Phlyctinus xerophilus Haran, 2020

Haran, Julien M., Hansen, Steffan, Benoit, Laure & Addison, Pia, 2020, Description of five new species in the genus Phlyctinus Schoenherr (Coleoptera, Curculionidae): a first step in deciphering the P. callosus complex, European Journal of Taxonomy 669 (669), pp. 1-29 : 13-16

Phlyctinus xerophilus Haran sp. nov.

urn:lsid:zoobank.org:act:4B53AE34-6D14-4365-BD47-762A6596ED1B

Figs 1C , 2C , 3C , 4B

Etymology

This species is named in reference to its known distribution range, which comprises dryer and warmer inland habitats than those of the other species of the genus.

Material examined

Holotype

REPUBLIC OF SOUTH AFRICA • ♂; Western Cape province, De Doorns ; 33º30.577ʹ S, 19º31.799ʹ E; 23 Jul. 2019; S. Hansen leg.; at base of Plantago lanceolata ; CBGP code JHAR02442; SAMC.

Paratypes

REPUBLIC OF SOUTH AFRICA – Western Cape province • 1 ♀; same collection data as for holotype; SAMC • 1 ♂, 1 ♀; Hex River valley, Idle Winds farm; 33º30.832ʹ S, 19º34.278ʹ E; 30 Jan. 2019; S. Hansen leg.; under vine bark in table grape vineyard; CBGP code JHAR02173; SUIC • 4 ♂♂, 3 ♀♀; same locality as for preceding; 10 Dec. 2019; S. Hansen and J. Haran leg.; at base of table grape vineyard; CBGP code JHAR03097; CBGP • 3 ♂♂, 1 ♀; De Doorns ; 33.28º S, 19.43º E; 18 Nov. 1982; R.G. Oberprieler and C.D. Eardley leg.; SANC • 2 ♂♂, 1 ♀; Robertson ; 33.28º S, 19.53º E; 18 Nov. 1983; A. Schwartz; SANC .

Description

BODY LENGTH. 7.0–8.0 mm.

COLOUR. Body integument dark red, head and prothorax darker, usually black; vestiture of elytra consisting of a dense cover of small, elliptic scales, slightly longer than wide, not completely concealing integument; scales pale brown with spots of pearly green scales generally forming a transverse band in apical ⅔ of elytra, a short strip at base on 3 rd interstria, longitudinal bands on basal half of sides of prothorax and a few dots on apical margin of prothorax.

HEAD. Rostrum longer than wide (w/l ratio: 0.80) in both sexes, base as wide as apex, sides slightly concave near middle of length; epifrons as wide at base as width of eye, at base narrower than distance between eyes, sides widening from base to apex, upper face with a longitudinal carina extending from basal transverse groove to nasal plate, visible through scales; nasal plate V-shaped, reaching level of antennal insertion basally, bare of scales, with short setae inserted in scattered punctures and 3 pairs of long setae apically near insertion of mandibles (2 short and 1 very long); antennal scrobes slightly curved in lateral view, directed to middle of eye, separated from it by a strip of scales as wide as diameter of eyes; mandibles trisetose, bare of scales. Forehead with a short longitudinal furrow between eyes, scales and setae arranged centripetally towards a point below base of eyes. Eyes protruding, surface almost conical in dorsal view. Antennae slender, scape 1.25 × as long as funicle, slightly bisinuate, subclavate at apex, exceeding anterior margin of prothorax in repose; funicle with segments 1–2 elongate, 1 shorter (0.70 ×) than 2, segments 3–7 longer than wide, conical, 3–5 shortening apicad, 5–6 widening apicad; club spindle-shaped, segment 1 longer than 2, margins slightly sinuous.

PROTHORAX. Slightly wider than long (w/l ratio: 1.20), widest slightly before middle of length, apical margin 0.75 × as wide as base, sides rounded, apical half slightly concave; integument forming a dense cover of elongate granules orientated parallel to median carina and two slight depressions on each side of median carina; median carina raised, smooth and shiny, not reaching apical and basal margins of prothorax.

ELYTRA. Sides slightly convex, widest before middle of length (w/l ratio: 0.73–0.77), integument smooth, shiny, finely punctate, interstriae raised, 2–4 × as wide as width of striae in basal half; large declivital callosities present on apical ¼ of interstriae 3, 5 and 7 and smaller ones on 2, 4, 6 and 8; each interstria with a series of semi-erect, elongate whitish scales, condensed on callosities.

ABDOMEN. Underside with pearly green or pearly brown scales, not concealing integument, more condensed on metanepisterna; ventrite 1 shorter than 2+ 3+4, slightly convex in middle (♀) or concave with erect setae slightly shorter than claws (♂), ventrite 5 longer than 3+4, with erect setae in middle and near apex and a smooth longitudinal carina (♀) or with large cavity extending on apical ⅔, with long erect setae condensed on margins and along a longitudinal line at bottom of cavity (♂) ( Fig. 3C ).

