Crenidorsum aroidephagus Martin & Aguiar

Martin, J. H., Aguiar, A. M. F. & Baufeld, P., 2001, Crenidorsum aroidephagus Martin & Aguiar sp. nov. (Sternorrhyncha: Aleyrodidae), a New World whitefly species now colonising cultivated Araceae in Europe, Macaronesia and The Pacific Region, Zootaxa 4, pp. 1-8 : 3-7

Crenidorsum aroidephagus Martin & Aguiar sp. nov. ( Figs 1-3 )

Crenidorsum sp. L. Nakahara, 1981a: 336; Paulson & Kumashiro, 1985: 110, 119.

PUPARIUM ( Fig. 1 ). Habitus. Scattered under leaves, not in distinct feeding groups. Puparia do not secrete any visible dorsal or periferal wax coating, being cryptic when feeding and silvery when the adults have emerged. Shortly before emergence, the eyes of the adult can be clearly seen through the puparial cuticle, along with the developing body structure ( Paulson & Kumashiro 1985: 119, Fig. 3 F).

Margin. Outline elongate­oval, 0.80­1.10 mm long, 0.50­0.80 mm wide, 1.40­ 1.65 times longer than wide, generally widest at abdominal segment I/II (n=25). Anterior and posterior marginal setae present, fine, similar to each other, up to length of operculum. Margin evenly crenate, typically 14­16 rounded teeth occupying 0.1 mm of margin (n=43); marginal teeth without glandular bases; margin not modified at thoracic and abdominal tracheal openings.

Dorsum. Chaetotaxy comprises setae that vary in length markedly, even within samples (see Table 1 ), ranging from short and stout, with sharply acute apices, to very long and hair­like: single pairs of cephalic (10­300 m), mesothoracic (typically 5­30 m), metathoracic (typically 5­30 m), 8th abdominal (most 50 m) and caudal (5­100 m) setae usually present (n=44), but see comments. A pair of distinct longitudinal folds leads from lateral to cephalic setae to abdominal segment V and, together with a margin­concentric fold anterior to cephalic setae, define the submedian area of the puparium, often as a distinct shallow rhachis; longitudinal folds slightly and variably scalloped, especially thoracically ( Fig. 2 ). Longitudinal moulting suture slightly crimped in appearance ( Fig. 2 ), reaching puparial margin, dividing the cephalic margin­concentric fold into two sections; transverse moulting sutures almost reach longitudinal subdorsal folds. Dorsal disc generally finely corrugate with very closely paired geminate pore / porettes distributed in an even pattern over dorsal disc; in addition to 2­4 geminate pore / porettes on each of abdominal segments II­VII, between the longitudinal folds, clusters of 2­4 simple thickrimmed pores are also present just mesal to the folds, with similar pores, sometimes clustered, also unevenly distributed adjacent to the folds cephalothoracically ( Fig. 2 ). Meso­/ metathoracic and abdominal segmentation distinct submedially, abdominal segment VII only slightly reduced in length medially, pockets distinct. A shallow ­shaped elevation is evident surrounding the vasiform orifice in many individuals (particularly clear in Fig. 1 , and see Fig. 3 ), defining a caudal furrow which terminates at the caudal setal bases, not the puparial margin. Vasiform orifice subcircular, almost fully occupied by the rounded­trapezoidal operculum. Lingula usually folded with its head between posterior edge of operculum and rim of vasiform orifice, appearing crescent­shaped ( Fig. 3 ), with its apical setae directed upwards; when unfolded ( Fig. 1 ) the lingular head is seen to be globose, similar in size to operculum, finely setose and with acute apical setae around 30 m long.

Ven te r. Cuticle diaphanous and smooth; thoracic tracheal folds completely unmarked, except as very slight differential staining in some post­emergence pupal cases; caudal tracheal folds slightly marked by very fine stippling, posterior to vasiform orifice (between posterior abdominal spiracles). Ventral abdominal setae almost underlying eighth abdominal setae, very fine and typically 25­ 30 m. Middle and hind legs each with a tiny basal seta usually just discernible, no longer than its own base. Each leg with an apical disc, usually termed “adhesion pad”; antennal bases placed antero­mesal to fore legs.

