Cryptolarynx variabilis Haran, 2023

Haran, Julien M., Marvaldi, Adriana E., Benoit, Laure, Oberlander, Kenneth, Stals, Riaan & Oberprieler, Rolf G., 2023, Revision of the enigmatic South African Cryptolaryngini (Coleoptera, Curculionidae), with description of a new genus and twenty-two new species, European Journal of Taxonomy 877 (1), pp. 1-89 : 34-75

9. Cryptolarynx variabilis Haran sp. nov.

urn:lsid:zoobank.org:act:CABBADE9-B99D-481E-A5EE-ACFA0FF97187

Figs 1I , 2I , 3I , 4I , 5I , 6I–N , 8E

Differential diagnosis

Cryptolarynx variabilis sp. nov. is most similar to C. carinatus sp. nov., see the Differential diagnosis and Remarks sections under that species for diagnostic characters and genetic distances.

Etymology

The species name variabilis refers to the substantial morphological variation encountered in this species in terms of size, body ratios and elytral pattern. The specific epithet is an adjective in the masculine form.

Material examined

Holotype REPUBLIC OF SOUTH AFRICA • ♂; “ REPUBLIC OF SOUTH AFRICA. Western Cape Province, Stellenbosch. 20.vii.2018. J. Haran leg.” “ 33.949° S 18.876° E, sweeping of Oxalis pes-caprae . JHAR01185_0101. Cirad-CBGP coll.” “Holotype. Cryptolarynx variabilis . Haran 2023”; SAMC.

Paratypes REPUBLIC OF SOUTH AFRICA – Western Cape • 2 ♀♀; same collection data as for holotype; SAMC • 3 ♂♂, 2 ♀♀; same collection data as for holotype; MLP • 3 ♂♂, 2 ♀♀, 10 specs (preserved in ethanol); same collection data as for holotype; CBGP • 1 ♂, 1 ♀, 3 specs (preserved in ethanol); Stellenbosch, Paradyskloof ; 33.965° S, 18.877° E; 26 Jul. 2018; J. Haran leg.; at base of Oxalis purpurea ; JHAR01215; CBGP • 1 ♂; Stellenbosch ; 33.948° S, 18.879° E; 6 Aug. 2018; J. Haran leg.; Oxalis lanata ; JHAR01235-0102; CBGP • 1 ♀; Stellenbosch, Jan Marais Nature Reserve ; 33.931° S, 18.877° E; 15 Oct. 2019; R. Borovec leg.; sifting under Oxalis sp. in forest margin; FFWS • 1 ♂; Stellenbosch area, Koopmanskloof Nature Reserve ; 33.897° S, 18.769° E; Jul. 2014; A. Stander leg.; D-vac sampling; JHAR01245; CBGP • 1 ♂, 3 specs (preserved in ethanol); Stellenbosch ; 33.942° S, 18.873° E; 9 Aug. 2018; J. Haran leg.; Oxalis lanata ; JHAR01247; CBGP • 4 specs (preserved in ethanol); Stellenbosch ; 33.941° S, 18.872° E; 17 Aug. 2018; J. Haran leg.; Oxalis lanata ; JHAR01363; CBGP • 1 ♂, 17 specs (preserved in ethanol); Stellenbosch ; 33.949° S, 18.876° E; 3 Sep. 2018; J. Haran leg.; Oxalis pes-caprae ; JHAR01479; CBGP • 1 ♂, 7 specs (preserved in ethanol); Stellenbosch, Jan Marais Nature Reserve ; 33.930° S, 18.875° E; 13 Sep. 2018; J. Haran leg.; at base of Oxalis purpurea ; JHAR01497; CBGP • 1 ♂, 2 specs (preserved in ethanol); Franschhoek Pass ; 33.904° S, 19.157° E; 15 Sep. 2018; J. Haran leg.; JHAR01499; CBGP • 2 specs (preserved in ethanol); Pniel, Boschendal Estate ; 33.891° S, 18.980° E; 16 Aug. 2019; J. Haran leg.; at base of Oxalis spp. ; JHAR02564; CBGP • 4 specs (preserved in ethanol); Somerset West, Helderberg Nature Reserve ; 34.061° S, 18.874° E; 14 Oct. 2019; J. Haran leg.; at base of Oxalis purpurea ; JHAR02586; CBGP • 3 specs (preserved in ethanol); same collection data as for preceding; at base of Oxalis lanata ; JHAR02588; CBGP • 1 ♂; Somerset West ; [34.07° S, 18.84° E]; Nov.–Dec. 1927; A.J. Hesse; SAM-COL-A051992; SAMC .

