taxonID	type	description	language	source
03B387A5B91BFFF8FF43FF7A3EC8F95C.taxon	type_taxon	(Type species: Williamsrhizoecus baskyi, by monotypy.)	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFF8FF43FF7A3EC8F95C.taxon	description	Williamsrhizoecus baskyi Kozár & Konczné Benedicty, 2007: 355. Williamsrhizoecus coffeae Caballero & Ramos, 2018: 3. Williamsrhizoecus epicopus (Williams, 1970): 155. Williamsrhizoecus udzungwensis sp. n.	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFF8FF43FF7A3EC8F95C.taxon	diagnosis	Generic diagnosis. Body elongate oval. Antennae each with 5 or 6 segments; with 1 blunt sensory seta situated on penultimate antennal segment. Legs well developed. Dorsum and venter with trilocular pores. Multilocular disc pores present or absent. Oral collar tubular ducts absent. Tritubular pores present on dorsum and venter. With flagellate and clavate or falcate setae present on body surface, anal ring, legs, and antennae in varying combinations. Anal ring with oval to elongate pores, some with spicules, and 6 – 18 flagellate or clavate setae. Dorsal ostioles entirely absent, or only weakly developed if present. Circuli present or absent.	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFF8FF43FF7A3EC8F95C.taxon	discussion	Comments. Following Kozár & Konczné Benedicty (2007), this genus belongs to the subtribe Rhizoecina based on the presence of tritubular pores; the presence of clavate body setae distinguishes this genus from the others in the subtribe. Note, however, that the study of adult male morphology by Hodgson (2012) found little support for the subdivisions of Rhizoecini (now Rhizoecidae) proposed by Kozár & Konczné Benedicty. This casts some doubt on their decision to separate Ripersiellina from Rhizoecina, which was based on adult females having either bitubular or tritubular pores, respectively. The possession of blunt sensory setae on the penultimate antennal segment is not diagnostic for this genus, as originally described (Kozár & Konczné Benedicty 2007), as this feature is common throughout the family. The description of Williamsrhizoecus is here updated from the original account (Kozár & Konczné Benedicty 2007) to accommodate recent additions of species, including W. coffeae and the new species described here. The genus now includes species with 5 or 6 - segmented antennae (originally 5 - segmented only), with or without circuli (originally described as present), with or without multilocular disc pores (originally described as absent), with anal ring cells oval to elongate (originally described as elongate), and with 6 – 18 anal ring setae (originally described as having 6 setae). Caballero & Ramos-Portilla (2018) implied several of these changes when they described W. coffeae, but they did not explicitly revise the genus. The absence of dorsal ostioles is a rare, notable trait shared by all but one of the species comprising this genus. However, synapomorphies based on the absence of features are more equivocal than those based on presence. Kozár & Konczné Benedicty apparently regarded the presence of clavate setae on the anal ring as more critical to diagnosis, since they chose to recombine Neorhizoecus epicopus Williams into Williamsrhizoecus based on this trait, despite it being the only member of the genus to possess (weakly developed) dorsal ostioles. Williamsrhizoecus is evidently Gondwanan in origin, drawing on the known geographical distribution of the few species that comprise it, which includes Antigua and Barbuda, Colombia, Mexico, Tanzania, and Trinidad and Tobago. The rather disjunct distribution of species may reflect that root mealybugs are generally under-sampled, particularly in the Afrotropical region where only 33 out of 216 total species have been recorded (García Morales et al. 2016; last accessed 13. viii. 2020). It could also indicate artificiality of the genus, but this question would be best resolved with molecular evidence and morphological data from additional life stages that are unavailable at present.	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFFFFF43F88D3DEBFDA7.taxon	description	Fig. 1	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFFFFF43F88D3DEBFDA7.taxon	materials_examined	Material examined. Holotype adult female: TANZANIA: Udzungwa Mountains, attended by / colony of Acropyga silvestrii within nest / chambers, under rocks alongside a stream, / - 7.8449, 36.8835, 350 m; 27 March 2011; / J. S. LaPolla coll. (JSL 110327 - 04 A) (USNM). Paratypes: TANZANIA: 1 adult female, same data as holotype (JSL 110327 - 02 A) (USNM); 1 adult female, same data as holotype (JSL 110327 - 02 B) (USNM); 1 adult female, same data as holotype (JSL 110327 - 03 A) (USNM); 1 adult female, same data as holotype (JSL 110327 - 03 B) (USNM) (voucher ID: S 0430 A); 2 immature instars together on 1 slide, same data as holotype (JSL 110327 - 03 C) (USNM); and 1 adult female, same data as holotype (JSL 110327 - 04 B) (USNM).	