Coccus tumuliferus Morrison, 1921

Gullan, Penny J., Kondo, Takumasa, Fiala, Brigitte & Quek, Swee-Peck, 2018, Taxonomy of coccids (Hemiptera: Coccidae: Coccus L.) associated with Crematogaster ants (Hymenoptera: Formicidae) in the stems of Macaranga plants (Euphorbiaceae) in Southeast Asia, Zootaxa 4521 (1), pp. 1-51 : 43-46

Coccus tumuliferus Morrison

urn:lsid:zoobank.org:act:537C7FF2-8E3B-423A-ADE9-96E5AD7DD249

( Figs 11D , 14 )

Coccus tumuliferus Morrison, 1921: 655 .

Coccus tumulifer Lindinger, 1932f: 197 . Unjustified emendation; discovered by Williams & Ben-Dov, 2009: 46.

Type material examined. Holotype: adult female, SINGAPORE: on Macaranga hypotema [sic, see below], E.E. Green letter dated 8.vi.1916, coll. I.H. Burkill, 1(2, holotype clearly marked and 1 paratype adult female) ( USNM) . Paratypes: same data as holotype but two slides specify "in hollow stems of M. hypotema ", 4(4 adult females, including 1 on slide with holotype, + 2 slides with a number of first-instar nymphs) ( USNM; the 1 slide with 3 paratype females not seen). Morrison's original description refers to five adult females and several mounted "larvae", and this accords with the slides listed above, all of which have Morrison type labels on both the slides and their envelopes. However there is another USNM slide of this species which appears to have been prepared and labelled by Green from original Burkill material as its label starts: "Ctenochiton / tumuliferum / Green, ms. / Part of type / material.)" (details listed immediately below), but these specimens are not mentioned by Morrison in the original description of this species .

Examined non-type material from original collection. SINGAPORE: in hollow stems of Macaranga hypotema [sic], coll. I.H. Burkill, 1(2 adult females + 1 third-instar female) ( USNM; slide labelled by Green and discussed above); in hollow stems of Macaranga hypoleuca , attended by ants, coll. I.H. Burkill, 2(2) ( BMNH). The BMNH also has another 10 slides, with a total of 29 adult females and nymphs, of this Singapore collection from Burkill; PJG examined these slides in 1994 and made notes but did not take measurements. All of these BMNH slides have similar data to the type collection listed above, but they are not type specimens, as explained in the Materials and methods.

Note. The USNM type slides give the host plant as M. hypotema and Morrison (1921) listed the host as M. hypolema , but there is no such species. The BMNH slides give the host as M. hypoleuca , which is a member of the Pachystemon section of Macaranga ( Davies et al. 2001) .

Other material examined. BORNEO: Sarawak, Santubong, ex M. hypoleuca, Dec. 1994 , coll. H.-P. Heckroth, 445, 447, 450, 451 & 453, 5(14 + 1 adult female of C. macarangae ) (2 slides ANIC, 3 slides FRIM). PENINSULAR MALAYSIA: Fraser’s Hill, ex M. hypoleuca, Mar. 1993 , coll. H.-P. Heckroth, #284, 3(3); Gombak, lower logging road, ex M. hosei, Feb. 1992 , coll. H.-P. Heckroth, #230, 2(2; 1 female taken from the mandibles of an ant); Johor, Kota Tinggi to falls, lowland, ex M. hypoleuca , 5 Sept. 1999, coll. S.-P. Quek, SPQ.018, DNA voucher 1(1); Johor, Mawai camp, Ginger Hill, ~ 1.871 N, ~ 103.954 E, <100 m, ex M. hypoleuca , 7 Sept. 1999, coll. S.-P. Quek, SPQ.027, SQP.030 & SPQ.032, DNA vouchers 3(2 adult females + 1 immature female); Johor, Sedili, 14 km from Route 3, <100 m, ex M. hypoleuca , 5 Dec. 1999, coll. S.-P. Quek, SPQ.182, DNA voucher 1(1); Pahang, near Kuantan on road to Pancing Falls, <100 m, ex M. hypoleuca , 15 Sept. 1999, coll. S.-P. Quek, SPQ.054, DNA voucher 1(1); Pahang, Kuantan to Johor Road, 299 km to Johor, lowland, ex M. pruinosa , 16 Sept. 1999, coll. S.-P. Quek, SPQ.062, SPQ.063a & SPQ.064, DNA vouchers 3(3); Pahang, Kuantan to Johor Road, 299 km to Johor, <100 m, ex M. hypoleuca , 16 Sept. 1999, coll. S.-P. Quek, SPQ.066 & SPQ.067, DNA vouchers 2(2); Terengganu, Bauk Hill, <100 m, ex M. hypoleuca , 12 Sept 1999, S.-P. Quek, SPQ.038, DNA voucher 1(1). SINGAPORE: Old Upper Thompson Road, ~ 1.381 N, ~ 103.813 E, <100 m, ex M. hypoleuca , 4 Oct. 1999, coll. S.-P. Quek, SPQ.090, DNA voucher 1(1).

