Phthinia mikmaqi Fitzgerald & Kerr

Fitzgerald, Scott J. & Kerr, Peter H., 2014, Revision of Nearctic Phthinia Winnertz (Diptera: Mycetophilidae), Zootaxa 3856 (3), pp. 301-325 : 313-315

Phthinia mikmaqi Fitzgerald & Kerr n. sp.

Figs. 20–24

Type material. Holotype: ♂ ( Fig. 20 ) [ CNCI], “Mount Uniacke, N.S. 5.VIII.1958, J.R. Vockeroth” / “ HOLOTYPE 13N263, Phthinia mikmaqi ♂, Fitzgerald & Kerr, 2014 ” [red label], mounted directly on side of pin, nearly complete specimen, missing part of left front leg, terminalia dissected.

Etymology. This species is named after the First Nations people, Mi’kmaq, whose territories include the Canadian Maritime Provinces where this species was found. The Mi’kmaq people are politically active, and fight to protect clean water and other natural resources in New Brunswick from “fracking” and other polluting forms of land exploitation. The Mi’kmaq people are an inspiration for environmental engagement worldwide.

Diagnosis and comments. In the Nearctic region, P. mikmaqi n. sp. is most similar to P. neptunei n. sp., but can be distinguished by the bilobate gonostylus in P. mikmaqi n. sp. and trilobite gonostylus in P. neptunei n. sp. See also “discussion” section below.

Description. Male ( Fig. 20 ). Head dark brown, abdomen brown, remainder light brown except for coxa light brown to cream colored. Body length: [5.4] mm (n=1). Head. First flagellomere longer, approximately 1.6 times the length of flagellomere 2. Thorax. Laterotergite bare. Scutellum with 2 stronger bristles. Legs. First tarsomere of anterior leg about 1.5x length of foretibia, first tarsomere of midleg about 0.9x as long as midtibia, and first tarsomere of hind leg about 0.7x as long as hind tibia. Hind tibia with 9–11 minute anterior setae, 34 minute dorsal setae (n=1), and posterior setae absent (n=1); midtibia also with minute setae. Wings. Length: [4.6] mm (n=1). Membrane with microtrichia present between dense macrotrichia. C extending about 1/4 of the distance between R5 and M1; Rs about 1/5-1/4 length r-m; medial fork complete; M1 not faint basally; stem of medial fork approximately 3/5 length of r-m. A1 diverging greatly from stem of CuA. Abdomen. Terminalia ( Figs. 21–24 ). Terminalia previously dissected making color indeterminable. Cerci and hypoproct forming two pairs of setose lobes dorsal to parameres ( Fig. 21–22 ). Gonocoxites with dense brush-like setae on inner dorsoapical surface beyond gonostylar articulation ( Figs 22–23 ). Gonocoxites ventroapically developed into a pair of dark, heavilysclerotized, short, stout, apically broadly-rounded, medially curved lobes ( Figs. 22–24 ). Gonostylus articulating dorsally on gonocoxite; gonostylus elongate, slightly curved, bilobate; the smaller sub-basal lobe short, thumb-like, apically tapered, narrowly apically rounded, and the longer (primary) lobe apically expanded, spatulate, with a single strong preapical seta just anterior to spatulate expansion ( Figs. 22–23 ). In ventral view aedeagal complex triangular, strongly tapered apically, apically acute ( Fig. 24 ). Posteroventral margin of gonocoxites difficult to discern, but apparently with median, mound-like, hypandrial lobe ( Fig. 24 ).

Female. Unknown.

Discussion. P. mikmaqi n. sp. is most similar to the Eastern Palearctic species P. amurensis Zaitzev (1994) and, based on available information, is indistinguishable from this species. The illustration of the male terminalia of P.

amurensis provided by Zaitzev (1994: plate 56, fig. 5) is in ventral view, and does not show the structure of the gonostylus, which is often diagnostic for Phthinia species. Zaitzev’s description also makes no mention of the structure of the gonostylus and the type of P. amurensis was unavailable for study. There are several examples in Nearctic Phthinia where, based on the structure of the male terminalia, the most similar species happens to be a Palearctic one (for example, P. hyrcancica Zaitzev / P. neptunei n. sp., P. lenae Zaitzev / P. tanypus , P. congenita Plassmann / P. meicigama n. sp.). Considering this pattern, it is quite possible that P. am u re n s i s and P. mikmaqi n. sp. represent another example of such a Palearctic / Nearctic species pair that have similar, but distinct male terminalia. Though the lack of solid information about the terminalia of P. amurensis prevents further evaluation, this pattern of species pairs, and the fact that no other species of Phthinia have yet been found to be Holarctic, leads us to conclude that P. mikmaqi n. sp. is a distinct taxon and we have decided to treat it as such until further information suggests otherwise.

Figures

FIGURE 20. P. mikmaqi n. sp., habitus [holotype male, # 13 N 263]. Scale bar = 1 mm.

FIGURES 21 – 24. P. mikmaqi n. sp., male terminalia [holotype specimen, # 13 N 263]. 21. Lateral view. 22. Posterior view. 23. Dorsal view. 24. Ventral view. Scale bar = 0.1 mm.