Leptohyphes ferruginus Allen and Brusca

Baumgardner, D. E. & Mccafferty, W. P., 2010, Revision of the genus Leptohyphes Eaton (Ephemeroptera: Leptohyphidae) in North and Central America, Zootaxa 2360 (1), pp. 1-33 : 13-15

Leptohyphes ferruginus Allen and Brusca

Leptohyphes ferruginus Allen and Brusca, 1973:88 ; Allen, 1978; McCafferty and Baumgardner, 2000 (syn of L. zalope ) Leptohyphes piraticus Allen, 1978:554 ; Baumgardner and McCafferty, 2000 (syn of L. zalope ) new synonym

Diagnosis: Mature L. ferruginus larvae are relatively small among species of Leptohyphes in North and Central America. Mature male larvae are 3.0–3.5 mm in length, and female larvae 4.0–4.5 mm in length. Most other species of mature Leptohyphes larvae are at least 5 mm in length. The red body coloration (best seen in freshly preserved material) will readily distinguish this species from others in the genus in North and Central America. Some individuals have limited black maculation at the sublateral margins of the abdominal terga. Other characters include scattered setae on the sublateral margins of the abdominal terga, claws with four to six marginal and one submarginal denticle, and the presence of elongate setae on the dorsal surface of the profemur. The vertex of the head is red and without complex maculation as in L. zalope or L. apache .

The first description of the adult stage is given below on the basis of one reared male and one reared female subimago, one reared female adult, and one reared, partly emerged male adult with most of its subimago cuticle shed. No attempt is made to distinguish the adults from other species of Leptohyphes in the adult stage due to the relatively few adult species known at this time.

Description: Male adult. Length. Body, 3.0 mm; forewing, 4.0 mm; hind wings, 0.75 mm, cercus, 10.0 mm; median caudal filament, 12.0 mm. General coloration reddish-grey with black and grey shading. Head: gray with extensive black shading between lateral ocelli and on vertex; lateral and median ocelli black at base, clear in distal one-third; antenna pale. Thorax: prothorax gray with extensive overshadings of black dorsally and laterally; meso- and metanotum yellowish brown with diffuse overshadings of black shading mostly on pleuron. Legs: prolegs not shed from subimago skin; mid- and hind legs grey with black maculation on mid dorsal surface of femora. Forewings (female adult) ( Fig. 26 ): translucent; costa, subcosta, and R 1 reddish brown for most of their length; vein CuP strongly curved towards A; vein ICu 2 attached to ICu 1 by basal crossvein; ICu 1 attached to CuA by crossveins; MP 2 united basally to veins CuA and IMP by cross veins. Hind wings: present on male, with an elongated costal process and two longitudinal veins. Abdomen: gray with diffuse black shading dorsally and along lateral margins; sterna pale with black stippling limited to margins. Genitalia: forceps three-segmented, penes with basal half fused, distal parts divergent, “Y” shaped; cerci and median caudal filament present, well developed. Female subimago. Body length 4.0 mm. Forewing length 5.0 mm. Hind wing absent. Cerci and median caudal filament missing. Head colored generally as in male; compound eyes small, widely separated; diameter of one eye less than distance between eyes. Thorax colored as in male. Forewings as in male; hind wings absent. Abdomen generally as in male, except yellowish-brown with extensive black shading on terga. Larva: Length: Body 3.0–4.5 mm; caudal filaments 3.5–4.5 mm. General color dark red to reddish-brown with black markings. Head: red, with thin black line on frons between compound eyes and at base of antennae ( Fig. 27 ), or restricted to vertex between lateral ocelli ( Fig. 28 ); medioposterior margin of head with inverted “U” markings ( Figs. 27, 28 ); some individuals with thin, black lines running from compound eyes posteriorly ( Fig. 27 ). Thorax: dark red; pronotum with black sublateral maculae ( Fig. 27 ); without anterolateral projections and median tubercle. Legs. Proleg ( Fig. 29 ): femur with transverse row of elongate setae along dorsal surface; anterior margin with few, scattered filiform and elongate setae distally; tibia with setae absent along outer margin; inner margin with regularly spaced filiform setae; tarsi with filiform setae along inner and out margin. Meso- and metalegs ( Fig. 30 ): femora with robust and stout setae medially on dorsal surface; anterior margin with robust setae; posterior margin with elongate setae medially and distally; tibiae with numerous elongate setae present along most of anterior and posterior margins; tarsus with few, scattered filiform setae along anterior and posterior margins; claw ( Fig. 31 ) with four to seven marginal and one submarginal denticle. Abdomen: red with pale margins; sublateral margins of tergites seven and eight with scattered, sparse setae ( Fig. 32 ); operculate gill pale reddish-brown, margins pale; gill formula 2/5/5/5/2.