Adult female. Unmounted material. “.. rarely broad oval, but usually broadened behind and triangular with angles rounded; plane of dorsal surface flat, but in dried specimens covered with relatively large knobs having a fairly definite arrangement of a median longitudinal single row and on each side of this two other rows, the outer one forming a continuous row around the body at the margin; dorsally covered with a thin, brittle, whitish but more or less translucent, glassy secretion, very easily broken and usually more or less wanting, molded into elevations and depressions corresponding to those of the body, this covering normally wanting over the flattened extreme margin of the body; body color dull brown, of secretionary covering, as stated, translucent whitish; .. ( Morrison 1921: 655). For the present revision, the available adult females preserved in ethanol were pinkish red in colour ( Fig. 11D ). Although Morrison recorded the body of dry adult females as dull brown, but this is unlikely to reflect the colour in life.

Slide-mounted adult female (n=16, including holotype and paratypes; specimens from Santubong in Sarawak excluded; Fig. 14 ). Body oval to broadly oval, 1.5–2.8 mm long, 1.2–2.4 mm wide, widest in posterior half.

Dorsum. Derm (dd) completely membranous, areolated; with a series of humps (oval to circular raised areas of cuticle) present in a submarginal row of 17 (typically 8 on each side plus 1 medially on head), 3 on each side submedially, and usually 3 medially but these often poorly defined. Dorsal setae (dset) very short, each 2–3 µm long with rounded apex, scattered on dorsum. Simple pores (sp) each 2.5–3.0 µm wide, scattered evenly on dorsum. Preopercular pores (pop) each 3.8–5.0 µm wide, scarce, present in a small group of 1–5 anterior to anal plates. Dorsal microducts (dmic) in areolations each 2.0– 2.5 µm wide, appearing bilocular under high magnification. Anal plates (anplt) each triangular with anterolateral margin longer than posterolateral margin, inner lobes fairly developed, with a tessellated texture, each plate 150–198 µm long, 100–125 µm wide, anterolateral margin 140–163 µm long, posterolateral margin 90–128 µm long; each plate with 14–22 dorsal setae, slender spinose, each 8–23 µm long. Anal ring (ar) probably always bearing 10 setae [ Morrison (1921: 657) says 8 setae, but the thinner setae are difficult to see], each 100–155 µm long.

Margin. Eyespots present slightly removed from dorsal margin, each 20–28 µm in maximum dimension. Marginal setae (mset) of 2 broad types usually not found together on a specimen (but female SPQ.030 with both types): (1) long (20–110 µm) and flagellate, present in 1 or 2 rows (rarely up to 3 rows on part of margin) (as illustrated in Fig. 14 ); (2) short (12–28 µm long) and with apices mostly fimbriate (or at least divided), usually present in a single row, rarely in 2 rows on parts of margin; with about 7–30 marginal setae between anterior and posterior stigmatic areas on each side of body. Stigmatic setae (stgset) of variable length and development, numbering 1–3 but usually 1 (rarely absent) per cleft, median seta 3–25 µm long, lateral ones if present each 3.0– 7.5 µm long, spinose and tapering to a rounded point, rarely 3 very short setae (≤ 5 µm) present.

Venter. Derm membranous. Ventral setae (vset) slender, longest submedially on posterior abdominal segments, each 20–88 µm long, elsewhere shorter, 7.5–40 µm long. Interantennal setae in 2 pairs, each seta 50–70 µm long. Ventral tubular ducts (vtd) present in a broad submarginal band; each duct with outer ductule about 15 µm long, inner ductule about 17.5 µm long, and duct opening about 2.5 µm wide. Ventral microducts (vmic) each about 2 µm wide, scattered fairly evenly on venter. Pregenital disc-pores (pgp) each with 7–9 loculi, each pore 5–7 µm wide. Antennae (ant) usually 7, rarely 6, segmented [ Morrison (1921) recorded 8 segments but this appears to be erroneous], each antenna 210–270 µm long; apical antennal segment 30–43 mm long, with apical prolongation 2–8 µm long on at least 1 antenna (often absent on 1 or both antennae of pair); fleshy setae present on last 3 segments when 7 segmented, and on last 2 segments when 6 segmented. Mouthparts normal; clypeolabral shield 210–270 µm long, 170–235 µm wide; labium 80–100 µm long, 120–150 µm wide. Legs with hind trochanter + femur 155– 195 µm long; hind tibia + tarsus 155–200 µm long; all tarsal digitules each 28–40 µm long; claw digitules each 25– 30 µm long, claws each about 30 µm long. Spiracles normal: anterior peritremes each 45–58 µm wide; posterior peritremes each 50–65 µm wide. Spiracular pores (spp) each 4–5 µm wide, mostly with 5 loculi, rarely 4.

