Alcidodes dipterocarpi ( Marshall, 1921 )

Lyal, C. H. C. & Curran, L. M., 2000, Seed-feeding beetles of the weevil tribe Mecysolobini (Insecta: Coleoptera: Curculionidae) developing in seeds of trees in the Dipterocarpaceae, Journal of Natural History 34 (9), pp. 1743-1847 : 1819-1828

Alcidodes dipterocarpi ( Marshall, 1921)

Alcides dipterocarpi Marshall, 1921: 166 , ®gs 2,3; Heller, 1934: 296, 297 (compared to

A. mimus ). Alcidodes shoreae Marshall ; Kalshoven, 1956: 83 (nomen nudum). Alcidodes dipterocarpi Marshall ; Haaf, 1961e: 485; Haaf, 1964b: 171; Pajni and Dhir, 1987:

34 (listed).

Robust insects, with pronounced humeral angles; length 4.75 ±8.69 mm (xÅ5 l 6.5, m 7.06), PW 5 2.3±4.2 mm (xÅ5 l3.27, m 3.53), HW5 2.9±5.6 mm (xÅ5 l4.1, m

4.5) (n 5 l56, m 71) (®gures 34, 66, 85).

Head. Rostrum evenly and fairly strongly curved, less punctate, longer and more slender in female (RL 5 1.5±3.63 mm, xÅ5 2.89 mm; RL/PW 5 0.65±0.91, xÅ5 0.82; RB/RD 5 0.71±1.06, xÅ5 0.84; n 5 71) (®gure 209) than in male (RL 5 1.63±2.69,

xÅ5 2.38 mm; RL/PW5 0.64±0.83, xÅ5 0.73; RB/RD 5 0.82±1.13, xÅ5 0.97; n 5 56) (®gure 210).

Thorax. PL/PW, m, 0.53±0.78 (xÅ5 0.66, n 5 71),, l0.48±0.71 (xÅ5 0.64, n 5 56); prothorax lacking tubercle behind fore coxae. Elytra with interstriae wrinkled or with numerous small granules, especially proximally and on disc, strial punctures shallow, narrower than interstriae, humeri with interstria 9 generally very weakly projecting beyond 8 in dorsal view (®gure 34); EL/HW, m, 0.81±1.17 (xÅ5 1.03, n 5 71),, l0.88±1.25 (xÅ5 1.05, n 5 56). Elytra with darker pigmentation on humeri and as scattered markings on rest of elytra, concentrated along interstriae; elytral scales broader and paler on disc than elsewhere, although pattern variable and not distinct. Fore femur with ventral tooth quadrate, with acuminate proximal lobe at c.45ss to long axis of femur, central lobe higher than proximal lobe and at c.90ss to long axis of femur, distal margin weakly serrate or with single tooth or weak lobe, and meeting femur at c.90ss; tooth quite variable (®gures 141, 172, 173); fore tibia with ventral tooth, mid and hind tibiae lacking ventral tooth. Ventral margin of metasternum convex, not strongly divergent from elytral margin.

Abdomen. Male ventrite 5 usually with small circular median depression, not ¯anked by especially developed scales or setae although elongate scales converging near posterior margin to give impression of pair of tufts (®gure 116). Female ventrite 5 virtually ¯at or weakly convex (®gure 117).

Male terminalia. Tergite 7 as in ®gure 385; three plectral tubercles arranged irregularly near posterior margin on each side of midline. Segment 8 as ®gure 386. Genitalia as in ®gures 387±390. Tegmen with parameres separate (®gure 388). Aedeagus boat-shaped, with apex truncate, depressed with respect to sides, with pair of tufts of very long setae, sides weakly diverging (®gure 390), distance from ostium to apex less than width of ostium (®gure 391); ostiolar sclerites fused to aedeagal body elongate, broad, extending inside endophallus, aedeagus curved in side view (®gure 392), base of aedeagus with pair of large membranous pouches (®gure 390, 392 (p)).

Female terminalia. (®gures 393±395) Tergite 7 with 2±3 pairs of plectral tubercles on either side of mid-line in posterior half of tergite, obscure (®gure 393). Tergite 8 with broadly rounded posterior margin, disc and median anterior margin more weakly sclerotized than other margins (®gure 394). Spiculum ventrale (®gure 395) with broad part quadrate, not as long as apodeme. Female genitalia as in ®gures 396±397; hemisternites short, styli relatively long. Spermathecal duct arising at junction of bursa and oviduct; spermatheca with rounded bulb in gland lobe (®gure 396).

