Rhynchitapion variiforme, Wanat, 2021
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Rhynchitapion variiforme sp. n.
Type material. Holotype ♂: a) RSA (E) KZN 1420 m / -29.4844 / 29.8992 / Wakefield Farm / 23.11.2019 C forest/leg. M. Wanat ( TMSA) [dissected, abdominal ventrites glued near specimen, hind wings glued to separate card below, genitalia in glycerol—microvial pinned under specimen] GoogleMaps . Paratypes (20 ♂ 26 ♀): R. S.A.: Limpopo: a) South Africa, Tvl / Ebenezer Dam vicinity/ 23.55S 29.58E / 1400 m; 16.i.1991 GoogleMaps / R. G. Oberprieler [-23.9167 / 29.9667] (1 ♂, SANC); a) South Africa, Tvl / D’Nyala Nat. Res. / Ellisras District / 23.45S 27.49E / xii.1987 GoogleMaps / B. Grobbelaar [-23.75/27.8167] (1 ♂, SANC). Mpumalanga: a) S.Afr., E. Transvaal / Berlin F. S., gorge/ 25.32 S – 30.44 E, b) 9.12.1986 GoogleMaps , E-Y: 2366/ intersept trap, 56 d./leg. Endrödy-Younga [-25.5333 / 30.7333] (1 ♀, TMSA); Mariepskop (summit), - 24.5517S / 30.8721E, 1900 m, mountain fynbos, 16.11.2012 GoogleMaps ; leg. M. Wanat (1 ♂, MWC), leg. P. Jałoszyński (2 ♂, MWC). KwaZu- lu-Natal: a) S Afr. Natal /W. Wittmer /1987, b) 11 km W Colenso /20.XI. Natal (1 ♀, SANC); a) S.Afr., S. Natal, Weza / lower Stinkwood for./ 30.34S- 29.43E, b) 20.11.1989 GoogleMaps , E-Y: 2701/beating in forest/ Endrödy & Klimaszew [ski], c) ex. for SEM/M. Wanat / 26-6-2014 / 3 [-30.5667 / 29.7167] (1 ♂, TMSA); same a) & b) labels (1 ♀, TMSA); a) S. Afr., S. Natal, Weza / Ingeni forest / 30.32 S- 29.41 E, b) 18.11.1989 GoogleMaps , E-Y: 2691/groundtraps, 10 days/ Endrödy & Klimaszew [ski], c) groundtrap with meat bait [-30.5333 / 29.6833] (1 ♀, TMSA); a) S. Afr., Natal Middld. / Karkloof for. 1300 m / 29.18 S – 30.13 E, b) 2.12.1989 GoogleMaps , E-Y: 2733/beating in forest/ Endrödy & Klimaszew [ski] [-29.30/30.2167] (1 ♀, TMSA); a) S. Africa ./ R.E. Turner. / Brit. Mus. /1927–62, b) Natal:/ Van Reenen,/ Drakensberg. / 23-26.i.1927 (1 ♀, BMNH) ; Karkloof Forest, Bushwillow Park , - 29.3178S / 30.2942E, 1200-1300 m alt., 6.11.2013 GoogleMaps , leg. R. Ruta (1 ♀, MWC); -29.3160 / 30.2939, 1200 m, forest trail along stream, 5.12.2019 GoogleMaps , leg. MW (2 ♂, MWC), 6.12.2019 , leg. MW (1 ♀, MWC); -29.3178 / 30.2957, 1180 m, Bushwillow Camp area & adjoining forest trail, 6.12.2019 GoogleMaps , leg. P. Jałoszyński (1 ♂ 1 ♀, MWC). Wakefield Farm , C[entral] forest, -29.4844 / 29.8992, 1420 m, 23.11.2019 GoogleMaps , leg. MW (1 ♂, MWC); 24.11.2019 , beating Celastraceae etc. (1 ♂ 1 ♀, MWC, TMSA). Eastern Cape: a) South Africa, CP/ Nico Malan Pass ,/ 5 km NE Seymour, 1400 m / 32.30S 26.50E / 25.xi.1988 GoogleMaps / B. Grobbelaar [-32.5/26.8333] (1 ♀, SANC); a) South Africa, C.P./ Grahamstown , 33.19S / 26.32E, 29.xi.1983 GoogleMaps / R. Oberprieler [-33.3167 / 26.5333] (2 ♀, SANC); a) South