Description (♂)

MEASUREMENTS. Body length 2.2–4.0 mm.

COLOUR AND VESTITURE. Body integument black, scapes and tarsi reddish. Dorsal vestiture (pronotum + elytra) consisting of overlapping, recumbent, parallel-sided clothing scales, 2–3× as long as wide, truncate or rounded at apex; colour of scales varying from greyish to pale brown to black; pale scales concentrated in two longitudinal stripes on pronotum and on elytral interstriae 4, white scales forming a pair of spots surrounded by black scales at apical ⅔ of elytra; scales of striae recumbent, in lateral view not distinct from rest of vestiture.

HEAD. Forehead as wide as epifrons near antennal insertions, as wide as width of an eye, scales recumbent. Eyes convex, in dorsal view slightly exceeding outline of head, surrounded by a ring of short pale scales, on forehead directed towards occiput; distance between eye and scrobe slightly smaller than width of antennal club. Epifrons with distance between antennal insertions 0.75 × length of scape, scales at least 2× as long as wide, recumbent, not contiguous. Frons with pairs of erect setae laterally. Epistome without median seta. Antennal funicles with segment 1 elongate; 2 half as long as 1, at most 2× as long as wide; 3–4 globular, isodiametric, compressed, slightly angular on inside; 5–7 globular, isodiametric; 7 sometimes wider than long.

PRONOTUM. Transverse (W:L ratio 1.5–1.7), widest near midlength, sides arcuate; width of apex ⅔ × width of base.

ELYTRA. Broadly ovate, slightly wider than long (W:L ratio 1.1), sides convex, widest near midlength.

LEGS. Protibiae with outer margin straight, inner margin almost straight; metatibiae with apical mucro and inner setal fringe, setae shorter than segment 5 of metatarsus; metatibiae proximally with inner carina set off at an angle of ca 20° to outer margin. Tarsi with segment 2 wider than long.

ABDOMEN. Ventrite 1 concave medially, impression with long setae and little scale cover; ventrites 1–4 with creamy-white or greyish plumose scales, not concealing integument, intermixed with long suberect setae, each apically bifid.

TERMINALIA. Body of penis elongate (W:L ratio 0.4), as long as temones, sides subparallel, converging close to apex; curvature in profile weak and regular, dorsoventrally narrowed before apex. Copulatory sclerite serrate. Parameroid lobes separate, divided by modest median notch, each lobe broad, bearing a series of long setae directed apicad. Spiculum gastrale with basal arms long, right arm angled in midlength.

Sexual dimorphism

The sexes can be distinguished by the shape of ventrite 1 (in males concave with long setae divided from their bases, in females flat or slightly convex with short setae not or only slightly divided at their apices).

Life history

The larvae of C. variabilis sp. nov. develop in the bulbs of various species of Oxalis ( O. pes-caprae L., O. purpurea and O. lanata ); see Life history and Morphology of immature stages subsections of the Results section for details. Adults of the species were collected between July and October. The heat tolerance of this species was assessed in a comparative study of weevils associated with fire-prone ecosystems ( Javal et al. 2022). Adults of C. variabilis were found to survive temperatures above 50°C, which is rare for arthropods, especially in small insects. This tolerance was hypothesized to be an adaptation for the survival of the larvae and teneral adults when enclosed in the bulbs during summer, a few centimetres below the surface of the ground.

