Cycadophila (Cycadophila) torquata Skelley, Xu & Tang

Skelley, Paul, Xu, Guang, Tang, William, Lindström, Anders J., Marler, Thomas, Khuraijam, Jibankumar Singh, Singh, Rita & Rich, Stephen, 2017, Review of Cycadophila Xu, Tang & Skelley (Coleoptera: Erotylidae: Pharaxonothinae) inhabiting Cycas (Cycadaceae) in Asia, with descriptions of a new subgenus and thirteen new species, Zootaxa 4267 (1), pp. 1-63 : 36-38

Cycadophila (Cycadophila) torquata Skelley, Xu & Tang , new species

Figs. 11 A–E

Adult diagnosis. A member of Cycadophila (Cycadophila) nigra species group as discussed above, distinguished by the narrowed legs, protibia lacking stout setae apically, short supraocular stria, presence of a small temple behind eye, pronotum notably reflexed along entire lateral carina, and pronotal anterior margin straight.

Adult description. Length 3.50–4.10 mm, width 1.38–1.40 mm. Body in dorsal view elongate, sides nearly straight and parallel, greatest width at middle of elytra; in lateral view convex dorsally. General body and appendage color dark reddish-brown; dorsal surface distinctly punctate, surface appearing shiny, dorsal punctation with short procumbent hairs, ventrally mostly covered with short procumbent setae.

Head in dorsal view conical, gradually narrowed apically, surface convex, distinctly punctured; width 0.72– 0.81 mm; dorsal interocular distance 0.47–0.56 mm, head width/dorsal interocular distance ratio 1.46–1.55, ventral interocular distance 0.35–0.37 mm, head width/ventral interocular distance ratio 2.07–2.19. Eye globular, surrounded by distinct depression (groove), posteriorly bordered by distinct ridge (temple); bordered dorsally with short supraocular stria at basal 1/3 of eye; projected laterally, with large black facets and short, inconspicuous interfacetal setae. Frons with short, dark, subcuticular suture on each side, approximately 1/4 width of frons in length, extending obliquely to lateral margin above and anterior to antennal insertion. Antennal length about 3/4 pronotal width, and slightly longer than head width, antennomere relative lengths from base to end approximately 18:11:12:10:10:10:10:10:13:13:20; 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. Maxillary palpomeres 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 small lateral pockets; labial palpomere III elongate-oval. Mentum and submentum with moderate punctation and setation, setae short. Gular area smooth, without setae or punctation, except near suture with submentum where a shallow but distinct depression present on each side with setose punctures.

Thorax with pronotum transverse in dorsal view, with marginal beads on all sides except anterior margin; length/width ratio 0.69–0.70; disc convex medially, becoming reflexed and flattened laterally; anterior angles not projecting, rounded; lateral carinae nearly straight, nearly parallel, weakly converging posteriorly; lateral carinae with thin bead, bead bearing row of setose punctures; posterior angles rounded, nearly 90°; posterior margin straight laterally, weakly lobed medially; with narrow, short longitudinal furrow posterolaterally, beginning at pore on posterior margin, extending forward and ending abruptly, length of furrows relative to pronotal length 0.19– 0.20. Prosternum with anterior margin slightly emarginate, finely denticulate with fringe of long, anteriorly directed setae; posterior prosternal process truncate and weakly convex in lateral view, weakly projecting. Hypomeron with coarse punctures laterally, medially without longitudinal striations. Scutellar shield transverse, posterior margin projected, pentagonal. Elytra elongate nearly parallel sided, length/width 3.27–3.80, greatest width near midlength; with marginal bead basally, scutellary striole with 10 punctures; intervals of striae with distinct punctures. All elytral punctures bearing a single short seta; seta length approximately interpuncture distance. Punctation on meso- and metaventrite distinct. Metaventrite long, convex laterally, slightly impressed medially, metathoracic discrimen extending slightly over half metaventrite length. Legs narrow, similar in length; femora compressed laterally; tibiae about same length as femora, narrow and parallel-sided to apex. Protibia not dilated at apex, with fine setal fringe on ventral, lateral margin smooth without stout spinules. Meso- and metatibia narrow, similar to protibia.

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 on either side of the middle; II– IV subequal in length; V slightly longer than IV with lateral margins converging posteriorly to a rounded apex bearing row of short appressed, densely arranged setae.

Male genitalia (tegmen and median lobe of aedeagus) twisted approximately 45o toward the left side of animal and resting on side. 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 spatula-shaped parameres. Parameres short, with long setae apically; length/width ratio 2.00. Aedeagus with median lobe short, slender, highly sclerotized, apex long and acuminate. Ratio of median lobe length to penile strut length 1:3; flagellum very fine, or at least not sclerotized. Female unknown.

Type locality. Yibin , Sichuan, China ( USNM).

Range. China (Sichuan) , Thailand (Kaen Municipality).

Material examined. Holotype (by designation) male with the following labels: 1) [rectangular; white; printed in black ink] “ Suifu, Oct.1924, 1 – 3000 ft.”; 2) [rectangular; white; printed in black ink] “Szechuen, CHINA, DCGraham”; 2) [rectangular; red; printed in black ink] “ HOLOTYPE ♂ Cycadophila torquata P. Skelley, G. Xu & W. Tang 2017 ”. Deposited in the USNM . Paratype male: THAILAND: Kaen Municipality , 9-V-1954, R. E. Elbel (1). Deposited in the FSCA .

Etymology. The species epithet, ‘ torquata ’, is Latin for adorned with a necklace or collar, in reference to the prominent ridges (temples) behind the eyes.

Remarks. The type locality Suifu, Szechwan, is now Yibin, Sichuan . The collector, David Crockett Graham, was a missionary studying Chinese language and culture. While performing his studies in Suifu, he made occasional expeditions in the region to collect specimens for the Smithsonian Institution. His field note books reside in the Smithsonian archives (Anonymous 2015). Unfortunately, they contain no entries surrounding the dates the holotype was collected, thus we have no further information on the specimens habits. The type locality, Yibin , is approximately 100–150 km north of the northernmost populations of wild Cycas , including Cycas panzhuaensis in Panzhihua , Sichuan and C. guizhouensis in Guizhou province . The other locality for this species, Kaen Municipality, is likely Kanchanaburi province, Thailand (see Remarks under Cycadophila convexa ) where surveys on three species of Cycas yielded no specimens matching Cycadophila torquata . It is likely this species has no association with Cycas .

The occipital ridge, lack of abdominal calli, head characters, and twisted male genitalia place C. torquata in the nigra group of Cycadophila . This is a strange beetle, looking quite different from the others by the pronotal shape and presence of a temple behind the eye. The latter character is only known from P. kirschii in the group of cycad inhabiting genera. Cycadophila torquata and C. convexa share a straight anterior pronotal margin which is not seen in any other member of Cycadophila , but differ notably in other pronotal characters. Cycadophila torquata and C. abyssa share the straight, parallel-sided lateral pronotal margins and groove around the eye.

The holotype and paratype are similar in all diagnostic characters. The Chinese holotype differs in having deeper depressions at the submental-gular suture, and the temple behind the eye more prominent. Since neither of these specimens have any indication of a cycad association, we cannot assume one exists. Thus, we cannot assume that any population is isolated due to an association with a particular cycad species. Additional specimens and possibly molecular analysis are needed before we can consider these populations as different species.

Figures

FIGURE 11. Photographs of Cycadophila (Cycadophila) torquata, paratype (unless noted): A) dorsal habitus; B) ventral habitus; C) lateral habitus; D) head and prosternum, ventral; E) head and pronotum, dorsal (holotype); F) male genitalia.