Distinguishing features. The external distinguishing features of the species are the form of the fore femoral tooth, which is virtually quadrate (®gure 141, 172, 173) rather than longer than high, as in other members of the group (eg ®gures 142, 176), and the shape of the depression on the male ventrite 5, which is quadrate and occupies almost the whole length of the ventrite (®gure 116).

Comments. Kalshoven (1956) refers to a weevil, Àlcidodes shoreae Marshall’, found in dipterocarp fruits, particularly`pahalar’ fruits in Java and`tengkawang nuts (the fat-containing seeds of Shorea and Isoptera) in Borneo’. This name has not been published elsewhere and the species apparently never described, no specimens so named being found in BMNH or Leiden (Krikken, pers comm.). However, Kalshoven does not mention A. dipterocarpi , as one would expect him to, and there is a specimen in the BMNH collected by Kalshoven from tengkawang nuts, identi®ed by Marshall as A. dipterocarpi . The logical conclusion is that Marshall initially believed the specimen to be distinct from dipterocarpi , but after writing to Kalshoven to this eOEect changed his mind and never described shoreae .

This species is very widely distributed but despite some variability, particularly in the form of the fore femoral tooth, there is no reason to suppose that more than one species is involved.

Despite the name of the species, the larval hosts are almost always members of the genus Shorea . The only specimens taken from any other genus are members of the type series, which are recorded (on two labels out of four) as from Dipterocarpus turbinatus , and two specimens reared from D. obtusifolius seeds in Thailand. Beeson (1941) cites only two hosts, Dipterocarpus tuberculatus and Pentacme suavis (now Shorea siamensis ), although without providing any indication as to where, geographically, the insects had been found. Knowledge of Alcidodes of this group in the Indian area is too limited to suggest at present what other species might be found on D. tuberculatus , so at present Beeson’s host record is regarded as a possibility. The host record of D. tuberculatus in Mathur and Balwant (1959) and Hutacharern and Tubtim (1995) are probably repetitions of Beeson’s record. We believe that specimens present in the BMNH from Burmese `Pentacme suavis ’ dating from before Beeson’s work form the basis of Beeson’s record from this species, which itself is probably repeated in Mathur and Balwant (1960b) and Hutacharern and Tubtim (1995).

Other records of this species, which have not been checked against voucher specimens, are: Dipterocarpus cornutus Dyer ( Natawiria et al., 1986) (species not recorded from Dipterocarpus in Kalimantan); Hopea ferruginea Parijs (Daljeet- Singh, 1974) (probably A. hopeae , A. sterryorum or A. gonzoi ); Shorea acuminata Dyer ( Daljeet-Singh, 1974) (recorded here from this species); S. assamica Dyer ( Daljeet-Singh, 1974) ; S. curtisii Dyer ex King ( Daljeet-Singh, 1974) (no other record known from this host); S. parvifolia Dyer ( Daljeet-Singh, 1974) (recorded here from this species); S. leprosula Miq. ( Daljeet-Singh, 1974) (recorded here from this species); S. bracteolata Dyer ( Daljeet-Singh, 1974) (no other record known from this host); S. smithiana Sym. ( Natawiria et al., 1986) (recorded here from this species); S. roxburghii G. Don. ( Hutacharern and Tubtim, 1995) (recorded here from this species); S. platyclados V. Sl. Ex Foxw. ( Daljeet-Singh, 1974) (no other record known from this host).

Beeson (1941, 1961) refers to a description of the larva of this species in Gardner (1938). However, there is no description of the species in that paper, and no other has been found.

Specimens examined

LECTOTYPE m, India, here designated, with labels:`LECTO- / TYPE’ and`TYPE’ and` Out of Ingyeui / seed Dehra Dun’ and` Alcides / dipterocarpi / TYPE Mshl.’ and`Pres. By / Imp. Bur. Ent. / Brit. Mus. / 1921 ±273.’ and`304’. ( BMNH).

PARALECTOTYPES: India, (3mm), same data as Lectotype, two with seed identi®ed as Dipterocarpu s turbinatus (BMNH) .

Other specimens. Myanmar [Burma]: 1, l 2mm, Bhamo, Shwegu Res., 24± 25 May 1929, (Mg. Onn) ex fruit Pentacme suavis [5 Shorea siamensis ] (BMNH).

Thailand: Huay Kha Khaeng Wildlife Sanctuary, 23 April± 15 May 1996 (Ghazoul) reared from seeds of: Dipterocarpus obtusifolius (2mm) and Shorea siamensis (2 ll, 4mm) ( BMNH); 3 ll, 3mm, Sakarach; Nakhronrachasima, v.1983 (Eungwijarnpanya), reared from seeds of Shorea siamensis (BMNH, RFDT) ; 1m, same data, but ex S. X oribunda [5 roxbughii] ( BMNH); 1m, Chaing Mai, Doi Chiang Dao W.S., 18 April 1994 (Kitching et al.), reared from seeds of Shorea roxburghii (BMNH) ; 2 ll, 3mm, Soppong Pai; 1800 m; 1± 8 May 1993. (Pacholatko and Dembicky) ( ARC).

