Metacnephia phrygiensis, Şirin, Umit D. & Adler, Peter H., 2015

Şirin, Umit D. & Adler, Peter H., 2015, Chromosomal and morphological taxonomy of a new species of black fly in the genus Metacnephia (Diptera: Simuliidae) from Western Anatolia, Turkey, Zootaxa 4048 (2), pp. 269-280 : 270-279

publication ID	https://doi.org/ 10.11646/zootaxa.4048.2.7
publication LSID	lsid:zoobank.org:pub:F8DBCC50-E7E9-434D-8200-A12292CC8085
DOI	https://doi.org/10.5281/zenodo.6108207
persistent identifier	https://treatment.plazi.org/id/4F0F87F5-4A14-DB2E-FF47-FB07FB90CCA4
treatment provided by	Plazi
scientific name	Metacnephia phrygiensis
status	sp. nov.

Treatment

Metacnephia phrygiensis new species

( Figs. 1–8 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 )

FEMALE. General body color brown to dark brown; all hair silvery to pale golden.

Head —Frons about twice as long as narrowest width; head about 6 times wider than narrowest width of frons. Antenna with 9 flagellomeres; pedicel subequal in width to and about 1.1 times longer than first flagellomere. Maxillary palp ( Fig. 1 View FIGURE 1 A) slender; palpomere III about 1.5 times longer than wide, and about 1.8 times longer than sensory vesicle; mouth of sensory vesicle about 1/4 length of its body; palpomere V about 1.5 times longer than III. Lacinia with 15 retrorse teeth, plus 6–8 blunt serrations. Mandible ( Fig. 1 View FIGURE 1 C) with 32 small teeth on inner margin and 13 larger teeth on outer margin. Cibarium with anterior margin broadly concave, without teeth.

Thorax —Length 1.7–1.8 mm (n = 4). Scutum with 3 faint, narrow, grayish pollinose, longitudinal vitae, conspicuous with removal of scutal hair. Scutellum laterally with long, dense, anteriorly directed hair. Anepisternal membrane with tuft of hair on upper half. Wing length 3.7–4.1 mm. Subcosta with single row of setae ventrally. Radius entirely haired dorsally; R1 dorsally with minute, black, spiniform setae on apical half. Halter whitish, with stem straw colored. Legs concolorous, slightly paler than body. Hind basitarsus parallel-sided, slender, 6.4 times longer than wide. Calcipala minute, as long as wide, bluntly pointed; pedisulcus nothing more than trace of elongated depression with minimal wrinkling. Claws bifid ( Fig. 3 View FIGURE 3 A), each with well-developed thumblike lobe extended about half distance to tip of talon.

Abdomen —Segments laterally with dense, long hair. Cercus ( Fig. 2 View FIGURE 2 A) in lateral view subrectangular, about 2.4 times wider than long, broadly rounded posteriorly. Anal lobe ( Fig. 2 View FIGURE 2 A) in lateral view consisting of unpigmented apical lobe with well-sclerotized, pigmented anteroventral margin, without microsetae but with macrosetae, plus pigmented, micro- and macrosetose basal portion narrowed and extended dorsally. Hypogynial valve subtriangular, with narrow, pigmented, well-sclerotized medial margin parallel to that of opposite valve. Genital fork ( Fig. 2 View FIGURE 2 B) slender, as thick as each arm at junction, about as long as arm plus lateral plate; lateral plate narrow, well sclerotized centrally along its longitudinal axis, bearing short, anteriorly directed apodeme. Spermatheca darkly pigmented, ovoid, about 1.4 times longer than wide, 70–78% length of stem of genital fork; cuticle internally with strongly expressed polygonal pattern (cf. fig. 17 of Evans & Adler 2000); junction with spermathecal duct unpigmented.

MALE. General body color brown to blackish, much like female but darker; all hair silvery to pale golden, distributed as in female but typically longer.