Comments. Adult females of C. tumuliferus can be distinguished from all other species of Coccus known from Macaranga by having the combination of (i) very short dorsal setae that can appear to be absent; (ii) almost always 8 dorsal submarginal raised areas on each side of body plus 1 medially on head (most obvious on live or ethanolpreserved specimens); and (iii) usually 14–22 dorsal setae per anal plate, each slender spinose and mostly ≤ 20 µm long. Adult females of C. tumuliferus are most similar to the adult females of C. caviramicolus , C. pseudotumuliferus and C. secretus , which all also have extremely short dorsal setae, but they differ from females of C. caviramicolus in having marginal setae either flagellate or with few fimbriations (strongly fimbriate in C. caviramicolus ) and anal plates with a ratio for the length of the anterolateral margin to posterolateral margin of 1.12 to 1.38 (ratio mostly 1.41 to 2.06 in C. caviramicolus ); from C. secretus in having dorsal setae rounded at the apices (tapering to a point in C. secretus ) and the dorsal setae of the anal plates are usually much shorter (each 8–23 µm long in C. tumuliferus compared with 15–45 µm long in C. secretus ); and from C. pseudotumuliferus in the number of submarginal raised areas (typically 8 on each side plus 1 medially on head in C. tumuliferus compared with usually 11 on each side plus 1 medially on head in C. pseudotumuliferus ), the shape of these raised areas (usually circular in C. tumuliferus but oval to elongate in C. pseudotumuliferus ), and the number of stigmatic setae (0–3 but usually 1 per cleft in C. tumuliferus compared with usually 3 per cleft in C. pseudotumuliferus ).

Heckroth et al. (1998) recognised C. tumuliferus from both Borneo and Peninsular Malaysia and recorded it as most common on M. hypoleuca , which is a common and widespread tree in both regions (Davies 2001). We had available for study 16 slide preparations, each containing from one to six adult females, made by Heckroth and identified by him as C. tumuliferus from Borneo. Five slides (#445, 447, 450, 451 and 453, ex M. hypoleuca, Santubong [probably on the lower slopes of Mt Santubong], Sarawak) have adult females of C. tumuliferus , but the other 11 slides (#495, 525, 526, 527, 581, 589, 598, 629, 631, 635 and 614, ex either M. bancana , M. hypoleuca , M. indistincta , M. beccariana or M. pearsonii , from three areas in Sabah) contain specimens of C. pseudotumuliferus . Other than the specimens from Santubong, all other records for C. tumuliferus are from Singapore and Peninsular Malaysia and, given that it is unlikely that Heckroth's specimens of C. tumuliferus are mislabelled, the explanation for this distribution is probably geographic. Santubong is in the region of Sarawak closest to Singapore and West Malaysia and may have been isolated from the rest of Sarawak by past geological and environmental conditions. The Kuching area (including Mt Santubong) of western Sarawak is south of the Lupar Valley and a geological fault called the Lupar Line. This fault marks the southwestern boundary of the rock formation called the Rajang Group in Sarawak ( Moss 1998; Wang et al. 2016). The Lupar Valley contains a large river, the Batang Lupar, surrounded by extensive swamp forests, which may have created a barrier to the dispersal of some taxa. A barrier effect of the Lupar Valley has been hypothesised for a species of Malaysian frog for which populations from Peninsular Malaysia and western Sarawak were more genetically similar than populations in western Sarawak were to those in northeastern Sarawak ( Zainudin et al. 2010).

The adult females of C. tumuliferus from Santubong have 7–9 dorsal submarginal humps on each side of the body and of the typical shape for C. tumuliferus ; 12–16 dorsal anal plate setae on the six females for which they are visible clearly; flagellate marginal setae up to 90 µm long (but usually <60 µm) in 1 or 2 rows; 1–4 stigmatic setae per cleft with each seta usually 10–25 (rarely up to 36) µm long; and an apical antennal prolongation 5–8 µm long (rarely 10 µm long on one antenna of a pair); thus these females barely differ in key morphological features from females collected from Singapore and Peninsular Malaysia. Further collecting and molecular assessment of C. tumuliferus from the Kuching region (i.e., south of the Lupar Line) would be valuable. Furthermore, C. tumuliferus may occur in the northwestern part of West Kalimantan but no collections have been made in that region.

Figures

FIGURE 11. Photographs of the dorsum of adult females preserved in ethanol: A–C, C. pseudotumuliferus Gullan & Kondo sp. n., showing variation in the numbers and shapes of dorsal elevations or humps; D, C. tumuliferus Morrison.

FIGURE 14. Adult female of Coccus tumuliferus Morrison. Abbreviations as in Fig. 3.