Pogonostoma (Pogonostoma) mahimborondrense Moravec & Wiesner, 2022

Moravec, Jiří, Wiesner, Jürgen & Jocque, Merlijn, 2022, New or rare Madagascar tiger beetles- 26. A new species ofthe genus Pogonostoma Klug from northwestern Madagascar and a revised key to the Pogonostoma (P.) srnkai species-group (Coleoptera: Cicindelidae), Zootaxa 5169 (2), pp. 165-176 : 168-170

Pogonostoma (Pogonostoma) mahimborondrense Moravec & Wiesner sp. nov.

( Figs 1–12 , 13–16 )

Type locality. Northwestern Madagascar (district of Bealanana within Sofia Region ), Northern Highlands : Mahimborondro protected area, forest near Bekavahy, east of Bemanevika , –14.3006; 48.75161, 1586 m.

Type specimens. Holotype ♂ in IRSNB, labelled: “Coll. I. R.Sc.N.B. Madagascar, / Northern Highlands / Mahimborondro, near Bekavahy / –14.3006; 48.75161, 1586 m, / 6.II.2019 leg. Brett Gardner ” [printed] // “ On way to forest / close to camp” [printed] . Allotype ♀ in IRSNB with same label data except for: “near Matsabory Iadan’I Saza / –14.34154; 48.7051, 1616 m / 4.II.2019, leg. Dan Slootmaekers ” [printed] // “On tree trunk / in forest” [printed]. The two type specimens labelled: “ Holotype (“ Allotype ” respectively) / Pogonostoma (s. str.) / mahimborondrense sp. nov. / det. J.Moravec & J.Wiesner [red, printed] // “I.G.: 34.499” [depository number in IRSNB].

Differential diagnosis. This new species is immediately recognizable by its yellow-testaceous apices of femora and bases of tibiae, combined with markedly elongate-cylindric shape of pronotal disc and hooked aedeagus apex. Pogonostoma (P.) gibbosum Rivalier, 1970 is the only other species within the nominotypical subgenus which shares the leg coloration with the new species. It is, however, a species of the P. (P.) gibbosum speciesgroup and immediately differs from the new species in having its pronotal disc subglobose, distinctly gibbose, with tuberculate and densely hairlike setose surface (see Moravec 2007).

Description. Body ( Figs 1–2 ) medium-sized (within nominotypical subgenus), male HT 11.1 mm long, 2.80 mm wide, female AT 12.6 mm long, 3.20 mm wide, dorsally pitchy black except for yellow-testaceous apices of femora and basal quarter to third of tibiae; setal vesture white.

Head notably smaller than body (but wider than pronotum), width 1.20–1.40 mm, temples rather long, only 2 times shorter than eyes.

Frons-vertex. Frons indistinctly separated from clypeus (lacking visible suture) and fluently merging with vertex; supraantennal keels in shape of elevated, shortly sinuous anterolateral edge and smaller but distinct posterior one; frons-vertex and occipital surface rather finely scabriculous-rugulose throughout (partly very irregularly and becoming coarser posteriad) with two shallow sublateral anterolateral impressions which are indistinct in male, better noticeable in female (U-shaped impression unrecognizable); vertex-occipital impression shallow but distinct, more so in female, posterior area including temples with more coarse vermicular rugae, occipital area with more continuous, transverse-wavy rugae; anterior and median surface covered with rather copious whitish microsetae which are barely visible when impressed and therefore appear darkened.

Genae wrinkled on their posterior half, with few erected hairlike setae.

Clypeus irregularly wrinkled, covered with rather sparse hairlike setae.

Labrum black, matt-shiny, sexually dimorphic in number of anterior setae and shape: male labrum ( Fig. 5 ) 6-setose (with 4 anterior, and 2 lateral dark reddish-brown setae), its surface covered with scattered microtrichia; shape almost transverse, length 0.65 mm, width 1.20 mm; lateral margins moderately arcuate towards rather indistinct lateral indentations and distinct, right-angled anterolateral teeth; anteromedian margin irregularly sinuous with small anterior teeth on either side of shallow median excision; female labrum ( Fig. 6 ) notably more elongate, 1.00 mm long, 1.40 mm wide, lateral margins moderately arcuate, attenuated towards rather indistinct lateral indentations and small but acute anterolateral teeth, then prolonged anteriad, forming bilobed anteromedian lobe with irregularly dentate anterior margin on either side of deeper median excision.

Maxillae black, lacinia elongate, apex moderately dilated, 0.25–0.29 mm wide; setae reddish-brown.

Palpi ( Figs 1–2 ). Both maxillary and labial palpi black except for brownish to brownish-testaceous apical areas of terminal palpomeres (as in other species of the nominotypical subgenus); setae black or with reddish tinge.

