcz (1995) gave as diagnostic feature of Tamania that it exhibited “only one prominent M2–M3 cell ocellus on the upper and under surface of both wings”. Idioneurula donegani lacks this ocellus on the FW (Fig. 2). Despite the general similarity in size, differences are observed in average wing length between these species (Table 1). I. donegani has a greater range of variation in this measurement perhaps due to sampling in two different and distant localities.
Morphology. MALE: (Fig. 2 A, Figs. 5 C–F). Head: Eyes naked, dark coffee brown; palpi three times longer than head, densely hirsute, dorsally light brown, ventrally brown; antennae composed of 34 segments, brown except for dorsal surface of club, which is light orange chestnut, shaft with brown scales on dorsal and white on ventral sides, club 2.5 times as broad as shaft. Thorax: dark brown, covered with hairy scales. Abdomen: dorsally dark brown. Ventrally gray with many scales. Wings (Fig. 4): Forewing mean 23.7 mm; range 20.6–27.5 (n=22), hairy, dorsally lustrous reddish brown (average 10YR 2/ 2 in Munsell (1977, 2000); cf. average 7.5YR 3/4–4/ 6 in I. erebioides), ventrally lighter and more brilliant. FW roughly triangular, apex and tornus obtuse; Sc independent of R1–R2. FW ground colour brown, progressively darker towards base, ventral discal region limited by two zigzag dark brown lines and another similar orange line separating marginal and submarginal regions and ventral FW wing edges, flanked with orange scales. Sparse reddish scales over all FW and HW. HW oval, margins rounded. Dorsal ground colour dark brown with thinly mottled orange scales around medial region; dark and tiny brown scales flanking margins of wings; two strongly marked dark brown zigzag lines, bordered with a thin line of orange scales, limiting submarginal area; dark brown line in marginal region bordering wing; between the lines are a series of four ocelli in cells M2-M3 to Cu1-Cu2, first three 3–4 mm diameter, whilst a fifth ocellus in Cu2-1A is reduced to 2–3 mm or less, sometimes vestigial but never absent; ocelli black, circled by ochreous yellow and finely pupilled with white. HW ventral ground colour brown (lighter than dorsal) darker towards base with two thin dark brown zigzag lines limiting submarginal region; ventral surface densely covered with short hair scales; series of four or five small ocelli from cell M2-M3 to Cu2-A1, black, pupilled with white and diffusely circled by yellow ochreous and dusted with reddish scales. Genitalia: (Figs. 3 A–D). Uncus elongated, ending with a rounded hook. Subuncus short, about one third length of uncus, horn-shaped and slightly pointed. Valva medium-sized, wide dorsal process of valva, rounded tegument and heavily sclerotized disto-dorsally. Vinculum rather long and thin. Aedeagus thin and long with small spines on the proximal tip and proximal opening concave and hirsute. Immature stages unknown.
FEMALE: Forewing mean 24.7mm; range 24.0–26.0 (n=3). Similar to male except as follows. Forewing length slightly longer on average. Wing shape more rounded on average. Background pattern similar to males but zigzag more strongly marked in dorsal forewing. Colour c. 3/3 10 YR (Munsell 1997, 2000), as T. jacquelinae, paler than males on average. Line in hindwing marginal border more yellow (intense). Ocelli larger and five present on all specimens. Three to four ocelli in ventral hindwing. Genitalia: (Figs. 3 E–F) Large sclerotized sterigma broadly rounded, with conspicuous “nose” beneath ostium bursae. Ductus bursae very short; corpus bursae large, membranous almost spherical, paired signum composed of two narrow bands of densely set teeth, signa almost as long as corpus bursae.
Distribution. Idioneurula donegani is known only from Serranía de los Yariguíes, in páramo habitat at 2900–3200m elevation. Idioneurula erebioides is found at similar elevations (2250–3200m) but in the main East Andes and ranges further south (Cundinamarca to Boyacá: found at Arcabuco, SFF Iguaque, Sierra Nevada del Cocuy and Bogotá region). I. erebioides and I. donegani are not known to be sympatric (Fig. 1). On the north-eastern slope of the Cordillera Oriental in the region of Tamá, Tamania jacquelinae (2200– 2500m) and Idioneurula eremita (2400–3350m) are found, with the latter replacing the former at higher elevations (Pyrcz 1995; Viloria 1998). Idioneurula donegani has not been found in the main range of the East Andes, suggesting that it may be endemic to Serranía de los Yariguíes. The páramo habitats of the Yariguíes are isolated from others in the northern East Andes by a dry region of lower elevation in the valleys of the rivers Chicamocha and Suárez and by depressions associated with the ríos Horta and Opón. The isolation of the Yariguíes páramo systems possibly may have led to differentiation of high elevation taxa such as I. donegani. Several endemic undescribed bird taxa were also found in the Yariguíes páramo (Donegan et al. 2007).
