Cycadophila yunnanensis (Grouvelle) Grouvelle, 2015

Xu, Guang, Tang, William, Skelley, Paul, Liu, Nian & Rich, Stephen, 2015, Cycadophila, a new genus (Coleoptera: Erotylidae: Pharaxonothinae) inhabiting Cycas debaoensis (Cycadaceae) in Asia, Zootaxa 3986 (3), pp. 251-278 : 270-275

Cycadophila yunnanensis (Grouvelle) , new combination

( Figures 9–10 )

Pharaxonotha yunnanensis Grouvelle, 1916: 61 ; Schenkling, 1923: 15; Mader, 1926: 721; Schenkling, 1928: 31; Wegrzynowicz, 2007: 536.

Adult diagnosis. Distinguished from other Cycadophila spp. by its smaller body with or without color pattern, distinct supraocular stria that is less than 1/3 length of the eye, weakly depressed submental-gular region, and male with a small rounded swelling near the middle of the medial metatibial margin.

Adult male description. Length 3.12–3.88 mm, width 1.29–1.65 mm. Body in dorsal view elongate, sides nearly straight and parallel sided, greatest width at middle of elytra; in lateral view convex dorsally. General body and appendage color dark reddish-brown, pronotum occasionally with orange-brown sides; elytra of type specimens entirely dark brown ( Fig. 9 ) or with light central stripe (see variation in Figs. 10 A–C); dorsal surface distinctly punctate, surface appearing shiny, glabrous, short procumbent hairs protruding out of punctures, ventrally mostly covered with short procumbent setae ( Figs. 9 C–F).

Head in dorsal view conical, gradually narrowed anteriorly, surface convex, distinctly punctured ( Figs. 9 C, E); width 0.8–0.9 mm; dorsal interocular distance 0.48–0.55 mm, head width/dorsal interocular distance ratio 1.68, ventral interocular distance 0.40–0.45 mm, head width/ventral interocular distance ratio 2.00–2.06. Eye globular; bordered dorsally with short supraocular stria at basal 1/3 of eye; projecting laterally, with large black facets and short, inconspicuous interfacetal setae. Frons with a short, dark, subcuticular suture on each side, approximately 1/ 4 width of frons in length, extending obliquely to lateral margin anterior to antennal insertion. Antennal length about 3/4 pronotal width, slightly more than head width, antennomere relative lengths approximately 16:13:14:10:10:10:10:10:13:13:20; antennomere I (scape) fairly large, slightly elongate, antennomere II slightly smaller than III; IV–VIII small, width equals length; club fairly large, IX–XI similar in length, XI globular. Clypeus truncate anteriorly, anterior margin with long setae; densely punctate; somewhat emarginate, with narrow margin. Mandible with 3 apical teeth; prostheca extending from mola halfway to apical teeth, length,about ½ width, edge nearly straight, with fringe of hairs along dorsal base that extends to the proximal apical tooth; mola with carinulation and small spines. Labrum transverse, about 2 times broader than long; anterior margin fringed with long bristles, especially dense medially. Hypopharynx with thin setae directed medially. Maxilla with cardo expanded apically; stipes narrowly triangular, apically acute, partially overlapping with palpiger; galea and lacinia with long, densely aligned setae; setae on the lacinia thick and strong, but distinguishable hooks absent from surrounding dense setae; galea wider than lacinia. Maxillary palp 4-segmented, palpomere I very small; II, III slightly longer than wide, IV elongate oval, apex densely papillate, relative lengths of II–IV approximately 4:3:7. Labium with mentum pentagonal with carina forming triangular plate projecting medially, with distinct lateral pockets; labial palp 3-segmented; palpomere I small, elongate; II transverse; III large, ovate. Mentum and submentum with moderate punctation and setation, setae short. Gular area smooth, without setae or punctation, except near suture with submentum, where shallow depression present with setose punctures.