Laos: 1, l Sayboury Prov. , Sayboury, 20 October 1966 ( BPBM) .

Singapore: 1, l(Saunders) ( BMNH).

Malaysia: Peninsular Malaysia: 1m, Matang, 6 February 1914, 2000¾ [c. 600 m] ( BMNH); 4mm, Gunong Angsi, Negri Sembilan, 2000±2700¾ [c. 600±810 m], April 1918 ( BMNH); 1m, no locality, 14 September 1916,`on camphur seed’ ( BMNH); 1, l Selangor, Kepong, 25 January 1937, ex fruit Shorea curtisii (BMNH) ; 3mm, Selangor, Kepong, Ulu Gombak, ex seed Shorea macroptera ; 1, l Malaya, Pahang, Bentong, Kepong, FRI, 31 January 1973, ex seed Shorea parvifolia ; Pasoh F. R., Negri Sembilan, 1985±1986 (Toy), reared from seed of: Shorea macroptera (15 ll, 8mm), S. acuminata (2 ll, 4mm), S. parvifolia (2 ll, 2mm), S. leprosula (7 ll, 13mm), S. ovalis (1, l 1m); 1m, Selangor, Kepong Dipterocarp Arboretum, August 1985, (Toy), reared from seed of Shorea argentifolia . ( BMNH).

Malaysia: Borneo: Sarawak: 1m, W. Sarawak: Quop, 2 February 1914 (Bryant) ( BMNH); 4 ll, 6mm, October 1976, (via Kew) ex Shorea almon (BMNH) ; Belaga Dist. , Long Linau, 19 March 1990, (Riedel) ( ARC) .

Malaysia: Borneo: Sabah: 13 ll, 17mm, Ranau , 7 km Marmut, July 1990 (S. Lantoh), ex Shorea smithiana (FRCS) .

Brunei: Temburong Distr., Kuala Belalong, September ± October 1992 (Lyal and Margerison Knight), reared from seeds of: Shorea isoptera (1, l 1m); Shorea ovalis (1m); unidenti®ed dipterocarp (1 l) ( BMNH, RBM).

Indonesia: Borneo: Kalimantan: Gunung Palung Nature Reserve, Cabang Panti Research Station, January± April 1991 (Curran), reared from seeds of: Shorea ? coriacea (1 l); Shorea coriacea (16 ll, 15mm); Shorea crassa (1, l 1m); Shorea johorensis (15 ll, 14mm); Shorea kunstleri (12 ll, 15mm); Shorea leprosula (21 ll, 18mm); Shorea ovalis (21 ll, 24mm); Shorea parvifolia (18 ll, 16mm); Shorea parvistipulata (6 ll, 6mm); S. pauci X ora (2 ll, 1m); S. quadrinervis (7 ll, 5m); Shorea rubra (18 ll, 10mm) ( BMNH, MZB, UMMZ).

`Borneo ’: 1, l March 1931, (Kalshoven), ex`tengkowana’ fruit ( BMNH) .

Philippines: 1m, Mindanao : Butuan (Baker) ( USNM) ; 1m, Mindano: Kolambagan (Baker) ( SMTD) ; 1m, Negros: Cuernos Mts (Baker) ( SMTD) ; 1m, Samar: Borongan (Schultze) ( SMTD) .

Range. India, Myanmar, Thailand, Laos, Peninsular Malaysia, Singapore, Borneo, Philippines. Given the widespread localities from which this species has been collected, additional records from right across south-east Asia can be expected.

Hosts. Dipterocarpus turbinatus Gaertn. f., Dipterocarpus tuberculatus Roxb. (?), Dipterocarpus obtusifolius Teysm. Ex Miq. , Shorea acuminata Dyer , S. almon Foxw. , S. argentifolia Sym. , S. coriacea Burck , S. crassa Ashton , S. curtisii Dyer ex King , S. isoptera Ashton , S. johorensis Foxw. , S. kunstleri King , S. leprosula Miq. , S. macroptera Dyer , S. ovalis (Korth.) Bl. , S. parvifolia Dyer , S. parvistipulata Heim , S. pauci X ora King, S. quadrinervis Sloot. , S. roxburghii G. Don. , S. rubra Ashton , S. siamensis Miq. , S. smithiana Sym.