Distribution

Based on the samples examined, C. variabilis sp. nov. seems to be restricted to the western slope of the Hottentots Holland Mountains range, from the Franschhoek Pass to Somerset West ( Fig. 13 ).

Remarks

Intraspecific genetic distances among C. variabilis sp. nov. specimens were found to span up to 7.0% for COI (JHAR02563 / JHAR02586) and 1.9% for EF1 (JHAR01499 / JHAR01235), suggesting that several lineages in the process of differentiation may exist in the species as treated here.

Morphology of immature stages

Cryptolarynx variabilis Haran sp. nov.

Material examined

Eggs

REPUBLIC OF SOUTH AFRICA – Western Cape • 2 specs (preserved in ethanol); Stellenbosch ; 33.949° S, 18.876° E; 20 Jul. 2018; J. Haran leg.; eggs deposited by reared adults collected on Oxalis pes-caprae ; JHAR01185; CBGP. Determined by association with adults .

Larvae

REPUBLIC OF SOUTH AFRICA – Western Cape • 2 specs in second and third instar; Stellenbosch ; 33.949° S, 18.876° E; 20 Jul. 2018; J. Haran leg.; in bulbs of Oxalis pes-caprae ; JHAR01185; (larvae initially preserved in ethanol; then dissected and slide-mounted in Euparal (as in May 1993) for examination under compound microscope) MLPA (preserved in ethanol) • 1 spec. of undetermined instar; same collection data as for preceding; CBGP • 1 spec. in last instar (larva initially preserved in ethanol; then dissected and slide-mounted in Euparal (as in May 1993) for examination under compound microscope); Stellenbosch, Jan Marais Nature Reserve ; 33.930° S, 18.875° E; 13 Sep. 2018; J. Haran leg.; in bulb of Oxalis purpurea ; JHAR01497; MLP. Determined by association with adults .

Pupa

REPUBLIC OF SOUTH AFRICA – Western Cape • 1 spec. (preserved in ethanol); Stellenbosch ; 33.942° S, 18.873° E; 9 Aug. 2018; J. Haran leg.; in bulb of Oxalis lanata ; JHAR01247; CBGP. Determined by association with adults.

Descriptions

Egg

Length 0.8–1.0 mm; width 0.2–0.3 mm, widest near midlength. Slightly curved. Yellow.

Larva ( Figs 9A–B , 10A–I )

MEASUREMENTS. Maximum body length 4.62 mm; head width 0.55 mm.

HABITUS. Body very robust, curved, widest at thorax and anterior abdominal segments; setae pallid and inconspicuous, the longer setae slender, fine; cuticle with minute asperities; posterior third of head capsule in repose partially retracted into pronotum.

HEAD. Subcircular in outline, about as long as wide; posterior margin rounded, not emarginate. Epicranial line short, about 0.3 × length of head capsule. Frontal lines and endocarina absent. Hypopharyngeal bracon hyaline, without maculae. Postoccipital margin simple, without condyles. Cranial setae well developed, in modal numbers: fs3, 4, 5 long, fs1, 2 shorter, fs3 placed outward of fs4 and behind fs5, des1, 2, 3, 4, 5, well developed, des4 shorter, pes1–4 minute; epicranial sensillum present, close to des2 and pes4; les1, 2 long; vcs1, 2 long.

STEMMATA. Present as two pigmented dark spots, anterior stemma larger than posterior one.

ANTENNAE. Situated on dorso-anterior margin of head; membranous basal segment bearing sensorium and eight smaller sensilla externally; sensorium broadly conical, about isodiametric or slightly longer than wide, circular in apical view.

CLYPEUS. Pigmented at base; cls1, 2 well developed; sensillum closer to cls1.

LABRUM. Transverse, completely pigmented, anterior margin evenly rounded; labral setae lms1 well developed; single basal sensillum present, median (lateral) sensilla absent; labral rods (seen on epipharyngeal side) subparallel, rather short, acute at apices.

