Amasa circumcisula ( Schedl, 1954 )

Sittichaya, Wisut & Smith, Sarah M., 2022, New species and new records of Amasa Lea, 1894 ambrosia beetles from Thailand (Coleoptera: Curculionidae: Scolytinae: Xyleborini), Zootaxa 5196 (2), pp. 197-210 : 205

Amasa circumcisula ( Schedl, 1954)

( Fig. 5 )

Xyleborus circumcisulus Schedl, 1954: 140 , 151.

Amasa circumcisulus (Schedl) [sic]. Wood & Bright 1992: 682.

Diagnosis: 1.93–2.06 mm long (mean 2.00 mm, n = 3); 2.96–3.17× as long as wide (mean 3.07, n = 3). This species is distinguished by body cylindrical and elongate, pronotum broadly rounded and elongate, type 8, when viewed dorsally, anterior margin serrate; pronotal disc shagreened; antennal club flat without sutures, type 5, elytra strial punctures large, declivital face flat except on medial part of apical margin, declivity glabrous and shining; punctures on striae 1 and 2 distinctly larger than on striae 3; interstriae flat and glabrous; interstriae 1 near on medial apical margin with elevated uniseriate small granules.

Similar species: Amasa similis (Eggers) .

New records: Thailand: Narathiwat Province, Hala-Bala Wildlife Sanctuary , 5°47′44″N, 101°50′07″E, lowland tropical rainforest, 01.i.2015 (1), 01.iii.15 (2), (W. Sittichaya), (1 WSTC) .

Distribution: Indonesia (Java). New to Thailand.

Host plants: Eugenia lineata (Myrtaceae) ( Schedl 1954).

Remarks. Schedl (1954) described this species from Java without designating a holotype. Later (1979) he designated a lectotype and four paralectotypes all from a similar origin, labelled “Batoerraden, G[gunung]. Slamet, Java ”. WS compared Thai specimens from the far south with the lectotype (NHMW) and concluded that the Thai specimens are similar in length with Schedl’s description (1.9 mm) ( Schedl 1954) and lectotype but differ in other body proportions. The lectotype has more similar body proportions to the Thai specimens, but slightly differs from Schedl’s original description. These differences among the original description, lectotype, and three Thai specimens are summarized in Table 1 . It is possible that Schedl’s original description may have been an average of more than one specimen since no type was indicated at that time, and this may explain the slight differences in length and proportions of the lectotype compared to the description.

Figures

FIGURE 5. Amasa circumcisula (Schedl, 1954) A) dorsal view; B) lateral view.