Lesticus finisterrae Will and Kavanaugh

Will, Kipling & Kavanaugh, David H., 2012, A new species of Lesticus Dejean, 1828 (Coleoptera, Carabidae) from the Finisterre Range, Papua New Guinea and a key to the genera of pterostichine-like Harpalinae of New Guinea, ZooKeys 246, pp. 27-37 : 29-33

Lesticus finisterrae Will and Kavanaugh sp. n.

Holotype.

Male. "PAPUA NEW GUINEA, Madang/Morobe Province border, Finisterre Range, Teptep area, 3.5 air km WNW of Kewieng No.4 village, 3050 m, 28 March 1989 stop #89-50// D. H. Kavanaugh, G. E. Ball & N. D. Penny collectors, Cal. Acad. Sci. Specimen//Papua New Guinea Expedition - 1989// California Academy of Sciences Type No. 18684//HOLOTYPE Lesticus finisterrae Will & Kavanaugh [red label]". Deposited CASC.

Type locality.

Finisterre Range, Papua New Guinea. 5.99778°S, 52280°W.

Diagnosis.

This species shares with other Lesticus species sharply hooked mandibular apices, relatively broad mentum, extremely wide gula (nearly the width of the mentum) and has the general form of a modified species of the Lesticus chloronotus group. It is distinguished from all other species of Lesticus , including the New Guinea species covered in Darlington’s keys and descriptions (1962, 1971) and Dubault et al.'s key (2008), by the combination of three or more setae in elytral intervals 3 and 5, the absence of transverse sulci of abdominal ventrites 4-5 and the presence of extremely prominent eyes.

Description.

(Fig. 3), Size. Overall length (sbl) 20.0mm, greatest width over elytra 8.5mm. Color. Dorsal and ventral surfaces black to brunneous. Legs, mouthparts, and antennae slightly paler, lateral margins of pronotum and lateral and sutural areas of elytra margins piceous to rufopiceous. Luster. Dorsally and ventrally shiny. Iridescence. Elytra and ventral surface of body without spectral iridescence. Head. Dorsal microsculpture absent, entire surface with micropunctulae, clypeal-ocular sulci impression absent, shallowly rugose above eyes, with broad, shallow paramedial depressions, ocular ratio (greatest width over eyes/width between eyes at level of anterior supraorbital setae) 1.29, eyes moderately large size, very prominently “bulging”. Labrum with anterior margin slightly emarginate, with six setae of which medial four setae equally distributed in medial half, distance from outermost medial seta to lateral seta about twice distance between medial setae. Antenna overall length moderately long, antennomere 11 just reaching beyond pronotal base. Thorax. Pronotum transverse, lateral margin sinuate near base, medial and basal setae touching lateral marginal bead; basal impressions obsolete; anterior angles scarcely produced; microsculpture not visible at 50 × magnification; entire surface covered with minute punctulae. Elytral striae extremely shallow, scarcely impressed or absent; base of elytra not margined; humeri prominent but rounded; parascutellar punctures present at base of striae 1; interval 1 with two punctures at apex; interval 3 with three (right) or six (left) punctures; interval 5 with three (right) or four (left) punctures; interval 7 with one puncture near apex; interval 9 with 20 evenly spaced punctures; elytral microsculpture visible at 50 × as irregular isodiametric mesh of microlines; entire surface with micropunctulae. Male protaromeres 1-3 expanded with squamose setae ventrally. Tarsomere 5 on all legs ventral setose. Metatrochanter without setae. Metacoxa with single lateral seta. Abdomen. Abdominal ventrites smooth, glabrous except for very shallowly impressed transverse sulcus on last ventrite. Male with two setae on last ventrite. Aedeagus (Fig. 4) with small, dissimilar conchoid parameres; right paramere with large dorsal process (Fig. 4D); left paramere with a minute transverse apophysis (Fig. 4C). Median lobe with apex truncate; ostium dorsal; endophallus with small median sclerite.

Etymology.