EPIPHARYNX. With three als; ams1 conspicuous; mes1, 2 between labral rods, mes1 pair slightly less apart than mes2 pair.

MANDIBLES. Bidentate at apex, with obtuse tooth on cutting edge; transversely rugose on exterior lateral surface; mds1, 2 aligned transversely.

MAXILLAE. Each stipe with 1 seta at base, 2 palpiferal setae and 1 minute seta plus sensillum near base of mala; maxillary malae with 4 vms, median 2 smaller, and with 6 elongated dms in a row; maxillary palps 2-segmented, 1 seta on basal segment, none on distal segment.

LABIUM. Postmentum with pms1 pair more widely apart than pms2, 3 pairs; premental sclerite hardly distinct, its posterior extension subtriangular, posterior margin V-shaped, anterior extension indistinct; labial palps 1-segmented; ligula wide.

THORAX. Spiracles placed on pronothorax, oval, annular, without airtubes. Pronotum pigmented, not divided by median line, with 9 setae. Meso- and metathorax with 1 prs and 4 pds. Pedal area with 4 clearly distinct setae (t, u, v and w); the longest (v and w) placed on a lobe slightly distinct in the pedal area; some minute additional setae present (e.g., v´).

ABDOMEN. Spiracles of AI–VIII placed laterally, of similar size as thoracic spiracle, subcircular, without airtubes. Segments AI–VII with 3 dorsal folds, prodorsum and postdorsum both similarly prominent. AVIII with prodorsum and postdorsum distinct.AIX with dorsum somewhat expanded over AX (in mature larva). AX with anus subterminal; lateral anal lobes and dorsal anal lobe larger than ventral anal lobe.

Remarks

The smaller larva examined ( Fig. 9B ) may correspond to the second instar (body length 2.40 mm; head width 0.39 mm). It agrees with the last-instar larva in the characters described above ( Fig. 10A–I ), including the spiracles. Differences between early- and later-instar larvae involve relative dimension of structures, with the head (in relation to body), the antennae and stemmata being relatively larger in earlier instars, and the pigmentation and level of sclerotisation of body areas tend to increase in successive instars.

Pupa ( Fig. 11A–C )

Colour white, cuticle smooth. Setae (given for one side of body) inconspicuous, pallid, placed on small tubercles on head (with 1 vs, 1 sos; rostrum with 2 brs; without setae on mandibular theca) and pronotum (with 2 aps, 3 lps, 2 bps, and 3 dps). Rostrum reaching procoxae. Pronotum 1.3× as wide as long, rounded laterally, tapering anteriorly. Mesonotum 1.5× as long as metanotum. Primary pterothecae (elytral sheaths) well developed, covering hindlegs (when folded onto body, as in Fig. 6L ); secondary pterothecae absent (adult without hindwings). Femora without apical setae. Abdominal segments I–IV of subequal width; segments V–VIII tapered gradually towards terminal IX, the latter with posterior processes (“pupal urogomphi”) small, pointed at sclerotised apex.

Figures

Fig. 1 (Part I) (next page). Habitus of males of species of Cryptolarynx Van Schalkwyk, 1966 (dorsal view). A. C. vitis (Marshall, 1957). B. C. subglaber Haran sp. nov. C. C. squamulatus Haran sp. nov. D. C. muellerae Haran sp. nov. E. C. hirtulus Haran sp. nov. F. C. robustus Haran sp. nov. G. C. namaquanus Haran sp. nov. H. C. carinatus Haran sp. nov. I. C. variabilis Haran sp. nov. J. C. estriatus (Marshall, 1957). K. C. pyrophilus Haran sp. nov. L. C. pilipes Haran sp. nov. Not to scale.

