Bryophaenocladius palmerparcum Namayandeh & Hudson, 2024

Namayandeh, Armin, Guerra, Sergio, Islam, Natasha, James, Taylor, Hudson, Patrick L., Ghaderi, Edris, Yusuf, Thameena, Vasquez, Adrian A. & Ram, Jeffrey L., 2024, New species and a fascinating diversity of Chironomidae (Diptera, Insecta) in and around an overlooked urban vernal pool, ZooKeys 1208, pp. 133-163 : 133-163

Bryophaenocladius palmerparcum Namayandeh & Hudson sp. nov.

Fig. 7 A – D

Type material.

Holotype 1 male; USA, Michigan, Detroit, Palmer Park, Pond A ; 42.42766 ° N, 83.11741 ° W; leg. P. L. Hudson; 30. vi. 2022, dep. ARC . Paratypes 2 males; same as holotype except leg. A. Namayandeh; 28. vi. 2023, dep. ARC .

Diagnostic characters.

The adult male of B. palmerparcum sp. nov. can be distinguished from other Bryophaenocladius Thienemann, 1934 males by the combination of the following characters: AR 1.4–1.5; costa not well-extended; anal point short, wide, and triangular, not surpassing the apex of tergite IX, with 11–15 setae; virga inconspicuous, consists of two long spines, looped; sternapodeme straight without large oral projections; superior volsella collar shaped; inferior volsella absent; gonostylus straight with a mid-section wide, and short collar-shaped crista dorsalis ; HR 1.5–1.9; HV 2.6–2.9.

Description.

Male (n = 3; unless otherwise stated). Total length 2.7–3.4 mm, Wing 1.4–1.7 mm long and 0.4 mm wide.

Coloration. Head, abdomen, and halter dark brown. Thorax dark brown with much paler yellowish areas in portion of dorsocentrals, in anteprontal, anepisternum, and apical portion of preepisternum regions. Legs golden brown. Wing greyish brown.

Head (Fig. 7 A, B ). Antenna with 13 flagellomere, last flagellomere with 10 sensilla chaetica, each of 2 nd and 3 rd flagellomere with pair of sensilla chaetica; shaft starts at base of 4 th flagellomere (Fig. 7 A ); AR 1.4–1.5. Temporal setae 9, uniserial. Tentorium 150–190 µm long, tentorial pit close to apex. Clypeus squared, 101 µm long and 125 µm wide, with 20 setae, setae 73 µm long (n = 1). Palpal segments lengths (in μm): 55–77, 66; 33–57, 45; 157–164, 161; 125–131, 128; 93, third palpomere with 3 sensilla clavata, and without any projection.

Thorax (Fig. 7 C ): Achrostichals 8–10, starting close to antepronotum; dorsocentrals 12–23, 18 in two rows; prealars 4–6, 5; scutellars 12; antepronotals 3 basoventrally.

Wing (Fig. 7 D ): Brachiolum with 2 setae; R with 7–13, 10 setae; R 1 with 4 setae; R 4 + 5 with 4 setae; other veins bare. Squama with 7–8 setae. Anal lobe produced and squared. Costa not well-extended, 17–20, 18 µm long. Microtrichia visible at 10 × magnification.

Legs. Foreleg spur 58 μm long (n = 1), midleg spur 30 μm long (n = 1), other spur damaged; hindleg spurs damaged, hind tarsus missing, hindleg comb with 12 spines (n = 1). Lengths and proportions of legs as in Table 2 .

Hypopygium (Fig. 7 E ): Anal point short, wide, and triangular, not surpassing the apex of tergite IX, 18 μm long and 34 μm wide at the base (n = 1), surface with 11–15, 12 setae. Virga inconspicuous, consists of two long spines, looped, 58 μm long (n = 1). Sternapodeme straight with large oral projections, 84–104, 97 μm long. Phallapodeme 42–50, 45 μm long. Superior volsella collar shaped, inferior volsella absent. Gonocoxite 158–216, 187 μm long. Gonostylus straight with a mid-section wide and short collar-shaped crista dorsalis , gonostylus 102–114, 110 μm long, megaseta 9 μm long. HR 1.5–1.9, 1.7; HV 2.6–2.9, 2.8.

Female and immatures. unknown.

Etymology.

The species is named after the locality where it is found, Palmer Park. The word parcum is Latin, meaning park.

Distribution.

USA (Michigan).

Remarks.

A combination of strong decumbent achrostichals close to antepronotum; bare wing with strong punctation of microtrichia, and weak lateral spines attached to the shaft of hind and mid legs spines places this species in Bryophaenocladius . Although, in general, the long, prominent, and hyaline anal point defines many known species of Bryophaenocladius , the character of the short anal point of this species is not uncommon, and it has been observed among other known species of this genus. Previously, Donato et al. (2024) have demonstrated that the species of Bryophaenocladius show a significant pattern of anal point size and shape differences. For instance, among those species with short anal points, Bryophaenocladius scleras Wang, Liu & Epler, 2012 from the Nearctic has a short semicircular anal point (see Wang et al. 2004), and Bryophaenocladius pleuralis (Malloch, 1915) has a dark short anal point that does not extend beyond tergite IX ( Makarchenko and Makarchenko 2009). Additionally, Epler (2012) described brachypterous Bryophaenocladius chrissichuckorum with a wide and short, triangular anal point similar to that of B. palmerparcum sp. nov. The first author has also observed this character of short anal point in Neotropical species (AN pers. obs. of specimens from Costa Rica). What is also observable is that besides the variation in shape and size of the anal point, as discussed in Donato et al. (2024), those species with the short anal point can still possess the hyaline section, such as Bryophaenocladius inconstans Brundin, 1947 and some lacking, such as the case of B. palmerparcum , B. chrissichuckorum and B. pleuralis . Therefore, the presence of an anterior hyaline section of the anal point can also separate species with a reduced anal point.

Figures

Figure 7. Bryophaenocladius palmerparcum sp. nov., adult male A antenna B head C thorax D wing E hypopygium. Scale bars: 100 µm.