Africa, C.P./ Hogsback Mnt , 32.35S / 27.05E, 3.xii.1983 GoogleMaps / R. Oberprieler, b) collected off Cas- sine crocea [-32.5833 / 27.0833] (1 ♂, SANC); a) S. Afr.; Cape, Amatole / Isidenge For. St. , B1/ 32.41 S – 27.14 E, b) 17.11.1987 GoogleMaps , E-Y: 2521/beating indig. for./leg. Endrödy-Younga [-32.6833 / 27.2333] (1 ♀, TMSA); a) S. Africa GoogleMaps ./ R.E. Turner. / Brit. Mus. /1931–37, b) Cape Province:/ Somerset East. / 10-22.XII.1930. (1 ♂, BMNH) ; a) S. Africa./ R.E. Turner. / Brit. Mus. /1932–551, b) E. Cape Prov. / Katberg / 1-13.XI.1932. (1 ♂, BMNH) ; a) S. Africa./ R.E. Turner. / Brit. Mus. /1933–79, b) E. Cape Prov. / Katberg. / 4,000ft. / 1-15.I.1933. (1 ♀, BMNH) ; a) S. Africa./ R.E. Turner. / Brit. Mus. /1933–108, b) E. Cape Prov. / Katberg. / 15-30.I.1933. (1 ♂ 1 ♀, orig. preserved in copula, BMNH) ; a) RSA, S Eastern Cape / Komga , bushland/S 32°34.5’ E 27°56.6’/ 25.11.2017 , alt. 600 m / Petr Kresl leg., b) Collection / Petr Kresl / Spůle, Czech. Rep. /nr. Ap. 2240 [-32.575 / 27.9433] (1 ♀, PKC); Xholorha Forest , blue & yellow trails, - 32.5368S / 27.3647E, 940-1050 m, 17.11.2013 GoogleMaps , leg. MW (1 ♀, MWC); Ndwalane (N of), -31.5964 / 29.4626, 60-120 m, bush & forest, 29.11.2019 GoogleMaps , leg. MW (1 ♂ 1 ♀, MWC); Silaka Reserve , -31.6549 / 29.5051, 20-35 m alt., main rd (lower, to chalet 15), 1.12.2019 GoogleMaps , leg. MW (1 ♀, MWC). Western Cape: a) Leipoldtville /— Eland’s Bay /C. P./[back side] Mus. Exp. ,/ Nov. 1948 , b) SAM-COL-/A050708 [- 32.233°S, 18.483°E] (1 ♀, ISAM); a) South Africa, CP/ Bloukrans Pass,/ Tsitsikamma ,/ 33.57S 23.38E / 06.xii.1988 GoogleMaps / R. Oberprieler [-33.95/23.6333] (2 ♀, SANC); a) S Afr., Cape Prov. /W. Wittmer , b) Knysna /20. km W/ 6.XI.1988 (1 ♂, SANC) ; Tsitsikamma N.P.: Nature’s Valley , Grootk- loof trail, km 0-1.5, - 33.9678S / 23.5604E, 10-30 m alt.; 23.11.2013 GoogleMaps , beating, leg. MW (3 ♂ 1 ♀, MWC, TMSA); Harkerville, Perdekop trail, km 0-1, - 34.0477S / 23.2308E, 250 m, 25.11.2013 GoogleMaps , humid forest, beating, leg. MW (1 ♀, MWC); Wilderness N.P., Brownhooded Kingfisher trail, km 0-0.4, - 33.9834S / 22.6512E, 25 m, 29.11.2013 GoogleMaps , beating, leg. MW (1 ♀, MWC) .
Diagnosis. Despite of its extraordinary infraspecific variation, the species is easy to distinguish from two congeners by the dense and long, in part ruffled hair-like setae on the whole dorsal side of body and its appendices, partly black or blackish-brown coloration of integument (mainly the head with rostrum, legs and distal parts of antennae), and by many internal characters, e.g., penis with subrectangular apex, presence of characteristic inverted Vshaped sclerite in between the bar-like endophallic frena, or female spiculum ventrale having broad, anchor-shaped sternal plate and straight apodeme.