Mandibles ( Fig. 4 ) black with black-brown teeth (or only their apices), subsymmetrical with only slightly elongate terminal teeth; terminal tooth of left mandible shorter and slimmer than that of right mandible; second tooth in left mandible of male thinner and slightly smaller than third one; in right mandible with third tooth slightly smaller than second tooth (inner teeth in left mandible of female almost equally sized, second tooth of right mandible in female larger than third one).

Antennae ( Figs 1–2 ) longer than body in male, shorter in female, entirely black, antennomeres 1–4 with faint metallic greenish lustre (in male HT), with sparse barely visible microtrichia; antennomeres 5–11 with usual greyish micropubescence.

Thorax. Pronotum ( Figs 7–8 ) notably elongate, length 2.80–3.00 mm, width 1.40-1.65 mm, anterior lobe only slightly narrower than posterior one, very shallowly irregularly or more transversely wrinkled, glabrous; disc markedly elongate-cylindric with almost parallel lateral margins, median line indistinct, notopleural sutures in dorsal view obvious in posterior third only, surface finely but distinctly transversely striate-rugulose throughout, rugae occasionally anastomosing, mostly on anterior and lateral areas; juxtanotopleural areas indistinctly tuberculate (in male with only few tubercles on anterior-juxtanotopleural area); whole discal surface appearing glabrous except for few short, hairlike setae adjacent to notopleural sutures; surface of posterior lobe dull-shiny, lateral areas smooth, median area finely transversely wrinkled; proepisterna mostly with shallow, parallel wrinkles on juxtanotopleural area, with scattered hairlike setae in male, while with only few setae on ventral area in female; prosternum and mesosternum with long, erect, hairlike setae; metasternum with much sparser setae, partly glabrous; mesepisterna smooth, nearly glabrous, with indistinct anterodorsal impression (in both sexes); metepisterna glabrous.

Elytra ( Figs 9–12 ) elongate, length 6.30–7.20 mm long, posthumeral lateral bulges moderate in both sexes, outer margins only moderately dilated towards arcuate angles of anteapical convexity in male, slightly more distinctly dilated in female, then narrowed towards apices; apex in male with small but thorn-like external tooth and right-angled inner tooth, shallowly emarginated towards small, right-angled sutural spine; apex in female with small, blunt external tooth and large, notably protruding, subacute inner tooth; elytral surface matt-shiny, regularly convex, with small but distinct basomedian convexity formed by notably deep discal impression, then regularly convex on elytral disc; surface sculpture consisting of mostly large and deep punctures which are larger, deepest and anastomosing in chains on basodiscal convexity (less often anastomosing in male), more spaced and sparser within posterior part of discal impression, again very large on sublateral and lateral areas of elytral disc (spaced and with wider intervals in male, markedly anastomosing in chains in female), while almost effaced on large juxtasutural area of elytral disc including shiny medial area of posterior declivity (in female posterior declivity and also lateral areas of anteapical convexity almost smooth); also elytral base and anterior-humeral areas smooth and shiny; setal vesture regular, consisting of rather short, brightly white ornamental setae, obliquely directed posteriad; sparse hairlike setae present on humeral areas only.

Abdomen. Ventrites black, smooth, surface sparsely covered with white appressed microtrichia and with hairlike sensory setae at ventrites margins.

Legs ( Figs 1–2 ) notably long; coxae black with brownish apices; pro- and mesotrochanters with brownish tinge, metatrochanters shiny black, glabrous; femora black with bright yellow-testaceous apical area; tibiae black, their basal quarter to third yellow-testaceous; tarsi blackish, longer in male; male protarsi with third tarsomere markedly more dilated; claws black-brown; setal vesture consisting of whitish microtrichia which are very sparse on pro- and mesofemora; metafemora glabrous; protibiae with sparse whitish microtrichia; mesotibiae with denser, whitish microtrichia (as usual densest on apical third), laterally mixed with sparse, mostly darker bristles; metatibiae with much sparser microtrichia and only scattered lateral bristles; tarsi covered with rather dense white microsetae (male protarsi with usual lateral setose pad).

Aedeagus ( Fig. 3 ) 2.40 mm long, 0.45 mm wide, apical half almost straight and widest in middle, then conically constricted towards dorsad-hooked apex; basal half almost boomerang-bent (parameres were removed).

Etymology. The name of the new species is derived from the Mahimborondro protected area.

Distribution and ecology ( Figs 13–16 ). Pogonostoma (P.) mahimborondrense Moravec & Wiesner sp. nov. is known only from its type locality in the Mahimborondro protected area in Northern Highlands (administratively Sofia Region of northwestern Madagascar). The landscape includes still intact forest with flora containing typical species endemic to the Sambirano Domain (Goodman et. al. 2018), although the forest of Northern Highlands has prevailingly montane character.