MATERIAL EXAMINED. HOLOTYPE puparium, Madeira, Funchal, on Epipremnum aureus , 16 March 1999 (Aguiar) ( BMNH). PARATYPES: 28 puparia, Madeira, same data as holotype ( BMNH, ICLAM, USNM); 42 puparia, São Martinho, on Anthurium hybrid, February & November 1997; November 1998 (Aguiar) ( BMNH, ICLAM); 8 puparia, Madalena do Mar, on Philodendron sp., 26 October 1998 (Aguiar) ( ICLAM); 22 puparia, Germany, Berlin Botanic Gardens, on Philodendron gloriosum , March 2001 (Baufeld) ( BBA, BMNH, USNM); 1 puparium, Belize, Cayo, Chiquibul Forest Reserve, 2­3 km Las Cuevas ­ Monkey Tail Branch, on undetermined aroid vine, 0 5 March 1996 (Martin) ( BMNH); 1 puparium, Cayo, Chiquibul Forest Reserve, Las Cuevas, on Araceae , 0 3 March 1996 (Martin) ( BMNH); 9 puparia, 1 third­instar larva, Brasil, S.P.,?Campinas, on Syngonium sp., received March 1983 (via Lourencão) ( BMNH); 8 puparia, Costa Rica, San Jose, on? Philodendron sp., 22 January 1983 (Martin) ( BMNH); 5 puparia, Hawaii, Honolulu, Foster Botanical Gardens, on Philodendron sp., 10 April 2001 (Kumashiro & Dooley) ( APHIS, BMNH). OTHER MATERIAL: 4 puparia, 1 third­instar larva, Costa Rica, Heredia Prov., 15 km north of Puerto Viejo, on? Philodendron sp., 0 3 February 1983 (Martin) ( BMNH); 1 parasitised puparium, Heredia Prov., 10 km north of Puerto Viejo, on Matisia ochrocalyx (Bombacaceae) , 0 2 February 1983 (Martin) ( BMNH); 12 puparia, 1 third­instar larva, 1 second­instar larva, Panama, Canal Zone, Barro Colorado Island, on? Philodendron sp., 13 March 1983 (Martin) ( BMNH).

DISTRIBUTION. Neotropical Region ­ Belize, Brasil, Costa Rica, Panama; Pacific Region ­ American Samoa, Hawaii; Palaearctic Region ­ Germany (under glass), Madeira; Nearctic Region ­ California, Florida.

RECORDED HOST PLANTS. Araceae : Anthurium crenatum , A. lindenianum , A. longissimum , A. spp.; Culcasia scandens ; Epipremnum aureus , Monstera deliciosa var. borsigiana ; Nephthytis sp.; Philodendron gloriosum , P. spp.; Rhaphidophora korthalsii ; Spathiphyllum sp.; Syngonium podophyllum , S. cf. salvadorense, S. spp.; Xanthosoma sagittifolium . [ Bombacaceae : Matisia ochrocalyx ].

ETYMOLOGY. The specific name reflects the wide range of aroid hosts colonised by this whitefly.

COMMENTS. The puparium of this species displays little phenotypic plasticity, except in the dorsal setae. These vary greatly in length, and precisely which setae become much enlarged (in any individual) appears random, although usually enlargement occurs in pairs (see Table 1 ). In other specimens, some setal pairs are extremely short, again usually in pairs. Within the invasive populations, away from the Neotropics, the mesothoracic setae are always visibly present, but those from some Neotropical samples have the mesothoracic pair almost, or entirely, undetectable. Although it is considered that samples devoid of visible mesothoracic setae are most likely to be conspecific with those which clearly do possess them, the slight doubt leads to the decision to omit from the paratype series those samples without evident mesothoracic setae. A single parasitised specimen, damaged but apparently C. aroidephagus , collected from Matisia ochrocalyx (Bombacaceae) in Costa Rica is present in BMNH. In Madeira, several puparia collected from Philodendron sp. and Epipremnum aureus were parasitised by Cales noacki (Howard) (Eulophidae) and others, collected from an Anthurium hybrid, by Encarsia hispida (De Santis) (Aphelinidae) .