See also the key to Rhynchitapion species below.
Description. Body length 1.4–3.7 mm. Coloration of integument highly variable ( Figs. 1–6 View FIGURES 1–15 ). Rostrum, head and legs black, rarely dark testaceous or blackish-brown; antennae variably bi-colored, from only a part of scape to entire scape and funicle red-testaceous (then usually distal funicular joints partially darkened), club always dark; pronotum and body venter usually black, rarely variously lightened to testaceous; elytra most often orange-red with darkened extreme apex (as in the holotype), but they may be either fully red or black, or testaceous with blurred blackish median fleck, entirely black or with bluish reflection, or additionally with red spots around humeral calli. Protruding setae hair-like, prevailingly dark with admixed shorter light ones, mostly 3–4 × longer than breadth of elytral intervals, part of them ruffled; setosity dense, especially on elytra and pronotum; setae on elytral apex in part curved outward from suture.
Morphological indices (n=23): rl/pl: 0.95–1.20; rl/mxrw: 2.50–3.66; scl/msrw: 0.89–1.43; msrw/mtrw: 1.09–1.36; msrw/arw: ♂ 1.03–1.17 (M: 1.10), ♀ 0.96–1.11 (M: 1.03); msrw/minrw: 1.01–1.36; msrw/eyl: 0.74– 1.00; brl/eyl: 1.20–2.00; eyl/hl: 0.58–0.81; frw/mtrw: 1.17–1.73; hl/hw: 0.53–0.77; mpw/hw: 1.00–1.24; bpw/ apw: 0.87–1.12; pl/mpw: 1.10–1.24; mew/mpw: 1.58–1.89; el/pl: 2.40–2.97; el/mew: 1.66–2.14; mew/bew: 1.23–1.38; bew/mpw: 1.24–1.41; pft/msrw: 1.02–1.31; ptbl/pl: 1.04–1.23; ptbl/ptbmw: ♂ 4.77–6.42 (M: 5.61), ♀ 5.17–8.00 (M: 7.12).
Rostrum subparallel-sided, shortly conically dilated at extreme base ( Figs. 14, 15 View FIGURES 1–15 ), then often slightly narrowed in middle of metarostrum and prorostrum, and weakly obtusely widened at antennal insertion, variable in length and proportions, overlapping in both sexes (see indices above); in profile weakly curved ( Figs. 12, 13 View FIGURES 1–15 ); dorsally and laterally with small irregular setiferous punctures ( Figs. 12 View FIGURES 1–15 , 17 View FIGURES 16–27 ); ventrally punctures confused on prorostrum and arranged in an irregular median row on septum of scrobes ( Fig. 18 View FIGURES 16–27 ); setae on most length of rostrum short and obliquely protruding anterad, only at rostral base dorsally long and erect; surface in basal half of rostrum finely microreticulate both dorsally and ventrally, including bottoms of shallow scrobes; antennal pits distinctly elongate ( Fig. 18 View FIGURES 16–27 ).
Antennae 0.9–1.1 × as long as elytra; antennal insertion ♂: 0.46–0.55, ♀: 0.43–0.51 from rostrum base; length/ width ratio: scape 3.1–4.6, fun1 1.9–3.2, fun2 2.9–3.5, fun6 1.8–2.7, fun7 1.5–2.0, club 5.0–6.5; length of scape/ fun1 1.4–2.1, fun1/fun2 0.75–1.00, fun3 about as long as fun1, fun4 slightly longer than fun3, fun5 slightly shorter than fun4 and fun6, both of similar length, fun7 0.7–0.8 as long as fun6; scape and funicle with protruding setae of various length, some longer than respective antennal joint; club longer than combined length of fun4 to fun7, with shorter but denser protruding setae ( Figs. 20 View FIGURES 16–27 , 28 View FIGURES 28–43 ).