Fig. 2 (Part I) (next page). Male genitalia of species of Cryptolarynx Van Schalkwyk, 1966. Penis in dorsal and lateral view (left), tegmen in dorsal view (middle) and details of apex of a parameroid lobe and spiculum gastrale in dorsal view (right). A. C. vitis (Marshall, 1957). B. C. subglaber Haran sp. nov. C. C. squamulatus Haran sp. nov. D. C. muellerae Haran sp. nov. E. C. hirtulus Haran sp. nov. F. C. robustus Haran sp. nov. G. C. namaquanus Haran sp. nov. H. C. carinatus Haran sp. nov. I. C. variabilis Haran sp. nov. J. C. estriatus (Marshall, 1957). K. C. pyrophilus Haran sp. nov. L. C. pilipes Haran sp. nov. Not to scale.

Fig. 3 (Part I) (next page). Habitus of males of species of Cryptolarynx Van Schalkwyk, 1966 (lateral view). A. C. vitis (Marshall, 1957). B. C. subglaber Haran sp. nov. C. C. squamulatus Haran sp. nov. D. C. muellerae Haran sp. nov. E. C. hirtulus Haran sp. nov. F. C. robustus Haran sp. nov. G. C. namaquanus Haran sp. nov. H. C. carinatus Haran sp. nov. I. C. variabilis Haran sp. nov. J. C. estriatus (Marshall, 1957). K. C. pyrophilus Haran sp. nov. L. C. pilipes Haran sp. nov. Not to scale.

Fig. 4 (Part I) (next page). Head of males of species of Cryptolarynx Van Schalkwyk, 1966. A. C. vitis (Marshall, 1957). B. C. subglaber Haran sp. nov. C. C. squamulatus Haran sp. nov. D. C. muellerae Haran sp. nov. E. C. hirtulus Haran sp. nov. F. C. robustus Haran sp. nov. G. C. namaquanus Haran sp. nov. H. C. carinatus Haran sp. nov. I. C. variabilis Haran sp. nov. J. C. estriatus (Marshall, 1957). K. C. pyrophilus Haran sp. nov. L. C. pilipes Haran sp. nov. Not to scale.

Fig. 5 (Part I). Ventrites of males of species of Cryptolarynx Van Schalkwyk, 1966. A. C. vitis (Marshall, 1957). B. C. subglaber Haran sp. nov. C. C. squamulatus Haran sp. nov. D. C. muellerae Haran sp. nov. E. C. hirtulus Haran sp. nov. F. C. robustus Haran sp. nov. G. C. namaquanus Haran sp. nov. H. C. carinatus Haran sp. nov. I. C. variabilis Haran sp. nov. J. C. estriatus (Marshall, 1957), with details of a cuticular carina (white arrows). K. C. pyrophilus Haran sp. nov. L. C. pilipes Haran sp. nov. Not to scale.

Fig. 6 (preceding page). Habitus in natura, host plants and biotopes of species of Cryptolarynx Van Schalkwyk, 1966 (part 1). A. C. vitis (Marshall, 1957), Tygerberg Nature Reserve (JHAR02568). B. Dark variants of C. vitis, Grootbos Private Nature Reserve (JHAR01592). C. Biotope and stands of Oxalis glabra Thunb. hosting C. vitis (JHAR01488). D. Habitus of C. hirtulus Haran sp. nov., Worcester (JHAR02356). E. Adult of C. hirtulus Haran sp. nov. under a stone, in its gallery after emergence from a bulb of Oxalis obtusa Jacq., near Touwsrivier (JHAR02444). F. Biotope of C. hirtulus Haran sp. nov. with stands of Oxalis obtusa, near Touwsrivier. G. Habitus of C. carinatus Haran sp. nov., Rondebosch Common (JHAR02336). H. Oxalis purpurea L., host of C. carinatus Haran sp. nov., Rondebosch Common. I. Corm of Oxalis pes-caprae L. with emergence hole of C. variabilis Haran sp. nov. J. Habitus of C. variabilis Haran sp. nov., Stellenbosch (JHAR01185). K. Larva of C. variabilis Haran sp. nov. in bulb of Oxalis purpurea, Stellenbosch (JHAR01215). L. Pupa of C. variabilis Haran sp. nov. in bulb of Oxalis lanata Thunb., Stellenbosch (JHAR01247). M. Teneral adult of C. variabilis Haran sp. nov. in bulb of Oxalis pes-caprae, Stellenbosch (JHAR01185). N. Oxalis pes-caprae, host of C. variabilis Haran sp. nov., Stellenbosch. O–P. Oxalis sp. host and biotope of C. armatus Haran sp. nov., near Nieuwoudtville (JHAR02519).