Figures

FIGURE 1. Computer-montage image of slidemounted puparium of Crenidorsum aroidephagus Martin & Aguiar sp. nov. ex- Philodendron gloriosum, Berlin Botanic Garden, with lingula unfolded and excluded from vasiform orifice.

FIGURES 2 ­ 3. Crenidorsum aroidephagus Martin & Aguiar sp. nov. drawn from specimens ex­ Philodendron gloriosum, Berlin Botanic Garden. (2) Submedian detail of meso­ and metathorax, particularly showing setae, scalloped longitudinal folds and distribution of geminate pore / porettes and thick­rimmed pores; (3) region of vasiform orifice, with lingula in resting, included, position.

Tables

TABLE 1. Puparial seta measurements of Crenidorsum aroidephagus Martin & Aguiar sp. nov. from Madeira (µm).

Sp.no	Cephalic	Mesothor.	Metathor.	8th abd.	Caudal	Ventral abd.
1	­	­	­	5­7.5	5	27.5
2	­	13.8	17.5	5	12.5­17.5	30­52.5
3	­	5­11.3	11.3	12.5	5­6.3	25
4	35	12.5	­	7.5	52.5­67.5	25­27.5
5	283.1­295.8	109.7­249.9	272.9­290.7	90­125	112.5	27.5
6	13.8	­	­	7.5	13.8­17.5	27.5
7	­	­	­	­	­	25­26.3
8	­	12.5	­	15­16.3	20­27.5	25­26.3
9	12.5	12.5	17.5	10­17.5	11.3	27.5
10	28.8	­	­	16.3	15	25
11	­	­	­	­	­	30
12	­	­	­	­	78.8	­
13	260.1	21.3	36.3	21.3­27.5	58.8­102.5	25
14	­	­	8.8­17.5	5­7.5	7.5	22.5
15	23.8	­	15	10	20	25
16	­	­	­	­	105­130	25
17	­	10	15­22.5	17.5­21.3	50­58.8	23.8
18	11.3	5	5	6.3	7.5	25
19	20­27.5	12.5­15	25­27.5	22.5	­	25
20	­	12.5	6.3­10	12.5­13.8	10­12.5	26.3
21	8.8	7.5	8.8	10	7.5	28.8
22	15	12.5­15	13.8	10	15	25
23	30	15	37.5	20	­	28.8
24	­	­	­	­	22.5	­
25	17.5	10­15	12.5	6.3­7.5	15	10­22.5
26	28.8­26.3	13.8	17.5	12.5­16.3	22.5	25
27	­	­	­	­	12.5	27.5
28	20	12.5	15	15	­	27.5
29	12.5	6.3	11.3	5	8.8	30
30	55	15	35	­	103.8­117.5	21.3
31	­	­	15	10	3.8	27.5
32	13.8­16.3	7.5	17.5	10	­	­
33	34	­	6.3	­	11.3	­	15	11.3	10	10	5	25	­
34	6.3	11.3	15	10	5	­
35	­	6.3	­	5	10	28. 8
36	­	10	13.8­17.5	11.3	27.5­38.8	­
37	311.1­321.3	20.4	191.3­280.5	25.5	53.6­68.9	­
38	280.5	10	115­225	42.5	­	28.8
39	336­357	50­82.5	293.3­300.9	80­87.5	185	27.5
40	10­21.3	6.3	15	6.3	41.3	­
41	316.2	18.8	270.3­285.6	16.3­35	75­120	25­32.5
42	323.9­351.9	22.5­27.5	152.5­153.8	62.5­63.8	152.5­156.3	­
43	265.2­275.4	25­30	200	52.5	98.8­102.5	­
44	316.2­321.3	23.8­25	60	25­31.3	97.5­105	35