Head short and strongly transverse; epifrons between eyes slightly rising posterad from rostrum base, impunctate, microreticulate, usually with three fine ribs separated by shallow furrows, median rib often obsolescent or missing; vertex flat, irregularly punctate and setose; temple behind eye smooth; eye incompletely surrounded by a single circle of small setiferous punctures ( Figs. 13 View FIGURES 1–15 , 16 View FIGURES 16–27 ), ommatidia small, subocular protruding setae sparse, shorter and lighter from those on epifrons; venter of head between eyes convex and sparsely setose, in middle impunctate ( Fig. 18 View FIGURES 16–27 ).
Pronotum weakly rounded in middle, disc markedly convex, with hardly visible fine line along base and basal edge raised as thin rim; punctuation of disc and sides irregular and variable, coarse and rough in basal half, similar or much sparser in anterior half ( Figs. 9–11 View FIGURES 1–15 ); prosternum 2–3 × shorter than hypomeron; prosternellum rhombic, flattened, obliquely protruding between coxae; hypomeron with few setiferous punctures along procoxal rim ( Fig. 21 View FIGURES 16–27 ).
Scutellar shield flat, black to dark testaceous, concolorous with pronotum.
Elytra elongate, with indistinct separate caudal part, broadest in mid-length (in largest individuals) or slightly behind ( Figs. 1–8 View FIGURES 1–15 ); striae weakly impressed, without sharp edges, catenulate, with sparse, elongate punctures variably distant from each other by 1–3 × their diameters and usually not less than half interval’s breadth; strial punctures with minute light setae, shorter or as long as interspaces between subsequent punctures and hardly visible; strial apical junctions 1+10, 2+9, 3+8 expanded and deepened ( Figs. 8 View FIGURES 1–15 , 16 View FIGURES 16–27 ); intervals slightly convex, shiny or with weak irregular microsculpture, impunctate, in middle about 3–4 × broader than striae; interval 1 weakly raised along suture through middle third of elytral disc; long setae all arising from elytral intervals, in a single regular row on each interval, based in minute sockets separated by a distance subequal to interval’s breadth; basal sutural lock as in Fig. 24 View FIGURES 16–27 ; sutural slot apically with several setae ( Fig. 25 View FIGURES 16–27 ).
Wing as in Fig. 31 View FIGURES 28–43 .
Mesoventrite with paired sub-triangular field of coarse setiferous punctures close to prothorax margin, impunctate and finely microreticulate posteriorly except base of intercoxal process; anapleural sutures visible as fine lines running close to mesocoxae; mesepimeral furrow shallow and lacking edges, expanding upwards, with several setiferous punctures in irregularly multiple rows. Metaventrite punctate and setose on sides, largely impunctate and bare in middle, with a deep posterior median pit; raised posterior rim of mesocoxal cavities separated with a distinct complete line ( Figs. 16, 22 View FIGURES 16–27 ). Abdominal ventrites finely microreticulate, with sparse small punctures bearing light semi-recumbent setae, vanishing only close to middle line of ventrites 1–2 ( Figs. 23 View FIGURES 16–27 , 32 View FIGURES 28–43 ).
Legs: procoxae with sparse, mostly appressed pilosity. Femora slightly differentiated, thinner and longer from fore to hind one, with sparse protruding setae around; profemur regularly inflated, largely smooth and impunctate, microreticulate only close to both articulations. Tibiae microreticulate, with erect setae based in small punctures; inner side of protibia on most length with a narrow strip of fine, appressed, silver to yellowish setae; apical comb of golden setae inconspicuous. Protarsus 3.2–4.0 × as long as wide; length/width ratio of tarsomeres: 1st—2.2–3.2, 2nd—1.2–1.8, 3rd 0.75–0.85; onychium protruding beyond tarsomere 3 by 0.4–0.5 own length; claws as in Fig. 27 View FIGURES 16–27 .