Head —Antenna with 9 flagellomeres; first flagellomere slightly narrower, and about 1.2–1.4 times longer, than pedicel. Maxillary palp ( Fig. 1 View FIGURE 1 B) slender; palpomere III about 2 times longer than wide, and about 3 times longer than sensory vesicle; mouth of sensory vesicle less than 1/3 length of its body; palpomere V about 1.5 times longer than III. Mandible weakly sclerotized, untoothed, with slightly ragged margin apically ( Fig. 1 View FIGURE 1 D).

Thorax —Length 1.7–1.8 mm (n = 4). Scutum blackish, subshiny, unpatterned at all angles of light. Anepisternal membrane with tuft of hair on upper half. Wing length 3.4–3.9 mm. Subcosta with single row of minute setae ventrally on at least apical half. Radius entirely haired dorsally; R1 dorsally with minute, black, spiniform setae on apical one third. Halter brownish. Legs concolorous, paler than body. Fore basitarsus parallel sided, slender, 10 times longer than wide. Hind tibia slightly flattened, 4.6–4.7 times longer than greatest width. Hind basistarsus nearly parallel sided, 4.2 times as long as wide. Calcipala and pedisulcus as for female.

Abdomen— Genitalia: Gonocoxite subquadrangular ( Fig. 2 View FIGURE 2 C). Gonostylus in ventral view ( Fig. 2 View FIGURE 2 C) about 2.6 times longer than basal width, smoothly and gradually curved and tapered toward apex, with 1 small apical spinule; in lateral view ( Fig. 2 View FIGURE 2 D) tapered, with apical 1/4 strongly curved medially. Ventral plate in ventral view in situ ( Fig. 2 View FIGURE 2 C) with body about 1.3 times wider than long, broadly rounded posterolaterally, with posterior margin slightly concave medially, and anterior margin between arms straight to slightly concave; in lateral view ( Fig. 2 View FIGURE 2 E), slender, slightly bowed, with lip gradually protruded apically; in ventral view tilted slightly posterodorsally ( Fig. 2 View FIGURE 2 F) markedly concave and broadly rounded posteriorly. Dorsal plate ( Fig. 2 View FIGURE 2 G) lightly sclerotized, about 5 times wider than long, with anteromedial notch. Median sclerite ( Fig. 2 View FIGURE 2 H) expanded basally, narrowed and parallel sided in middle section, with apical bifurcation folded back on itself. Paramere subtriangular, connected by slender extension to series of about 30 spines. Aedeagal membrane with comblike rows of microspines.

PUPA. Total length (without gill) 4.9–5.9 mm, mean 5.4 mm (n = 10).

Head ( Fig. 3 View FIGURE 3 B)—Cuticle with irregularly scattered, rounded microtubercles. Frontoclypeal sheath bearing 1 small, slender, unbranched trichome along medial antennal margin per side.

Thorax ( Fig. 3 View FIGURE 3 C)—Cuticle with microtubercles as on head; 3 or 4 slender, unbranched trichomes dorsally per side. Gill ( Fig. 3 View FIGURE 3 D) with 46–53 fine, slender, grayish, transversely furrowed filaments arising from 3 short, stout, medial stalks and 1 outer cluster variously branched directly from base; dorsal group with 16 or 17 filaments, middle group with 6–8 filaments of which 2 are thickest in gill, ventral group with 8 filaments, and outer cluster with 16–20 filaments.

