Aleuroplatus martini, Valencia & Evans, 2024

Valencia, Luis & Evans, Gregory A., 2024, Review of the genus Tetralicia (Hemiptera: Aleyrodidae) and description of two new species of whiteflies found on avocado trees in Peru, Zootaxa 5403 (2), pp. 197-238 : 227-231

Aleuroplatus martini n. sp.

( Figs. 9–11 )

Diagnosis⸺Among the New World species of Aleuroplatus that are dark brown and black in color, oval to broadly oval in shape and have a strong rachis on the abdomen, the new species is similar to A. sculpturatus Quaintance & Baker, 1917 , A. cockerelli ( Ihering, 1897) and A. gratiosus . It can be distinguished from A. sculpturatus which has a very short, transverse vasiform orifice and operculum and is dark brown with the central region much paler and from A. cockerelli which has the lateral margin slightly differentiated at tracheal opening by a row of 5 shorter teeth, the submargin with a series of 2 rows of pores and the rachis is less pronounced. Aleuroplatus martini is most similar to A. gratiosus but can be distinguished from that species which has the operculum cordate and a row of alternating light and dark, rectangular shaped figures along the margin; whereas A. martini has a rectangular-shaped operculum and the lateral margin in concolorous ( Fig. 10 ).

Puparium⸺In nature the puparia of A. martini are bright black, oval in shape, covered by a couple of wax rods. The wax rods excreted along the body of the puparia are of sulphur yellow in color. The surface of the wax rods shows a liquid on the top ( Figs. 1E , 9D ). The nymphs of the early stages are transparent yellow and only the later immature stages are black with the rods of colored wax.

Slide specimen⸺ Body oval-shaped, about 1.4x as long as wide, lateral margin crenulate, teeth with rounded apices ( Fig. 9G ), not differentiated at the spiracle opening; 1 pair of anterior marginal setae ( Fig. 9C ) and 1 pair of posterior marginal setae present. Cephalothorax ( Fig. 9B ) about 0.5x the body length, separated from the latter by the transverse molting suture which extends to the submarginal region of the body, curving upwards distally; submedial region of the third thoracic segment with a pair of longitudinal sutures; submargin with a row of geminated porettes ( Figs. 9E, 9F ); a group of about 5 bright pores ( Fig. 9J ) present on the submarginal region. Submedial region of mesothorax and metathorax each with a pair of short setae, Ts2 and Ts3 setae equal in length ( Fig. 9B ). Metathoracic segment deeply incised medially. Abdomen ( Fig. 9H ) as long as the cephalothorax, with a well-defined, pronounced medial region, somewhat caterpillar-like in shape, with first abdominal segment much narrower, bowl-shaped and lacking As1 setae; rhachis present but arms not well defined; abdominal segment 8 with a pair of short, stout setae (As8) ( Fig. 9Q ); caudal setae ( Fig. 9A ) very long and stout, about 6.2x as long as As8 and 2.2x the length of the vasiform orifice ( Figs. 9K–9Q ), the latter cordate in shape, 1.1x as long as wide, surrounded by a narrow sclerotized rim; operculum nearly rectangular, 0.6x as long as wide, filling 0.4x the orifice, dorsal surface granulose with two transverse lines of tubercles, each line 6 to 7 tubercles; lingula ( Fig. 9L ) transparent with some micro setae at its apex. Venter ( Fig. 9I ) with high density of strongly chitinized microtubercles (mt), among them three white pores, adhesive sac (ad).

Adult Male ( Figs. 11A–11F )⸺Live, light brown in color due to the brown spots on the first pair of wings and the secretion of white wax. Freshly mounted in Hoyer, individuals show four pairs of reddish abdominal wax plates ( Fig. 11D ). The wings of A. martini are very similar to those of A. gratiosus in the shape and coloration of the forewing ( Fig. 11B ); however, the apex of the forewing of A. martini has a larger infuscate area and there are three distinct infuscate areas along the anterior margin. The hind wing of A. martini ( Fig. 11C ) is hyaline in the center with its base and apex lightly infuscate. Both males and females are similar in coloration, the body is predominantly pale with the head and wax plates slightly darker.

Adult female ( Figs. 11G–11N )⸺abdomen with only two pairs of abdominal wax plates of reddish color ( Fig. 11I ). The abdominal wax plates show little depressed dots lighter in color. The pattern of coloration of the wings is very similar to that of the male; metatibia with a comb of about 16 setae ( Fig. 11N ); genitalia normal ( Fig. 11J ); cement gland ( Fig. 11L ) with a bulb-like structure, apparently segmented in the form of a cluster of vesicles ( Figs. 11K–11L ). Antennae 7 segmented with a long sensorial cone that reaches the apex of segment III ( Fig. 11M ).

Biology

This species was collected from creole avocado trees in the El Bosque Country Club on the outskirts of Lima, Peru and has not been found so far on avocado trees within the urban perimeter of the city of Lima. It is the first species of whitefly that we are aware of that is known to excrete sulphureous yellow wax, which gives it a distinct appearance ( Fig. 9D ). It usually occurs on the underside of leaves in a dispersed form without forming large colonies, interspersed with other species of whitefly such as Aleurodicus juleikae , Tetralicia sawyeri and Paraleyrodes bondari . Their nymphal instars are pale in color and only the later immature stages are black.