Male. Tibial mucrones all small and pointed ( Figs. 26 View FIGURES 16–27 , 29, 30 View FIGURES 28–43 ). Abdomen variably shaped, 1.18–1.45 × as long as wide; all ventrites with sparse punctuation and fine raised setae; ventrites 3–5 strongly microreticulate; ventrite 5 gently convex, broadly rounded to subtruncate apically, 1.75–2.20 × as long as wide ( Fig.32 View FIGURES 28–43 ). Tergite VII sclerotized as in Fig. 43 View FIGURES 28–43 , with long fringe of microchaetae on posterior margin. Pygidium concealed except for a narrow outer margin; internal tongue-like process markedly transverse ( Figs. 33–35 View FIGURES 28–43 ). Sternite VIII shaped as in Fig. 36 View FIGURES 28–43 , without carinae. Paired sclerites in the membrane between sternites VIII and IX shortly elongate ( Fig. 37 View FIGURES 28–43 ). Spiculum gastrale as in Fig. 36 View FIGURES 28–43 ; arms slightly rounded and expanded on tips; apodeme bent subapically, its apex not expanded. Tegmen as in Figs. 40, 41 View FIGURES 28–43 ; basal piece with long, straight arms; apodeme shorter than basal piece fork, not dilated apically; tegminal plate 1.6–2.0 × as long as wide, widest at articulation to basal piece; parameral lobes separated by short V-like open notch, symmetrically crescentic, lacking pores at their bases; macrochaetae 6–10, varying in length, a few median the longest, subequal to, or longer than entire dorsal layer of tegminal plate; the area between apical sclerotizations and postfenestral plate entirely membranous and transparent except for anterior extensions of lateral prostegial sclerotizations, in middle with triangular field covered with microchaetae; postfenestral plate bar-like, in middle not longer than sclerites on parameral lobes; prostegium with long, acute, sclerotized lateral tails and transparent membranous middle stripe. Penis with pedon and apodemes subequally long; tectum of at most 0.6 pedon length, at basal margin reinforced with darker sclerotization; pedon 3.3–3.7 × as long as wide, parallel-sided in basal 0.6–0.7 of length, variably narrowed distally ( Figs. 38, 42 View FIGURES 28–43 ), with apex flattened and rectangular in shape, in profile weakly sinuous ( Fig. 39 View FIGURES 28–43 ), bearing densely radiate canaliculate lines; endophallus large and complex in its membranous part, in repose multifolded and reaching almost the tips of apodemes; inflated endophallus with four lateral lobes, receiving relatively thick ejaculatory duct dorsally in a microspinose sector at the base of exposed lobate part ( Figs. 44, 45 View FIGURES 44–56 ); endophallic sclerotized armature consisting of a pair of frena accompanied in between with a peculiar sclerite of inverted V-like shape, all laying close to subapical penile orifice in repose ( Figs. 38, 42 View FIGURES 28–43 ); frena long and narrow, subrectangular, having very small, blunt tooth near middle of one long margin ( Fig. 38 View FIGURES 28–43 ), weakly dilated at one end ( Fig. 54 View FIGURES 44–56 ).
Female. Abdominal ventrites less variable, 1.27–1.33 × as long as wide; ventrites 1–2 more convex, and shiny, in middle; ventrite 5 weakly convex and more regularly rounded apically, 2.1–2.4 × as long as wide. Tergite VII with fine carina along broadly rounded apical margin ( Figs. 48, 53 View FIGURES 44–56 ). Tergite VIII subrectangular ( Figs. 46, 49 View FIGURES 44–56 ). Spiculum ventrale (sternite VIII) with broad, anchor-like sternal plate and straight apodeme. Gonocoxites subtruncate apically; styli small, about 1.5 × as long as wide, shortly setose ( Fig. 49 View FIGURES 44–56 ). Bursa large, simply membranous. Spermatheca thin, irregularly c-shaped, with weakly curved cornu, without distinct prominences on a narrow corpus ( Fig. 55 View FIGURES 44–56 ).