Abdomen— Tergite I with 3 small, pale setae per side; II with 4 dorsal and 3 or 4 lateral, small, dark brown setae per side; III and IV each with 1 small seta at about midlength and 4 dorsal and 3 lateral, anteriorly directed, recurved hooks along posterior margin per side; V with same onchotaxy as III and IV, but with 3 lateral anteriorly directed tiny hooks in pleural membrane rather than in tergite; V–VIII each with dark brown spine comb along anterior margin, progressively enlarged on each segment ( Fig. 3 View FIGURE 3 E, F); VI and VII with 2–5 minute, pale, thin setae in pleural membrane per side, plus 1 anteriorly directed hook on sclerite in pleural region; IX with pair of brown, acuminate, posteriorly directed terminal spines. Sternites III and IV with 3–5 small, slender, brown setae per side. Segment V with 0–2 small, pale setae in pleural membrane and pair of closely set anteriorly directed, recurved hooks on sternite per side. Segments VI and VII each with 0–2 small, pale setae, and 1 brown, anteriorly directed, recurved hook in sternite; segment VIII with 2 or 3 brown, anchor-shaped hooks in pleural membrane per side; IX with lateral cluster of 4–6 anchor-shaped hooks, each bearing 2–6 tines, in pleural membrane of each side ( Figs. 4 View FIGURE 4 A, B).

Cocoon —Total length 7.6–9.7 mm, mean 8.3 mm (n = 8). Slipper shaped, elongated, low in profile, coarsely woven, fenestrated, especially in anterior 1/3 where windows are enlarged ( Fig. 4 View FIGURE 4 C), anterodorsally often incised for 1/4–1/3 total cocoon length.

LARVA (mature). Length 8.1–9.3 mm, mean 8.8 mm (n = 14). General body color brownish gray; intersegmental bands thin, unpigmented.

Head —Head capsule pale yellowish ( Fig. 5 View FIGURE 5 A, B); head spots generally positive, brownish, but variably and weakly defined; anteromedial and posteromedial head spots confluent or nearly so, forming continuous longitudinal line, sometimes confluent with first anterolateral head spots, forming cross, and sometimes with second posterolateral head spots, forming continuous posterior border across frontoclypeal apotome; second anterolateral head spots confluent with first or absent; first posterolateral head spots variably distinct; setae on frontoclypeal apotome minute, unbranched, sparse, fewer than 25 posterior to antennal bases, and those on postgena unbranched or bifurcated basally (visible only with transmitted light through cleared head capsule and partially closed stage diaphragm; Fig. 5 View FIGURE 5 B, D); line above ocelli brown. Cervical sclerites ovoid, free from postocciput or connected to it laterally by strip of barely pigmented cuticle. Antenna subequal in length to stem of labral fan; proximal article pale brownish dorsally; medial article nearly unpigmented; distal article uniformly brown, contrasting strongly with medial article; ratio of articles (proximal to distal including apical sensillum) approximately 1.0:1.5:1.0. Labral fan short, stout, with 54–60 (n = 10) primary rays; microtrichia long, up to 40 µm. Hypostoma ( Fig. 4 View FIGURE 4 D) with all teeth minute; each lateral tooth inclined medially; 4–6 lateral serrations per side; 3–5 unbranched or apically bifurcated hypostomal setae along each lateral margin, plus 1 or 2 additional, smaller, branched or unbranched setae on central disk. Mandible bearing 2 somewhat lobate outer teeth, 1 large apical tooth, about 12 slender spinous teeth, and 3–5 mandibular serrations (sensu Craig 1977) ( Fig. 4 View FIGURE 4 E). Postgenal cleft ( Fig. 5 View FIGURE 5 C, D) triangular, with lateral margins variably bowed outward, and with slender extension of variable apparency continued toward or to hypostomal groove; subesophageal ganglion at least partially ensheathed with grayish pigment.

Thorax —Prothoracic proleg with lateral plate pale yellowish brown to brown, subquadrangular. Gill histoblast (dissected out and uncurled, cf. Fig. 3 View FIGURE 3 D) of 46–53 slender filaments arising from 3 short, stout, medial stalks and 1 outer cluster variously branched directly from base; dorsal group with 16 or 17 filaments, middle group with 6–8 filaments of which 2 are thickest in gill, ventral group with 8 filaments, and outer cluster with 16–20 filaments.