LEGS. Femora clavate, unarmed, with a ring of more condensed pale scales near middle; tibiae straight, unarmed, slightly bisinuate on ventral side; claws simple, free, equal in length.

GENITALIA. Body of penis short, 0.5 × as long as apodemes, sides bisinuate, widest above middle of length, converging from there towards apex, apex pointed (w/l ratio: 0.50), in lateral view curvature weak and regular ( Fig. 2C ); endophallus with a sclerotised plate forming a square angle below base of body of penis; copulatory sclerite with left arm as long as body, strongly curved inwards, not bearing setae; comb of right arm with setae converging; right area of body wider than left area.

Sexual dimorphism

Males may be distinguished externally from females by the cavity and setae on ventrite 5.

Life history

Adults of P. xerophilus sp. nov. have been found at the base of vines and Plantago lanceolata plants in table grape vineyards ( Fig. 4B ). The host plants of the larvae are unknown. Adults were collected in January, July, September and December.

Distribution

As currently known, this species seems to occur naturally in the region of Robertson and the Hex River valley.

Remarks

Phlyctinus xerophilus sp. nov. is similar to P. callosus but differs from it by the erect setae along the median line of the cavity of ventrite 5 of the males ( Fig. 3C ). It is also slightly larger, more elongate and has larger elytral tubercles on the declivity than P. callosus . Females of the two species are difficult to distinguish morphologically. As knowledge stands, there seems to be only a small overlap between their distribution ranges and therefore the geographical origin of specimens can assist in their identification. The two species can also be distinguished using their COI sequences, which show divergences ranging from 9.2 to 9.8%.

The sequencing of other specimens morphologically similar to P. xerophilus sp. nov. ( Table 1 ) showed that this species contains at least four mitochondrial lineages ( Fig. 5 ) found in populations from distinct localities. Uncorrected p-distances between all these lineages ranged from 5.5 and 8.5%. Preliminary observations made on series of specimens from these localities showed subtle morphological differences that suggest that this species could be a complex of closely related or cryptic species. A formal treatment of this complex has not been undertaken here due to limited fresh material available. It will be the focus of a future study. All specimens found to date run to P. xerophilus sp. nov. in the key provided. As knowledge stands, only the specimens described formally here as P. xerophilus sp. nov. are agricultural pests. Other specimens were found in natural or semi-natural habitats.

Figures

Fig. 1 (opposite page). Habitus of species of Phlyctinus Schoenherr, 1826 males (left) and females (right). A. P. callosus (Schoenherr, 1826). B. P. grootbosensis Haran sp. nov. C. P. xerophilus Haran sp. nov., holotype ♂. D. P. planithorax Haran sp. nov., holotype ♂. E. P. littoralis Haran sp. nov., holotype ♂. F. P. aloevorus Haran sp. nov., holotype ♂. Scale bars = 3 mm

Fig. 2. Penis of Phlyctinus Schoenherr, 1826, in dorsal (left) and lateral (right) view, and copulatory sclerite (top right). A. P. callosus (Schoenherr, 1826). B. P. grootbosensis Haran sp. nov. C. P. xerophilus Haran sp. nov., holotype ♂. D. P. planithorax Haran sp. nov., holotype ♂. E. P. littoralis Haran sp. nov., holotype ♂. F. P. aloevorus Haran sp. nov., holotype ♂. Scale bars = 500 µm. Copulatory sclerite not to scale.

Fig. 3 (opposite page). A–B. Ventrites of males of Phlyctinus Schoenherr, 1826 (left: ventrites 1–5, right: ventrite 5). A. P. callosus (Schoenherr, 1826). B. P. grootbosensis Haran sp. nov. C–D. Ventrite 5. C. P. xerophilus Haran sp. nov., holotype ♂. D. P. planithorax Haran sp. nov. E–F. Vestiture of basal right side of elytra. E. P. callosus (Schoenherr, 1826) (left). F. P. littoralis Haran sp. nov. Scale bars = 0.5 mm.

Fig. 4 (opposite page). Habitus in natura, host plants and biotopes of Phlyctinus Schoenherr, 1826 species. A. P. callosus (Schoenherr, 1826). B. P. xerophilus Haran sp. nov. C–D. P. grootbosensis Haran sp. nov. and its host plant, Osteospermum moniliferum L. E–F. P. planithorax Haran sp. nov. and its host plant, Hymenolepis crithmifolia (L.) Greuter. G–H. Biotope and host plant (Arctotis angustifolia L.) of P. littoralis Haran sp. nov. I–J. P. aloevorus Haran sp. nov. on its host plant, Aloe arborescens Mill., with details of feeding damage on floral peduncle

Fig. 5. PhyML tree of Phlyctinus Schoenherr, 1826 species inferred from mitochondrial Cytochrome oxidase I (COI, 658 base pairs). Bootstrap support values as obtained from 1000 replicates (*above 80, ** above 95). Specimens codes were shortened for representation: JHAR0 = J and _0101 = -1.