Remarks. The pair collected by R. E. Turner in Katberg and preserved while in coitus put some light on the mechanics of copulation after a common dissection. As it can be concluded from Figs. 50–54 View FIGURES 44–56 , the lobate endophallus is entirely introduced into the female bursa, but its function is mainly to fill it in tension for proper positioning of the gonopore close to the opening of spermathecal duct, which is situated at the bottom of the bursa near the branch of the common oviduct. The microspinose field surrounding the male gonopore may eventually help in stabilisation of this accurate position; it is well seen inside the female bursa in Figs. 52, 53 View FIGURES 44–56 . It cannot be deduced from the preparation if the male sclerites enter the female abdomen during copulation. They are seen within the tip of male abdomen ( Fig. 54 View FIGURES 44–56 ), but this may be due to a partial retraction of the evaginated endophallus when the beetles were killed. Judging from the position of the frena in the fully evaginated endophallus, observed in a male of Australian Myrmacicelus luckily preserved in this stage ( Wanat 2001), and their hook-like structure, they are stabilizing the male’s penetration by hooking against the rigid margins of the female abdominal opening. On the other hand, it seems that in Rh. variiforme the position of the endophallus seen in Figs. 50, 51 View FIGURES 44–56 is not far from that natural for copulation, and its sclerites actually do not enter the female’s abdominal foramen, thus relying on a stabilization of mating in the opening of the male abdomen. This could be additionally indicated by the shape of the frena, modified to a form apparently less suitable for hooking. In any case, the peculiar V-like sclerite associated with the frena most likely serves as a kind of spring, stretching the frena when they are in a constricted space, in either the male or female genital tract.
The variation of Rh. variiforme exceeds what is usually observed in the Apioninae . It is seen in the set of measurement indices above, that most of them largely overlap between sexes and nearly all metric sexual differences are vague. The difference in body length between individuals collected from the same plant may well exceed 100%. This is furthermore accompanied with the presence of various colour forms described above. There were found in studied material almost all possible transition stages from entire black to light testaceous body, with only the head and appendices darker testaceous. Moreover, a few specimens known from the northernmost areas (Limpopo, highlands of Mpumalanga) constantly have dark elytra with bluish metallic tinge, eventually combined with red flecks around humeral calli ( Fig. 4 View FIGURES 1–15 ). This might suggest eventual geographic variation, but there are still too few specimens available for study to confirm eventual subspecific status of this northern population. High variation concerns also the shape of the rostrum in both sexes, the punctuation of the pronotum, as well as the coloration and proportions of the antennae. As a rule, the specimens of medium and small body size (<2.5 mm) have relatively longer antennae than larger specimens with body length over 3.0 mm. Likewise, larger specimens have more elongate elytra and abdominal ventrites. In the 2.95 mm long holotype the el/mew index is 2.06, while the length/width of abdomen is 1.45. In dwarf males with body length well below 2.00 mm el/mew index is between 1.65–1.70 and their abdomens are at most 1.25–1.30 as long as wide. Highly variable is also the shape of the male ventrite 5, and in this case is not evidently correlated with body size. Among dissected males the least transverse ventrite 5 is possessed by the holotype (width/length 1.75), while in other specimens, both larger and smaller, the respective ratio is between 1.90–2.20.
Having a solid picture of great infraspecific variation in the studied material, counting approximately 50 specimens coming from a wide range in South Africa, I was unable to find any unambiguous morphological correlation serving as a ground for eventual taxonomic division of this polymorphic species. Moreover, it was observed in Karkloof an aggressive attempt of a male with red elytra to mate with a darker female half of its size, after both had been put together into a vial.
One locality of Rh. variiforme sp. n. in the Western Cape Province was identified from the iSpot website, where the user called sallyslak shared four photos of this characteristic hairy species taken in the garden near Friemersheim (-33.96646 / 22.09085) (https://www.ispotnature.org/communities/southern-africa/view/observation/688433/littlehairy-schnozzbeetle) GoogleMaps .
Biology. Collected from several arboreal genera and species of Celastraceae , like Gymnosporia buxifolia (L.) Szyszyl., G. heterophylla (Eckl. & Zeyh.) Loes. , G. nemorosa (Eckl. & Zeyh.) Szyszyl. , G. rubra (Harv.) Loes. , Pterocelastrus rostratus (Thunb.)Walp. , Cassine crocea (Thunb.) C. Presl. Most often found on various Gymnosporia species , never abundant. Prevailingly in humid forests, occasionally in bushland along rivers. Details of oviposition and larval development are unknown.
Distribution. Eastern and Southern R.S.A. (Limpopo, Mpumalanga, KwaZulu-Natal, Eastern Cape, Western Cape) ( Fig. 289 View FIGURES 289–296 ).
Etymology. The name is derived from Latin adjective varius (stem vari -), linking vowel – i – and adjectival ending formis (from forma, forme in neuter), to reflect great morphological polymorphism of the new species, exceptional in the whole subfamily scale.
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