The new species was discovered in the course of fieldwork in the western part of Mahimborondro over the course of an expedition 29 January–14 February 2019 which was also attended by the third author of the present paper. The only known male and female of the new species were found at an altitude of 1586–1616 m. The coordinates of the holotype locality show the vicinity of Bekavahy, those of the allotype point towards lake Matsabory Iadan’I Saza, both situated east of the Bemanevika humid zone boundary-line (see Mittermeier et al. (2021) and the maps Figs 15–16 ); the area is situated about 28 km north of the town of Bealanana (lying outside the protected area).

The male holotype was caught in a low forest floor. The beetle was crawling over the leaf litter on the ground near the base of a small moss-covered tree (Brett Gardner pers. com.).

The female allotype was encountered during a hike towards an intermediary camp at the lake of Matsabory Iadan’I Saza ( Figs 13–14 ). It was found in a small patch of wet forest on a small tree (about 40 cm in diameter) with almost smooth, bare bark (Dan Slootmaekers pers. com.).

Remarks (to the topography and research history). The protected area of Mahimborondro (officially Réserve de Ressources Naturelles de Mahimborondro) is located in the Northern Highlands (Sofia Region, northwestern Madagascar). It forms a corridor that links the protected area of Bemanevika (officially Paysage Harmonieux Protégé de Bemanevika) to the Tsaratanana Massif (Réserve Naturelle Intégrale de Tsaratanàna), and together with these forms part of northwestern Madagascar’s largest protected landscape – Complexe des Aires Protégées d’Ambohimirahavavy–Marivorahona (CAPAM) ( Goodman et al. 2018, Mittermeier et al. 2021).

The topography, geology, pedology and ecosystems of Bemanevika and Ambondrona (as part of the region Ankaizinana) with maps of the ecosystems of the Sofia Region, were previously described in detail by Ségalen & Tercinier (1951), those of Mahimborondro recently by Goodman et al. (2018). The landscape was given protected area status in April 2015 and is presently managed by The Peregrine Fund Madagascar ( Goodman et al. 2018, Mittermeier et al. 2021). This recently designated protected area has been only scarcely surveyed for tiger beetles. Nevertheless, although Mahimborondro or Bemanevika were mentioned neither by historical entomologists such as Horn (1934), Olsoufieff (1934), Jeannel (1946) and Viette (1961), nor by more recent ones (such as Andriamampianina et al. 2001), some historical specimens recorded from Bealanana (such as by Horn, 1934) or labelled “Bealanana” (the neighbouring town south of Bemanevika but outside the protected area) might have been collected in this quite recently established protected area. This includes Pogonostoma (Bathypogonum) levigatum lucens Rivalier, 1970 , but more Pogonostoma species and a number of taxa of other genera are known from the neighbouring Tsaratanana Massif (see Moravec 2002, 2007, 2010, 2022). Nevertheless, as mentioned above, the area including Bemanevika was also treated in the past (as a part of the Ankaizinana region), yet still within the large area of Bealanana ( Ségalen & Tercinier 1951, Map. 1).

Following fieldworks were conducted recently in Mahimborondro during the two above-mentioned expeditions. Results of the ornithological survey were published in Mittermeier et al. (2021); longhorns were studied by Bouyer et al. (2021); spiders by Jocqué & Jocque (2021) and dragonflies by Jocque et al. (2020).

Figures

FIGURES 1–6. Pogonostoma (P.) mahimborondrense sp. nov., from type locality, deposited in IRSNB). 1–2—habitus: 1—♂, 11 mm, HT; 2—♀, 12.6 mm, AT; 3—male aedeagus; 4—mandibles, ♂, HT; 5–6—labrum: 5—♂, HT; 6—♀, AT. Bars = 1 mm.

FIGURES 7–12. Pogonostoma (P.) mahimborondrense sp. nov., from type locality, deposited in IRSNB). 7–8—pronotum: 7—♂, HT; 8—♀, AT; 9–12—elytra: 9—♂, HT; 10—♀, AT; 11–12—elytral apices: 11—♂, HT; 12—♀, AT. Bars = 1 mm.

FIGURES 13–14. Pogonostoma (P.) mahimborondrense sp. nov. 13—Mahimborondro protected area: overall view near the Matsabory Iadan’I Saza lake. Image credit: Dan Slootmaekers. 14—forest near the collecting site of the allotype. Image credit: Brett Gardner.

FIGURES 15–16. Pogonostoma (P.) mahimborondrense sp. nov. 15—collecting sites of the two type specimens. Adopted and modified from a map available from BING satellite info – Microsoft product screen shot(s), reprinted with permission from Microsoft Corporation. 16—Map of locations surveyed in the Mahimborondro protected area. Reprinted from Mittermeier et al. (2021) (map source and copyright at the bottom of the map).