Cryphalus gnetivorus Johnson, 2020

Johnson, Andrew J., Li, You, Mandelshtam, Michail Yu., Park, Sangwook, Lin, Ching-Shan, Gao, Lei & Hulcr, Jiri, 2020, East Asian Cryphalus Erichson (Curculionidae, Scolytinae): new species, new synonymy and redescriptions of species, ZooKeys 995, pp. 15-66 : 15

Cryphalus gnetivorus Johnson sp. nov. Figures 2D , 3D , 8A-I

Type material examined.

China • 1 ♀ Holotype; Guangdong, Shenzhen, Dapeng dam; 22.6316°N, 114.4624°E; 12 Apr. 2018; You Li leg.; ex. Gnetum luofuense ; reared from dead vines; IOZ(E)225671; UFFE:31751 (IOZ) • 1 ♂ Paratype; same collection data; dissected; UFFE:31753; (UFFE) • 1 ♂ Paratype; same collection data; dissected; DNA: 28S:MT937245, COI:MT937225; UFFE:31752 (UFFE) • 1 ♂ Paratype; same collection data; UFFE:31750 (UFFE) • 8 ♀♀, 7 ♂♂ Paratypes; same collection data except 01 Jun. 2018; UFFE:34924 (NHMUK, 1♀, 1♂; FSCA, 1♀; MZB, 1♀, 1♂; NIAES, 1♀, 1♂; NMNS, 1♀, 1♂; IOZ, 1♂ IOZ(E)225672; RIFID, 1♀; USNM, 1♀, 1♂; ZIN, 1♀, 1♂).

Other material examined.

China • 1; Guangdong, Shenzhen, Yantian; 22.5889°N, 114.2842°E; 08 Apr. 2017; Wei Lin leg.; UFFE:33241.

Type locality.

China, Guangdong, Shenzhen, Dapeng dam (22.6316°N, 114.4624°E).

Diagnosis.

Cryphalus gnetivorus can be distinguished from most of the East Asian Cryphalus by the combination of the size (1.20-1.50 mm), the proportions (twice as long as wide), by the male frons with minute transverse aciculations in upper median area, by the short elytral disc and long, gradual declivity, by the interstrial bristles of approximately even length, widened and rounded at tips, pointing posteriorly, by the female interstrial ground vestiture which is hair like near base and tridentate scale-like on declivity, and by the proventriculus with a wide area of sutural teeth, occupying half of the segment width.

Female. Length 1.25-1.50 mm (holotype 1.45 mm). Proportions 2.0 × as long as wide. Frons with weak aciculations and punctures, and a weak median keel on lower half. Antennal funiculus with four or five segments, the last being short and wide. Antennal club with three straight or weakly procurved sutures. Pronotal colour dark brown. Pronotal profile broadly rounded, widest in line with summit. Pronotal margin armed with 6-8 wide, rather blunt serrations, larger at median. Pronotal declivity with 60-75 wide and blunt asperities (holotype has 71). Pronotal disc approx. three tenths of the pronotal length, asperate texture, most pronounced at median. Pronotal vestiture with golden hair-like setae, with some longer, coarse setae along baso-lateral margin. Suture between pronotum and elytra weakly sinuate. Scutellum small, triangular. Elytra very broadly rounded, disc occupying less than one third of elytral length, and a gradually sloping declivity. Elytra colour dark brown on disc, becoming chestnut-brown on declivity. Striae impressed on disc, gradually becoming less apparent and less impressed on declivity, visible only as row of shallow punctures on lower area of declivity. Interstrial bristles short, flattened near apex with a rounded tip, of a similar length on disc and declivity, curved pointing posteriorly, arranged somewhat irregularly on disc and in a row on declivity. Interstrial ground vestiture completely hair-like at base, barely indistinguishable from strial setae, becoming entirely tridentate scale-like on declivity. Protibiae and protarsi with only straight, hair-like setae. Mesocoxae moderately separated, a little more than distance between metacoxae. Ventrites with mostly single hair like, and some bifurcated setae. Proventriculus not examined.

Male. Similar to female except: Length 1.20-1.45 mm. Frons with minute transverse aciculations in the median upper portion of the frons. Interstrial ground vestiture tridentate scale-like on disc and declivity, more elongate and intermixed with a few hair-like setae near base. Protibiae and protarsi with a few coarse curved setae. Last abdominal ventrite not emarginated. Proventriculus sutural teeth numerous, occupying about half of width of segment, sometimes in indistinct transverse rows of three or more, with an indistinct transition to the apical teeth. Apical teeth almost extending width of segment. Closing teeth extending beyond masticatory brush, branched and finely tapered at tips. Masticatory brush of a similar length to apical plate. Aedeagus short, without obvious end plate. Penis apodemes less than half of the length of penis body. Tegmen with short paired apodemes.

Etymology.

The name is an adjective derived from a combination of gnet the stem scientific name of the host plant ( Gnetum ), a linking vowel - i - and an adjectival suffix vorus, meaning eater.

Distribution.

China (Guangdong).

Recorded plant hosts.

Gnetaceae : Gnetum luofuense C. Y. Cheng.

Remarks.

Gnetum is an unusual leafy gymnosperm distributed in Asia through to New Guinea, which grows as vines or small shrubs. Cryphalus gnetivorus is unusual among the Cryphalus in the area of study in the shape, with a robust pronotum and smaller elytra which is slightly tapered and mostly a gentle declivity, somewhat similar to Eidophelus darwini Eichhoff, 1878, or various Xyloctonini Eichhoff, 1878.

Using the key of Tsai and Li 1963, this species would key to "subgenus Cryphalus " and fail at couplet 2/7 if Gnetum is considered a conifer, and couplet 15/16 if Gnetum is considered a broadleaf. The colour and proportions are similar to Cryphalus eriobotryae Johnson, 2019, but can easily be distinguished by the antennal sutures ( C. gnetivorus : evenly spaced and procurved; C. eriobotryae : unevenly distributed, the third much more procurved than first two), and using the diagnoses above.

Figures

Figure 2. Proventriculus of A Cryphalus artocarpus, UFFE: 33165 B C. dilutus, UFFE: 34684 C C. dorsalis, UFFE: 25581 D C. gnetivorus, UFFE: 31753 E C. itinerans, UFFE: 33178 F C. kyotoensis, UFFE: 33232 G C. lipingensis, UFFE: 28048 H C. mangiferae, UFFE: 34966 I C. meridionalis, UFFE: 28061 J C. morivorus, UFFE: 27604 K C. paramangiferae, UFFE: 34965.

Figure 3. Aedeagus of A Cryphalus artocarpus, UFFE: 33165 B C. dilutus, UFFE: 34684 C C. dorsalis, UFFE: 25581 D C. gnetivorus, UFFE: 31753 E C. itinerans, UFFE: 33178 F C. kyotoensis, UFFE: 31745 G C. lipingensis, UFFE: 28048 H C. mangiferae, UFFE: 34966 I C. meridionalis, UFFE: 28061 J C. morivorus, UFFE: 27604 K C. paramangiferae, UFFE: 34965.

Figure 8. Cryphalus gnetivorus A, C, E, G, H holotype, female, UFFE: 31751 B, D, F, I paratype, male, UFFE: 31753.