Material examined

Holotype puparium, Club El Bosque, Lima-Peru, on Persea americana , slide with 25 puparia (holotype marked as specimen inside the red circle), 19/ix/2015, in NHM . Paratypes: Numerous puparia on nine slides, same data as holotype except collection date 24/09/2016 (7 puparia); 08/x/2015 (1); and 02/vii/2015 (1). One paratype slide deposited in each the USNM and UNALM, respectively, the rest of type material deposited in the collection of the first author. The paratypes are indicated with red circles .

Comments

Aleuroplatus martini is most similar to A. gratiosus , described on trees in the family Lauraceae in Brazil. Puparia of both species are black, are broadly oval in shape, have a strong rachis on the abdomen, the vasiform orifice is much longer than wide with the operculum filling only about half of the orifice, and excrete colored wax on their dorsum. According to Bondar (1923), A. gratiosus excretes 4 yellow pillars, which when observed with a lens are a soft, viscous, orange yellow color, while A. martini excretes sulfurous yellow wax. The puparia of Aleuroplatus gratiosus ( Fig. 10B, 10D ) and A. martini ( Figs. 10A, 10C ), show similarities and differences, which appear clearly in mounted specimens. The shape of the body contour, in A. gratiosus is in the form of a boat, whereas that of A. martini is oval. Both species secrete colored wax, A. gratiosus orange-yellow wax and A. martini sulfur yellow wax. This character serves to separate at least these 2 species from others that live among them on their host plant. The submarginal area of the puparium of A. gratiosus shows areas of lighter, rectangular shaped areas, regularly spaced throughout the body’s periphery, which are not present in A. martini . In addition, the two species differ in the sculpture of the dorsum of the operculum. In A. martini , this surface has a pair of transversal well-defined lines, each line with 6 to 7 tubercles; whereas A. gratiosus lacks these lines but shows fang-like structures of different sizes distributed in an irregular pattern. The operculum of A. martini ( Fig. 11C ) is trapezoidal whereas that of A. gratiosus is somewhat triangular ( Fig. 10D ).

A more detailed study was made of the operculum based on observations of 270 specimens mounted on 26 slides ( Figs. 9M–9P ). The operculum is a moveable part that opens and closes according to the individual’s need to excrete a sugary liquid (honeydew). The operculum of mounted specimens showed two different positions (opened and closed) which complicates their interpretation. When it is in the closed position, the dorsum shows two, well-defined transverse lines, each with 6 to 7 tubercles ( Fig. 9M ). When the operculum is in the open position (at close to 90º from the closed position), the tubercles on the dorsum can be seen in profile which shows that they are pyramidal and spine shaped ( Figs. 9B–9C ). The venter of the operculum is not observable in the closed position but shows spine-shaped structures in the open position ( Fig. 9D ). The results found leave open the possibility of investigating the function of these structures in the biology of this species. Observations of the A. gratiosus puparium were made only from one cotype specimen, deposited in the collection of the US National Museum (USNM). The contribution of this research on the variation of the morphology of the operculum when viewed from an open versus closed position addresses the need to study this structure in detail in individuals of A. gratiosus and other species.

Etymology

This species is dedicated to Dr. Jon Martin, who introduced the senior author to the study of the fascinating world of whiteflies.

Figures

FIGURE 1. A) Creole avocado trees in El Bosque club. Panoramic view of six trees (see arrows), showing differences in size, age and phenological status. While some are in the process of maturing fruits, others are beginning to flower and others are in the process of flowering and fruit set. B) generation of new Creole avocado trees in a ditch edge from seeds thrown by the club members, C) Tetralicia sawyeri n. sp. puparia on avocado leaves, D) detail of puparia on leaf, E) yellow coloration response of the avocado leaf around the body of nymphs and puparia of T. sawyeri n. sp., F) puparia of Aleuroplatus martini n. sp. on avocado leaves showing typical rods of yellow sulphureous wax on the underside of a leaf of creole avocado, G) detail of puparia with a drop of liquid above the waxy secretion, H) adults of Tetralicia sawyeri n. sp. on leaf.

FIGURE 9. Aleuroplatus martini n. sp.puparia.A) habitus, B) dorsum, C)cephalus, anterior marginal setae(ams), D) on avocado leaf, E–G) lateral margin, marginal pores (mp), H) abdomen, I) venter of cephalothorax, adhesive sac (ads), microtubercles (mt), J) cephalothorax, cluster of bright pores (bp), K–Q) vasiform orifice (vo)⸺K) sculpture of operculum, L) setae on lingula, M–P) different depths of field of vo, Q) As8 setae.

FIGURE 10. Puparia A) Aleuroplatus martini n. sp. habitus, B) A. gratiosus Bondar habitus dorsum, C) A. martini n. sp. vasiform orifice, D) A. gratiosus vasiform orifice at different depths of field.

FIGURE 11. Aleuroplatus martini n. sp. adults. A–G) adult male. A) habitus, B) forewing, C) hindwing, D) abdomen, wax plates (wp) four pairs, E) genitalia, F) claspers and aedeagus; G–N) adult female. G) habitus, H) habitus showing position of cement gland, I) abdomen wax glands (2 pairs), J) ovipositor, K–L) vesicles near ovipositor, M) antenna with photo detail of sensorial cone (sc), N) tibia III.