Thorax with pronotum transverse in dorsal view; with marginal beads on all sides; length/width ratio 0.64– 0.70, convex, nearly parallel-sided; anterior angles projecting, weakly angulate; lateral margins nearly straight, with thin bead, bead bearing row of setose punctures; posterior angles sharp, nearly 90o; posterior margin projecting medially; with a narrow, short longitudinal furrow posterolaterally, beginning at pore on posterior margin, extending forward and ending abruptly, length of furrows relative to pronotal length 0.14–0.18. Prosternum in ventral view convex; anterior margin slightly emarginate, finely denticulate with row of long, anteriorly directed setae; prosternal process truncate apically. Hypomeron laterally with coarse punctures, medially without longitudinal striations. Scutellar shield transverse, posterior margin clearly projected, pentagonal. Elytra in dorsal view elongate, nearly parallel sided, length/width 3.29–3.45, greatest width near midlength; with marginal line basally, 10 complete striae of moderate puncture size, scutellary striole with 8–10 punctures; intervals of striae with distinct punctures. All punctures of elytral striae bearing a single short seta; seta only visible in profile, extending slightly out of puncture. Punctation on meso- and metaventrites distinct. Metaventrite long, convex laterally, slightly impressed medially, metathoracic discrimen extending slightly over half metaventrite length. Legs narrow, similar in length; procoxa oval; mesocoxa globular; metacoxa transversely elongate-oval; trochanters obliquely truncate apically; femora compressed laterally; tibiae shorter than femora, weakly dilated to narrow apex. Protibia not dilated apically, with fine setal fringe ventrally, lateral margin smooth, lacking stout spinules. Meso- and metatibiae narrow, similar to protibia. Metatibia with slight rounded swelling on apical half of medial margin ( Figs. 10 B–C).

Abdomen with 5 ventrites bearing fine punctures; anterior margin with intercoxal process narrow, with triangular point anteromedially, lateral edges slightly projected, lateral and posterior margins arcuate, converging posteriorly; anterior and posterior margins of ventrites more or less straight; ventrite I lacking subcoxal line, slightly longer medially than II; I–IV apparently lacking erect sensory hairs located adjacent to the midline (at least none were observed on available specimens); II–IV subequal in length; V slightly longer than IV with lateral margins converging posteriorly to a rounded apex, with row of short appressed, densely arranged setae.

Male genitalia (tegmen and median lobe of aedeagus) twisted approximately 45o toward the left and resting on side ( Fig. 9 G). Tegmen sclerotized, triangular, gently twisted; with anterior region ring-like, posterior region sheath-like, posterior margin slightly arcuate; lateral margins gradually converging posteriorly; dorsally with 2 large, elongate, somewhat coniform-shaped parameres. Parameres apically with long setae; length/width ratio 2.0. Aedeagus with median lobe short, slender, highly sclerotized, apex long and acuminate. Ratio of penile strut length to median lobe length 5:1.

Female similar to male except with metatibia without slight rounded swelling on apical half of medial margin ( Fig. 10 A), pygidium truncate, not as well developed. Genitalia with gonocoxites triangular, gradually narrowing posteriorly; apices of gonocoxites laterally with concave impression and setae. Gonostylus small, inserted at the concave impression of the gonocoxite, with several short setae and 1 long seta. Valvifers posteriorly expanded. Spermatheca elongated, C-shaped.

Variation. The original syntypes of C. yunnanensis ( Fig. 9 A) are mostly teneral, with two dark adults. The teneral specimens exhibit a vague central stripe on each elytra ( Fig. 10 B). Series of specimens from independent collecting events show greater variation in the distinctness of this central elytral stripe as well as the presence of lateral stripes ( Fig. 10 C). Elytra of these series vary from entirely dark brown to sharply striped with intermediate color morphs displaying varying degrees in size and distinctness of these stripes, as well as some in which the stripes are reduced to a single humeral and apical spot.

Type locality. Yunnan [Coll. Grouvelle-Paris].

Range. Known from Guangxi and Yunnan provinces, China and Manipur state, India.