Abdomen —Segments gradually expanded posteriorly, widest at segment VII; ventral tubercles absent. Cuticle nearly bare. Anal sclerite with anterior arms broadened at midlength; posterior arms slender, and about 1.3–1.4 times longer than anterior arms. Rectal papillae of 3 unbranched lobes. Posterior circlet with 98–102 rows of 13–15 hooklets each.

Polytene chromosomes. The polytene complements (2 n = 6) of 15 larvae (10 females, 5 males) were analyzed from the type locality in April of 2007 (11 larvae) and 2008 (4 larvae). The complement had the typical whole-arm interchange (IS + IIL, IL + IIS) characteristic of the genus. The homologues were tightly paired for about 85–90% of the total complement length, the centromere regions were expanded, and the nucleolar organizer was in the standard location in the base of IS.

Chromosome arms IS and IIIS had the standard banding pattern of the genus. IIS was fixed for inversion IIS-2 and IIL was fixed for IIL-6, both of Procunier (1982). IL is hypothesized, perhaps overly simplistically, to have a single, fixed, mid-arm inversion, IL-12 ( Fig. 6 View FIGURE 6 ), and IIIL to have 4 fixed inversions— IIIL-6 (which is an autosomal polymorphism in M. amphora Ladle & Bass ; Procunier 1982), IIIL-8, IIIL-9, and IIIL-10 ( Fig. 7 View FIGURE 7 ).

Only one polymorphism was found, a small inversion in the base of IIL. The sex chromosomes were undifferentiated (X0 Y 0), although a hint of unpairing was present in the expanded centromere region of chromosome III in males.

Etymology. The species name “ phrygiensis ” is from the ancient kingdom of Phrygia in Western Anatolia, the dominant empire in Asia Minor from about 1200 to 700 BC in what later would become Turkey. The type locality of M. phrygiensis is now known as the Phrygian Valley.

Holotype. Pupa with cocoon and larval head capsule (80% ethanol) ( USNM). Type locality ( Fig. 8 View FIGURE 8 ): TURKEY, Kütahya Province, Ağaçköy (village), Çandiraz stream (local name), 39º21’14.8”N 30º06’29.4”E, 954 m above sea level (asl), 11 April 2007, collected by Ü. D. Şirin.

Paratypes. Same data as for holotype: 16 April 2000: 10 pupae and 7 larvae (80% ethanol) ( CUAC), 18 pupae and 12 larvae (80% ethanol) ( EOUC); 11 April 2007: 3 females and 5 males (pinned), plus 1 male, 1 female, 8 pupae, and 10 larvae (80% ethanol) ( USNM, CUAC), photographic negatives of IL and IIIL ( CUAC), 2 males, 1 female, 11 pupae, and 7 larvae (80% ethanol) ( EOUC); 23 April 2008: 5 larvae (collected in Carnoy’s, transferred to 80% ethanol) ( CUAC); 21 April 2011: 1 male, 1 female, 11 pupae, and 13 larvae (80% ethanol) ( EOUC); 27 April 2011: 5 males, 2 females, 13 pupae, and 9 larvae (80% ethanol) ( EOUC); 10 April 2013: 1 male, 4 pupae, and 16 larvae (80% ethanol) ( EOUC). Turkey, Kütahya Province, Çayca village, Çayca stream, 39º25’18.4”N 30º08’28.7”E, 974 m asl, 27 April 2011, Ü. D. Şirin: 18 pupae and 24 larvae (80% ethanol) ( EOUC), 6 pupae, 4 empty cocoons, and 6 larvae (80% ethanol) ( CUAC), 2 pupae, 6 mature larvae (collected in Carnoy’s, transferred to 80% ethanol) ( CUAC). Turkey, Kütahya Province, Incik village, Incik stream, 39º32’08.8”N 30º15’07.6”E, 1011 m asl, 27 April 2011, Ü. D. Şirin: 4 pupae (80% ethanol) ( CUAC); 19 April 2014: 4 pupae and 7 larvae (80% ethanol) ( EOUC).