Fig. 8 (next page). Structural details and measurements of Cryptolaryngini Van Schalkwyk, 1966. A. Cryptolarynx spinicornis Haran sp. nov., cephalic view, arrows indicating width of forehead (top) and of epifrons (bottom). B. Head of C. pyrophilus Haran sp. nov., lateral view, arrows indicating distance between eye and scrobe. C. Head of C. pyrophilus Haran sp. nov., in cephalic view, arrows showing prothoracic scales near eyes (top), position of scape when antennae in repose (middle) and position of clubs near procoxae when in repose (bottom). D. C. namaquanus Haran sp. nov., dorsal view, arrows indicate length and width dimensions of pronotum and elytra as measured.E. Metafemora and metatarsus of C. variabilis Haran sp. nov. (left) and C. carinatus Haran sp. nov. (right), arrows indicating position of proximal inner carina in latter species (highlighted with a white line in C. variabilis Haran sp. nov.) and short apical mucro. F. Metatarsus of Hadrocryptolarynx major Haran gen. et sp. nov., arrow indicating elongate segment 2 (longer than wide). G. Hindleg of C. vitis (Marshall, 1957), arrow indicating apical mucro. H. Antenna of C. spinicornis Haran sp. nov., arrows pointing at inner tooth of funicle segments 2 and 4. I. Protibia of C. armatus Haran sp. nov., arrow pointing at inner preapical expansion proximally of mucro. J. Penis of C. oberprieleri Haran sp. nov., dorsal view, black arrows indicating length of penis body and temones and white arrows indicating width of penis body as measured; bottom arrow indicating copulatory sclerite. K. Ovipositor, Crypolarynx variabilis Haran sp. nov. L. Sternite VIII, same species. M. Spermatheca, same species. N. Ovipositor, Hadrocryptolarynx major Haran gen. et sp. nov. O. Sternite VIII, same species. P. Spermatheca, same species. Q. Right maxilla, same species. Not to scale.

Fig. 13. Distribution maps of species of Cryptolarynx Van Schalkwyk, 1966 and Hadrocryptolarynx Haran gen. nov.

Fig. 9. Habitus of larvae of Cryptolarynx variabilis sp. nov., lateral view. A. Last-instar larva (TI, pronotum; AIV, fourth abdominal segment). B. Early second-instar larva (AII, second abdominal segment). Scale bars = 1.0 mm.

Fig. 10. Larva of Cryptolarynx variabilis sp. nov., morphological structures (drawn from second-instar larva, except A and G from last-instar larva). A. Head capsule, dorsal view (fs, frontal setae; des, dorsal epicranial setae; pes, posterior epicranial setae; les, lateral epicranial setae). B. Clypeus and labrum, including a portion of head with antennae. C. Epipharynx. D. Mandible. E. Maxilla and labium, ventral view. F. Maxilla, dorsal view. G. Spiracles of thorax and abdominal segments I, IV and VIII, last-instar larva. H. Spiracles of thorax and abdominal segment VIII, second-instar larva. I. Pro- and mesothorax, ventral view (one half), showing pedal areas with setae named in the former. Scale bars = 0.1 mm.

Fig. 11. Habitus of pupa of Cryptolarynx variabilis sp. nov., dorsal (A), ventral (B) and lateral (C) views. Scale bar = 1 mm.