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFFFFF43F88D3DEBFDA7.taxon	description	Description of adult female (N = 6). Mounted on microscope slide, body approximately oval and membranous throughout, 0.88 – 0.95 mm long, 0.64 – 0.73 mm wide, widest near abdominal segment II. Abdomen gently tapering toward posterior end; abdominal segment VIII approximately 250 μm wide at base. Anal lobes poorly developed, indicated by slight protrusions of the body margin, each lobe with a cluster of several dorsal clavate setae, each seta 10 – 18 μm long. Anal ring dorsal, located slightly anterior of body apex, with two concentric rows of ovoid cells, some lateral cells each bearing a spicule. Anal ring setae arranged in 9 pairs, numbering 18 in total, each seta approximately 19 – 24 μm long. Antennae 6 - segmented, situated close to each other on ventral submargin of head. Stout flagellate setae present on each antennal segment, 12 – 21 μm long; with 1 falcate sensory seta present on segment V and 3 falcate sensory setae present on segment VI. One sensory pore and two seta-like sensillae present on antennal segment II. Average antennal segment lengths in μm: I – 32, II – 19, III – 16, IV – 12, V – 13, VI – 38; overall length 130 μm. Eyes absent. Dorsal ostioles absent. Labium 3 - segmented, 76 μm long and 48 μm wide, with few short flagellate setae present on each segment. Cephalic plate absent. Legs well developed; hind leg average length measurements in μm: trochanter + femur 108; tibia + tarsus 129. Ratio of lengths of metatrochanter + femur to tibia + tarsus, 0.84; ratio of lengths of metatibia to tarsus, 1.39. Hind tarsus widest at base and tapering to claw, about 24 μm long. Claws with simple digitules, shorter than the claw, and without denticles. Several flagellate setae present on each leg segment, about 15 setae present on each hind tibia. Spiracles normal for the family, each approximately 23 μm in diameter at widest point. Circulus absent. All body setae on dorsum and venter clavate to falcate, 8.5 – 10 μm long, either linear or curved, widest at tip or widest just proximal to tip and tapering distally. Setae arranged in irregular rows separated by bald intersegmental regions, otherwise fairly evenly distributed throughout. Trilocular pores numerous across dorsum and venter, interspersed with setae. Tritubular pores also numerous on both dorsum and venter, though less common than trilocular pores; arranged in singular transverse rows toward the midline or posterior edge of each segment, those on dorsum of abdomen mostly located medially to submarginally, those on venter of abdomen mostly located marginally to submarginally, except for segment VII, where they extend from midline to margin. Multilocular disc pores absent.	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFFFFF43F88D3DEBFDA7.taxon	discussion	Comments. Williamsrhizoecus udzungwensis sp. n. is similar to W. coffeae in that they both possess 6 antennal segments, lack ventral abdominal circuli, and have clavate body setae. However, in W. udzungwensis sp. n. (Fig. 1) the body setae are short and thickened throughout the length of the seta, sometimes curved and appearing falcate (sickle-shaped), whereas in W. coffeae the body setae have a longer flagellate stem that terminates in a dilated tip. The same trait distinguishes W. udzungwensis sp. n. from W. baskyi, which is also from Tanzania. Additionally, whereas W. udzungwensis sp. n. lacks circuli and has six antennal segments, W. baskyi has two circuli and only five antennal segments. There are similarities between W. udzungwensis sp. n. and the only other rhizoecid confirmed to associate with Acropyga in the Old World (Tanaka 2016), Ishigakicoccus shimadai Tanaka. Besides the obvious ecological connection, both species lack dorsal ostioles and both have body setae that could be described as clavate. The body setae of I. shimadai are mostly flagellate and hooked at the apex, but rarely they are knobbed at the apex (Tanaka 2016), suggesting a potential affinity to Williamsrhizoecus. Tanaka considered Ishigakicoccus as being similar to Capitisetella and Pseudorhizoecus because they all lack dorsal ostioles, but did not consider Williamsrhizoecus in his discussion, which differs from the other genera by having tritubular pores. Tanaka used the presence of two types of wax pores in Ishigakicoccus, small pores with 6 loculi surrounding a central chamber and large 3 – 5 locular pores without a central chamber, as justification for establishing a new genus (Tanaka 2016). These structures are distinct from the multilocular disc pores found in Williamsrhizoecus, which are present only in W. coffeae. Acropyga workers were observed actively carrying individuals of W. udzungwensis sp. n. around within the nest-box and gathering them together into small chambers that the workers had excavated from loose soil. The behavior of arranging root mealybugs into protected clusters is a critical observation of direct association. No mating swarms of A. silvestrii were observed, so trophophoresy of W. udzungwensis sp. n. (transportation of gravid females by A. silvestrii queens) cannot be confirmed at present. Prior to this study, the only known root mealybug association with an African Acropyga species was between A. arnoldi Santschi and the xenococcid, Eumyrmococcus scorpioides (De Lotto) (Prins 1982; LaPolla & Spearman 2007). Eumyrmococcus williamsi Kozár & Konczné Benedicty also occurs in Tanzania, in the Uluguru Mountains, but the Acropyga species associated with this xenococcid was not recorded at the time of its collection (Kozár & Konczné Benedicty 2007). Eumyrmococcus williamsi was later found to associate with a new species of Acropyga (JSL manuscript in preparation). Interestingly, the neighboring Udzungwa and Uluguru Mountain ranges each harbor a distinct Acropyga species partnered with a root mealybug. Ecological associates. Acropyga silvestrii Emery (Hymenoptera: Formicidae); W. udzungwensis sp. n. was feeding on roots, host plant not recorded.	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
03B387A5B91BFFFFFF43F88D3DEBFDA7.taxon	etymology	Etymology. The specific epithet is an adjective formed from Udzungwa, the mountain range where it was discovered, together with the Latin suffix - ensis, meaning of or from a place.	en	Schneider, Scott A., Lapolla, John S. (2020): Trophobiosis between a new species of Williamsrhizoecus (Hemiptera: Coccomorpha: Rhizoecidae) and Acropyga silvestrii (Hymenoptera: Formicidae) in Tanzania. Zootaxa 4853 (2): 283-291, DOI: 10.11646/zootaxa.4853.2.9