Bionomics. Metacnephia phrygiensis was found in three streams at elevations of 954–1011 m asl. Çandiraz stream at the type locality flows through agricultural land and is about 1.5 m wide and 20–25 cm deep, with a gravel and clay bed ( Fig. 8 View FIGURE 8 ). The water temperature on 11 April 2007 was 21 ºC. Flow typically persisted throughout the year, although water levels decreased in the last months of summer and in particularly dry years, such as the summers of 2005 and 2006, flow might have ceased altogether. Çayca stream, about 10 km from the type locality, was similar to Çandiraz stream, whereas Incik stream, about 30 km from the type locality, was larger and had a sandy bed. All three collection sites were in the Anatolian Conifer and Deciduous Mixed Forests Ecoregion, the same ecoregion inhabited by our previously described species, Prosimulium anatoliense (Adler & Şirin 2015) .

The selective value of the fenestrated cocoon of M. phyrgiensis is not known. Openings in the cocoon walls of some black flies produce microflow patterns that aerate the pupal gills, although direct exposure to suspended particles could abrade the gills ( Eymann 1991), which would be of particular concern for species with fine, multifilamented gills. The cloudy water or sandy substrates of the streams where M. phrygiensis was collected suggest that the fenestrated cocoon would leave the gill vulnerable to abrasion. Experimental tests of flow patterns and particulate loads of streams in the habitats of M. phrygiensis are needed.

A single generation is produced annually. At the type locality, the species was first found (larvae and pupae) in April 2000. No specimens could be found in April of the following 5 years, but in April of 2007, the species appeared again. Larvae and pupae at the type locality were collected primarily from trailing vegetation, but at the other two streams, they were collected from stones and trailing vegetation. Associated species at the type locality included the Simulium ornatum complex, S. pseudequinum Séguy , and S. balcanicum (Enderlein) .

Females and males were collected with an aerial net on 11 April 2007 while they were flying beside Çandiraz stream. Females are presumably ornithophilic, based on their well-developed bifid claws.

Comparisons with related species. Compared with species sufficiently illustrated in the literature (cf. Adler et al. 2004), the hypogynial valves, anal lobes, and genital fork of M. phrygiensis are typical of the genus. The spermatheca resembles that of species with an unpigmented area at the junction of the spermathecal duct.

The male resembles many of the species of Metacnephia , perhaps in part because the genitalic details, often subtle, are not captured in most illustrations. The presence of a dorsal plate in M. phrygiensis , which previously had not been illustrated or mentioned in descriptions of species in the genus, might not be unique. Rather, the apparent novelty might be an artifact, having been overlooked in other species.

The pupa and cocoon are among the most structurally distinct in the genus. The fenestrated cocoon of M. phrygiensis is unique among known species of the genus. The elongated, low profile of the cocoon resembles the unfenestrated cocoon of M. amphora (cf. fig. 19D of Bass 1998). The pupal gill also is unique in bearing a pair of filaments, each single or bifurcated in the middle group, which are thicker than all other filaments in the gill (arrow in Fig. 3 View FIGURE 3 D).

The larva of M. phrygiensis resembles that of M. amphora and M. nuragica Rivosecchi, Raastad & Contini (cf. fig. 42.6 of Rivosecchi 1978), based on the amphora-like shape (i.e., markedly narrowed anterior extension) of the postgenal cleft. It can be distinguished from these species and all others by the unique configuration of the filaments in the gill histoblast.

Of the chromosomally known species of Metacnephia , M. amphora is most similar to M. phrygiensis , sharing IIS-2 and IIL-6, which are widely shared among most investigated members of the genus, and IIIL-6, which, though fixed in M. phrygiensis , is an autosomal polymorphism in M. amphora .