The specific epithet finisterrae refers to the type locality, the Finisterre Range. Additionally, Finisterre is a contraction that derives from the Latin Finis Terrae, meaning "End of the Earth", an appropriate metaphor for this remote and entomologically little-known region. Although terrae is the genitive form, the contraction is treated as a noun in apposition since the "end of the Earth" is used as the name for the location.

Habitat.

Only a single specimen of Lesticus finisterrae is known. It was collected in an unbaited pitfall trap placed in upper montane moss forest at an elevation of 3050 meters. The area was near the upper limit of forest growth and adjacent to open grassland (Fig. 2). Under the forest canopy, a fairly dense understory of low vegetation was present (Fig. 1).

Identification and systematics.

“Trigonotomi” sensu Dubault et al. (2008) includes Lesticus , Trigonotoma , Euryaptus and Pareuryaptus . Although the group has not been rigorously tested for monophyly, it is reasonable to maintain its use as a working hypothesis based on similarity. Additionally, the genus Nesites Andrewes (cotype examined), which has the same combination of characters as Trigonotoma , should be included. It is likely that Trigonotoma and Nesites will prove to be synonymous. Lesticus finisterrae has the following states for characters given by Dubault et al. (2008): antennomere 1 less than combined length of antennomeres 2+3; setae at the anterior margin of the labrum more or less equally distributed; three or more setigerous punctures on interval 3 of the elytral disc. Females of Lesticus have four setae (two pairs) on the last ventrite, but the female for Lesticus finisterrae is unknown. The parascutellar striae are generally present and long in Lesticus species; however in Lesticus finisterrae all striae are very shallow or not impressed. There is no indication of the parascutellar striae. Lesticus finisterrae deviates from other species of Lesticus by the extremely prominent eyes, depressed form and lack of sulci on the abdominal ventrites. Based on general similarity and adjacencies of ranges, it seems probable that Lesticus finisterrae is an isolated and derived member of the Lesticus chloronotus group.

Key to pterostichine-like Harpalinae

Below is a revised key to the genera of “pterostichites” of New Guinea based on the key by Darlington (1962: 499-500). We have excluded Mecyclothorax Sharp ( Moriomorphini , Liebherr 2011), which was included in Darlington’s key, as it is not a member of the Harpalinae and only distantly related. It is easily distinguished from all the included taxa by the presence of a fixed seta in the mandibular scrobe.

Additional records

Stegazopteryx ivimkaensis Will

A male specimen labeled "INDONESIA W-PAPUA 130km SE Kalmana, Omba (=Yamor) river 10-20km from coast, 4°05'49"S, 134°54'09"E, 10-20m, 09.-11.II.2011 leg. A. Skale (008)." Specimen deposited ZSM.

This specimen record extends the range of this species into eastern West-Papua. This specimen, the two female syntype specimens and the further records below, are all from elevations of 120m and below. This species is now known to range across nearly all of New Guinea. The examined male specimen is consistent with the description: of the genus based on females as given by Will (2004), with the following additions. sbl=5.4mm, greatest width of elytra 2.3mm. Secondary sexual characters- male protarsi not expanded but with spatulate setae ventrally on tarsomeres 1-3. Last ventrite with one pair of setae. Aedeagus right side up in repose. Right paramere larger and conchoid, left paramere small, peg-like. Median lobe of adeagus simple, no evident sclerotized structure on the endophallus (Fig. 5).

Additional locality records (not examined, Martin Baehr, in litt.). PAPUA NEW GUINEA Canopy Mission, Madang Province, Baiteta, Light, Leg. Olivier Missa: 1 male- AR 53, 30-V-1996; 1 male, 1 female- T 2, 31-V-1993; 1 female, X G, 24-IV-1996; 1 female, M 2, 30-IV-1996. One male and two females deposited IRSNB, one male and one female ZSM.

Rhytisternus laevis (Macleay)

A female specimen labeled "New Guinea, Weam, Aug 1962// H. Olmus collector". Deposited ANIC. This species is distributed across northern Australia and it has not been previously reported from New Guinea. It is likely a recent accidental introduction or dispersal. We have only seen this single individual from New Guinea and it is unknown if the species is established.