Material examined. Six syntypes with the following labels ( Fig. 9 B): 1) [rectangular, red, hand written in black ink] Yunan Mission; 2) [rectangular, pale red, printed in black ink] Type; 3) [rectangular, white, hand written in black ink] Pharaxonota [ Pharaxonotha ] yunnanensis Grouv. (Grouvelle collection - BMNH, examined). The sixth specimen, a male ( Figs. 9 A, C–G) is here designated as the lectotype and placed on a separate card labeled as lectotype. The remaining specimens are here designated as paralectotypes. A red lectotype and yellow paralectotype labels stating “ Pharaxonotha yunnanensis Grouvelle , des. P. Skelley 2014” have also been placed on the pin with these specimens.

Other materials considered C. yunnanensis , that show much color variation as discussed above, include: CHINA: Guangxi: [Debao Co.]: Fuping, ex ♂ cone Cycas debaoensis , N23°29’50” E106°12’87”, V-2001, W. Lu (9); N23°29.643', E106°12.915', 21-V-2004, W. Tang, #1 (542); N23°29.663', E106°12.903', 21-V-2004, W. Tang, #7 (13); 21-V-2004, W. Tang, #31 (31); N23°29.595', E106°12.944', 21-V-2004, W. Tang, #210 (78); N23°29.624', E106°12.980', 21-V-2004, W. Tang, #331 (30); N23°29.643', E106°12.914', 26-V-2006, W. Tang, #1 (31); N23°29.601', E106°12.862', 26-V-2006, W. Tang, #2 (37); N23°29.597', E106°12.863', 26-V-2006, W. Tang, #4 (11); 24-V-2008, W. Tang (75); [Napo Co.]: Dingye, N23°24’26” E106°01’27”, 22-V-2004, W. Tang, #1 (56); #2 (20); India: Manipur: Nongmaiching, ex Cycas pectinata ♀ cone, 2007, J. Singh & R. Singh (2). These are deposited at ANIC, BMNH, FSCA, IZCAS, MNHN, NZAC, USNM.

Remarks. Specimens placed here show color pattern variation from solid color to striped elytra ( Fig. 10 ), with intermediate color morphs. Molecular analysis of the 16S rRNA gene for 25 individuals of the C. yunnanensis morphotype from the Fuping population reveals three variants of this gene ( Fig. 11 ). At least two of these genotypes are found in the Napo population and one as far away as Manipur, India on another species of Cycas (data not shown). This color variation is found within at least two of these genotypes. Although morphological analysis has not yielded any data to support more than one species being present, the genetic variation is relatively high for this species and there may be cryptic species present. Dissection of adults confirms cycad pollen in their guts. Adults are found in small numbers in male cones of Cycas debaoensis at the early stage of elongation and pollen shed and they account for a small percentage of the adult Cycadophila present at this stage (range 3.3– 30.3%, mean = 10.9%, n = 5 cones), but numbers increase up to hundreds in cones that have completed pollen shedding and C. yunnanensis usually makes up the highest proportion of adult Cycadophila at this stage (range 41.1–100.0%, mean = 75.3%, n = 7 cones). No larval morphotype has been found in Cycas debaoensis cones which may correspond with C. yunnanensis , and this species may be also be an opportunistic visitor that reproduces and feeds on alternative hosts.

Figures

FIGURE 9. Photographs of Cycadophila yunnanensis types: A) Six syntypes (red arrow pointing to lectotype, rest are paralectotypes); B) Label of types; C – E) Lectotype male dorsal, ventral, and lateral habitus; F) Head to metaventrite, ventral view of lectotype; G) Lectotype male genitalia.

FIGURE 10. Photographs of Cycadophila yunnanensis variation from CHINA: Guangxi, Dingye. A) Female; B – C) Male (note weakly curved metatibia).

FIGURE 11. Phylogenetic trees based on 16 S rRNA gene sequences of four species of New World Pharaxonotha and four species of Asian Cycadophila found on Cycas debaoensis and using: A) Maximum likelihood analysis; B) Neighbor joining analysis; C) Maximum parsimony analysis. Scale bars indicate base pair substitutions per nucleotide position; numbers on the branches of the trees are bootstrap values. No test was used for long-branch attraction.