Barbenigma Powell & Miller, 2024

Powell, Erin C., Miller, Douglass R. & Keller, Oliver, 2024, Barbenigma Powell & Miller, a bizarre new genus and two new species of scale insects (Hemiptera: Coccomorpha: Ortheziidae) from the United States, Zootaxa 5529 (2), pp. 293-317 : 296-297

Genus Barbenigma Powell & Miller , gen. nov.

Type species: Barbenigma biza Powell & Miller sp. nov. by current designation.

Diagnosis: Adult female with a combination of the following characters: antennae each three-segmented, apical and subapical setae differentiated. Legs reduced in size, tibia and tarsus not fused, trochanter with two campaniform sensilla on each surface, trochanter and femur fused. Ovisac band modified. Wax plates, multilocular pores, and eyes absent. With three pairs of abdominal spiracles, atria of both thoracic and abdominal spiracles each with ring of raised pores. Abdomen with eight quadrilocular duct and spine clusters. Setae on dorsum and margin robust and fimbriate, spines on dorsum and margin each with swollen rounded apices, setae and spines reduced in number.

Notes: Barbenigma species are similar to the four species previously placed in the Carayoneminae in having: trochanters each with two campaniform sensilla on each surface, trochanter and femur fused, tibia and tarsus separate; dorsal setae ornate fimbriate; labium small and rotund; antennae each three-segmented, each with enlarged apical and subapical setae; and eyes absent. Barbenigma species have (shared contrasting character states in species of Baloghicoccus Kozár , Carayonema Richard , Foldicoccus Kozár , and Mahunkacoccus Kozár are given in parentheses): compound duct clusters of quadrilocular pores (quadrilocular duct clusters absent); without bilocular pores (with bilocular pores); with spines (without spines); ventral thoracic spiracles, each with pores in atrium (dorsal thoracic spiracles, each without pores in atrium); with tubular ducts (without tubular ducts); and with dome-shaped or acorn-shaped setae (with flagellate setae).

The species of Barbenigma do not fit in any of the currently known subfamilies of Ortheziidae .

Barbenigma species are similar to the Australian ortheziid ant inquiline A. williamsi in having: eyes absent; a reduced or absent ovisac band; no wax plates; a reduced number of antennal segments; and two campaniform sensilla on each surface of the trochanter. However, Barbenigma species have ( A. williamsi character states in parentheses): three-segmented antennae (two-segmented); atria of thoracic and abdominal spiracles each with ring of pores (spiracular atria without pores); ventral clusters of quadrilocular pores and spines on abdomen (ventral quadrilocular pores present singly); few dorsal spines scattered over body (densely covered in spines); ventral spines absent except marginally and in pore clusters (entire venter densely covered in spines); and anal ring well developed with pores, situated at apex of abdomen (anal ring without pores, situated at center of body).

The ortheziid subfamily Newsteadiinae , which includes only the genus Newsteadia Green 1902 (62 species), is defined by ( Barbenigma species character states presented in parentheses): first antennal segment conspicuously larger than other antennal segments (antennal segments about equal); dorsal wax lobes present (dorsal wax lobes absent); tubular ducts on dorsum between wax spines (tubular ducts present on dorsum but wax spines sparse); and venter without a band of spines inside ovisac band (ovisac band heavily modified). Barbenigma species resemble Newsteadia in having: tubular ducts with four loculi, these probably modified quadrilocular pores; tarsus longer than tibia; and tubular ducts on dorsum. Some species of Newsteadia also have three-segmented antennae. However, the new genus differs in having ( Newsteadia characters given in parentheses): thick differentiated apical seta on apical antennal segment (hair-like apical seta on apical antennal segment); apical segment of antenna about equal to other segments (apical segment conspicuously larger than other segments); and tibia and tarsus separate (tibia and tarsus fused or only partly separated by fine suture).

Barbenigma species and members of the subfamily Ortheziinae are similar in having tibia and tarsus separate but differ in having ( Barbenigma species character states in parentheses): distinctive short, stout apical setae on terminal antennal segment (apical setae long, exceeding length of apical segment); and presence of two enlarged spines on tibia (enlarged spines on tibia absent). Barbenigma species bear some similarity to certain species of the ortheziine tribe Arctortheziini , which includes only the genus Arctorthezia Cockerell, 1902 , in having a series of circular clusters of pores on margin and spiracles with associated pores. However, Barbenigma species have eight ventral duct clusters, containing modified quadrilocular pores and spines, on margin and median area of abdomen, whereas Arctorthezia species with pore plates (e.g., Arctorthezia pseudoccidentalis Morrison, 1925 and A. vardziae Hadzibejli, 1963 ) have between 16–18 dorsal pore plates, each consisting of simple pores without loculi around body margin, sometimes extending up to thorax and head. Arctorthezia is a more typical ortheziid with ( Barbenigma species character states are presented in parentheses): 7–8 antennal segments (antennae three-segmented); large eyes (eyes absent); body densely covered in spines (spines sparse); and with an ovisac band (ovisac band absent). The tribe Ortheziini is defined by having ( Barbenigma species character states are in parentheses): tibia and tarsus bearing hair-like setae dorsally and spine-like setae ventrally (bearing spine-like setae dorsally and hair-like setae ventrally); and thoracic spiracles without pores (with a ring of pores).

Barbenigma species are similar to members of the ortheziid tribe Mixortheziini in having a reduced number of antennal segments and short anal-ring setae. However, the Mixortheziini have an ovisac band, typical elongate legs, and the eye present. Some Mixorthezia Morrison, 1925 species have large bare areas on the dorsum similar to Barbenigma species but this feature is seemingly not restricted to any one subfamily (e.g., Orthezia nuda Ferris 1919 in Ortheziinae ).

Barbenigma species and the ortheziid tribe Nipponortheziini are similar in having reduced antennal segments (usually three) but differ in having ( Barbenigma species character states in parentheses): long antennal segments (short antennal segments); eyes present (eyes absent); large, elongate labium (short, rotund labium); and wax plates present (wax plates absent).

Barbenigma species are seemingly unrelated to the subfamily Ortheziolinae , which is defined by ( Barbenigma species character states are presented in parentheses): a well-developed pseudobasal segment at the base of the antennae (no pseudobasal segment); three setae inserted in one basal socket on the labium (all setal sockets with only one seta); sclerotized plate anterior to anal ring (sclerotized plate absent), and claw digitule setiform (claw digitule spiniform). The Ortheziolinae also are defined by having ‘thumb-like pores’ on each side of the anal ring but it is unclear whether the dome- and acorn-shaped setae concentrated in a cluster on the head of Barbenigma could be homologous.

Etymology: The genus name Barbenigma is from the abbreviated name “ Barb ” (from Barbara) and the suffix “ enigma ”. The name serves as a dedication to Barbara Denno. She has contributed immensely to the coccidology community through her tireless dedication to ScaleNet and has supported DRM in his extensive collecting trips, including the trip on which the holotype of B. boscus was collected. Moreover, the given name Barbara is derived from the Greek “ barbaros ”, meaning “stranger” or “foreign”. This comparison is fitting for a scale insect for which the family placement has been puzzling. The ending “ enigma ” is Greek for a riddle, or something or someone that is a puzzle or a mystery. The name is a neuter noun.