Hilophyllus penai ( Martínez, 1976 ) Paulsen & Mondaca, 2006

Paulsen, M. J. & Mondaca, José, 2006, Revision of the South American Ceratognathini (Coleoptera: Lucanidae: Aesalinae) with the description of a new genus and a new species, Zootaxa 1191 (1191), pp. 1-19 : 8-11

Hilophyllus penai ( Martínez, 1976) , new combination

( Fig. 1, 4–5, 7, 16, 22, 25)

Ceratognathus penai Martínez, 1976: 101 .

Type specimens

Holotype male (FMNH) labeled: a) “CARAMAVIDA / Nahuelbuta (W)”; b) “(Arauco) 750 m / 25–31 Dic. 53 / Coll: L.E. Pena ”; c) on pink paper, “ HOLOTYPUS ”; d) on red paper, “ Ceratognathus / penai (male symbol) / sp. nov.” / (typeset) “A. MARTÍNEZ – DET. 19__”, (handwritten) “75”; e) “FMNH, 1986 / L.E. Pena Coll. / Acc. “17­422”. One paratype male (CMNC) labeled: a, b as holotype; c) on yellow paper, “ PARATYPUS ”; d) as holotype but on yellow paper; e) “H. & A. HOWDEN / COLLE CTION / ex. A. Martinez coll.” One paratype male (CMNC) labeled exactly as other paratype, except date of collection “1–10 Enero 54”. A female specimen subsequently labeled as “ ALLOTYPE ” by Martínez (FMNH) was not listed in the original description and is not part of the type series.

Redescription

Male (n = 5). Length: 8.4–8.9 mm. Width: 3.4–3.5 mm. Color/Surface: Reddishbrown to dark brown, weakly shining. Dorsum ( Fig. 1) covered with large punctures, many with a single elongate, apically acute scale; scales unicolored, testaceous or golden yellow. Head: Interocular width more than 2x width of eye in dorsal view. Mandibles ( Fig. 5) small, interlocking when closed, not longer than 1/2 length of head, apical tooth curved inward at middle in male; dorsal tooth broad, obtuse; ventral tooth of right mandible present, variably developed, weak or reduced to angulation. Antennal club segments elongate, as long as length of head. Pronotum: Sides narrowly explanate. Anterior angle slightly produced, not constricted toward head. Lateral margin broadly rounded, widest at middle. Elytra: Punctures lacking scales distributed in irregular patches. Legs: Mesotibiae with external tooth. Male genitalia: Parameres elongate, simple at apex ( Fig. 19).

Female (n = 4). Differing from male in following characters: Length: 9.0– 9.5 mm. Width: 3.9–4.0 mm. Head: Width of eyes together in dorsal view subequal to 1/3 interocular width. Mandibles small, not strongly curved inward at middle ( Fig. 4); dorsal tooth small, acute; ventral tooth of right mandible reduced to barely perceptible angulation. Antennal club segments short, as long as 1/2 length of head ( Fig. 4). Pronotum: Sides more narrowly explanate. Anterior angles constricted toward head. Lateral margin not uniformly rounded, pinched inward anteriorly. Genitalia: See Fig. 22.

Diagnosis

This species is distinguished by the presence of an external tooth on the mesotibia. In addition, the elytral scale pattern is formed with irregular patches of unicolored, light golden yellow scales that contrast with irregular patches that lack scales. The club segments of the male antennae are much shorter than in males of the other species, being only subequal in length to the head and mandibles combined.

Distribution ( Fig. 25)

CHILE: VIII Región. This species is apparently restricted to the forests on the west slope of the Nahuelbuta Cordillera (see Remarks).

Locality Data. 9 specimens examined.

CHILE (9). VIII Región: Contulmo (1), west of P.N. Nahuelbuta (8).

Temporal Data. September (1), December (7), January (1).

Remarks

Hilophyllus penai was previously known from only four specimens. Lack of knowledge of the species' natural history probably added to its perceived rarity. In 2004, we first collected a male and female of this species west of Parque Nacional Nahuelbuta by splitting a fallen branch with an approximate diameter of 10 cm. Subsequently, JME observed a male specimen sitting on a partially buried log. The log (possibly Nothofagus , Nothofagaceae ) contained termite galleries of the species Porotermes quadricollis (Rambur) (Termopsidae) , and dissection of the log resulted in the collection of two female specimens of H. penai among the galleries. Because of this, we hypothesize that species of Hilophyllus may be termitophilous. However, there are no apparent morphological adaptations to termitophily in this species such as those found in other inquiline lucanids (e.g. Penichrolucanus Deyrolle ). It is interesting to note that at least one New Zealand ceratognathine, Holloceratognathus passaliformis (Holloway) , is myrmecophilous, residing in the galleries of the ant Prolasius advena (Smith) ( Holloway 1962, 1998).

Based on the material available we hypothesize that this species is restricted to the western side of the Cordillera Nahuelbuta ( Fig. 25). Label data on one specimen indicates that it was collected on the lower portion of the slope in Monumento Natural Contulmo, which is at an approximate elevation of 300 m. We collected specimens from 985 to 1085 m. While Parque Nacional Nahuelbuta is adjacent to the range of this beetle, the park contains little of the western slope of the Cordillera. None of our specimens from 2004 were collected inside the park. Moreover, the western slope near P. N. Nahuelbuta is being vigorously deforested and the natural vegetation replaced with pine plantations. Unless the Parque Nacional Nahuelbuta is expanded westward to include habitat from the western slopes, only the tiny M. N. Contulmo (82 hectares, or 0.82 km 2) provides protected habitat for the survival of this and other species restricted to the area, including other stag beetles (e.g., Pycnosiphorus franzae Weinreich ).