Habitat and ecology. Yariguíes páramo is characterised by low vegetation with spiny plants (Figs. 5 A-B). We observed Blechnaceae ferns (Blechnum schomburgkii), Eriocaulaceae (Paepalanthus), Ericaceae, Clusiaceae, Bromeliaceae, Melastomataceae, Orchidaceae and Asteraceae (e.g. Espeletia) in this habitat. Other shrub species were present, with some isolated palms and dry shrubs of less than 1.5m height. Other Idioneurula and Tamania species occur in marshy areas (bogs) and their host plants are grasses (e.g. Calamagrostis, Stipa) or sedges (Cyperaceae) (Pyrcz 1995; Pyrcz & Viloria 2007), whilst I. donegani was not found in marshy habitat. Few Gramineae and Cyperaceae plants were however found in I. donegani ’s habitat below and at the treeline. In this habitat, there is frequently direct sunlight from about 0800hrs to midday, and then in the afternoon strong winds, torrential downpours and violent thunderstorms occurred daily. Idioneurula donegani was observed with greater frequency in Filo Pamplona, possibly due to the season of collection (end of rainy season). I. donegani was frequently seen on ground-dwelling plants of Paepalanthus (Platycaulon) Mart. (Eriocaulaceae) and flying no more than 1.5 m above ground level. It is active when ground-level mist or cloud is present and less active during times of strong insolation. When resting, it holds its wings in an unusual manner (<180°) (multiple observations). It rests during the afternoon and during rain was observed under the leaves of an ericaceous plant (Fig. 5 D).
Etymology. The name donegani is formed as the genitive singular of a fictional second declension masculine Latin noun. The epithet is dedicated to Thomas Michael Donegan, EBA project director and a pioneer of the expeditions to Serranía de los Yariguíes. Fieldworker and researcher in Colombia for 10 years, Thomas has contributed to our knowledge of Colombian biodiversity through exploration, description of various new bird taxa and by supporting young Colombian researchers. Beloved husband and co-worker of the first author.
Conservation. In addition to Idioneurula donegani, the Serranía de los Yariguíes harbours a number of undescribed and recently described taxa (e.g. Donegan & Huertas 2006; Donegan et al. 2007; Huertas & Ríos MS). Despite topographical difficulties and complexity of access, human pressure for agriculture and livestock are mounting issues. During the EBA and YARÉ expeditions, deforestation, hunting and anti-personnel landmines were observed, complicating conservation efforts. Conservation of páramo habitats is clearly necessary for this species. In the YARÉ project, considerable conservation-oriented community work was carried out (see further in Huertas & Donegan 2006). Deforestation and other threats could potentially be reduced through education programmes and encouraging treatment of páramos as water sources that should not be modified. Subsequent to the EBA and YARÉ projects’ fieldwork and other important local input, Serranía de los Yariguíes was declared a National Park (Ministerio del Medio Ambiente, Desarrollo y Vivienda 2005), an Alliance for Zero Extinction site (Ricketts et al. 2005) and an Important Bird Area (AICA) (Franco & Bravo 2005). Additionally, Fundación ProAves has established a nature reserve in the region.
A range and conservation assessment follows, based on the assumption that I. donegani is endemic to Serranía de los Yariguíes, considering the number of Idioneurula specimens inspected from nearby regions. The Yariguíes mountains attain suitable elevations for this species (over 3000m) with undisturbed habitat for c. 25 km of their length and an average of c. 1000 m laterally (IGAC 1995; IGAC 1999), producing an estimated area of suitable habitat of 25 km 2 for the new species. We have insufficient data to determine a population estimate for I. donegani or population trends which are important for conservation assessments. However, the relative intactness and remoteness of habitats at high elevations in the Yariguíes suggests that the population is unlikely to be declining by>30% over ten years (IUCN criterion A), nor that the habitat is "severely fragmented" (IUCN criterion B). The inaccessibility of the new species' habitat, I. donegani 's relative abundance where found and the protected status of the Serranía de los Yariguíes each give some hope for the species' long term conservation. However, I. donegani's apparently very small range mean that it should be categorised as a threatened species (Vulnerable) under category D2 (known from less than 5 localities).
description: Published as part of Huertas, Blanca & Arias, John Jairo, 2007, A new butterfly species from the Colombian Andes and a review of the taxonomy of the genera Idioneurula Strand, 1932 and Tam an i a Pyrcz, 1995 (Lepidoptera: Nymphalidae: Satyrinae), pp. 27-40 in Zootaxa 1652 on pages 30-34, DOI: 10.5281/zenodo.273998