Distribution: Leptohyphes ferruginus is known from the southwestern United States (Arizona and New Mexico), Mexico ( Allen, 1978), Guatemala ( McCafferty et al., 2004), Honduras ( Allen, 1978), and is newly documented in Costa Rica. Although apparently widely distributed in Central America, the species does not appear to be common.

Discussion: Leptohyphes ferruginus was described by Allen and Brusca (1973) based on three larvae from a single location in Vera Cruz, Mexico. Leptohyphes ferruginus was distinguished from all other known species of Leptohyphes on the basis of red body color, shape of the denticles on the tarsal claws, and arrangement and number of spines on the femora. Leptohyphes piraticus was described by Allen (1978) based on a single larval specimen from Honduras, and distinguished it from other Leptohyphes on the basis of red body coloration and a transverse band between the compound eyes. Baumgardner and McCafferty (2000) synonymized L. ferruginus and L. piraticus under L. zalope , because of the general similarity of the larvae of the two species, a lack of any additional specimens that appeared to match the concept of L. ferruginus , and the lack of red coloration on the larvae of the type series. Recent examinations, however, of mature larvae from several locations in Guatemala, Costa Rica, and Arizona readily match the description of L. ferruginus given by Allen and Brusca (1973) in terms of the red body coloration, size of the larvae, and features of the claws, femoral spines, and arrangement of setae on the abdominal terga. In addition, many larvae possess a thick, black band between the compound eyes, as was described for L. piraticus , although this does appear to be somewhat variable among individual specimens. Although coloration is often highly variable in species of Leptohyphes larvae, this particular species appears to have little to no variation of the body coloration. Because of this new material which maintains the concept of L. ferruginus , the species is revalidated.

The only distinguishing feature separating L. ferruginus from L. piraticus is the reported presence of a thick, transverse black band between the compound eyes of L. piraticus . Otherwise, the two species are identical in terms of their unique red body coloration. However, as discussed above, this band is also infrequently found in some individuals of L. ferruginus . In addition, the presence of a transverse band between the compound eyes is not uncommon to many species of Leptohyphes . Also, it is not unusual to find individuals of the same species at the same location to vary in terms of head patterns. Because of this interspecific variation, L. piraticus is considered synonym of L. ferruginus .

The holotype of L. ferruginus is mature and in good condition, but the red color of the body appears to have faded and is not readily apparent. The two paratypes examined from CAS are also faded and in fair condition. The original description of this species listed six paratype larvae, four at CAS and two at the University of Utah. Only two of the four larvae listed as being at CAS could be located. The two specimens from the University of Utah are now evidently in the collection of FAMU. Although these two larvae at FAMU possess a label indicating that they are the paratype larvae of Leptohyphes ferruginus , their associated locality label reads, “Vera Cruz, Mexico, Río Tecolapan, Santiago Toxla on Highway 80, 16-VII-1966, RKA ”, which is an incorrect locality for the paratypes. Either these two specimens are not the two associated paratypes or either they have an incorrect locality label, which appears to be the case, because the two larvae appear to readily match the original description of L. ferruginus . The holotype of L. piraticus is a pre- emergent female, in poor condition, partly torn and badly faded. The head has been removed, dissected, and mounted on slide with mouthparts .

Type material examined: Leptohyphes ferruginus HOLOTYPE: MEXICO, Vera Cruz, Rio San Marcos at Apapantilla , 3 miles southeast Villa A Camacho, 12-XI-68, R . K. Allen. [ CAS Type #11974] . PARATYPES, same data as holotype, 2L, 4 slides, [ CAS]. Leptohyphes piraticus Allen , HOLOTYPE, larva, HONDURAS; Dept. Chotuteca , small stream, Choluteca, ca. 16 mi. E. Jicaro-Galan, Pan American Highway, 10-X-64, JS Packer, 3 slides [ FAMU, # E2043 , 1 T] .

Other material examined: COSTA RICA: Heredia: Río Isla Grande at Hwy. 4, ca. 5 Km. W. of Río Frio (N10˚23’31”; W83˚58’04”, elev. 200 ft), 10.vi.2001, 1 L, D.E. Baumgardner [ TAMU] . Puntarenas: Río Jaba at Las Cruses Biological Station, ca. 14 Km. S. San Vito (elev. 4000 ft.), 23-24.vi.2001, 1 reared male subimago with cuticle partly shed and larval cast skin, D.E. Baumgardner [ TAMU] . GUATEMALA, Alta Verapaz: Río Cahabon at Hwy. 7E, San Julian (N15˚19’09”; W90˚19’06”, elev. 4700 ft), 14.vii.2001, 2 reared female subimagos with larval cast skins, D.E. Baumgardner [ TAMU]; Río Stainkreec ,.8 Km E. from jct. of Hwy. 9&10, Rio Hondo (N15˚02’23; W89˚35’14”, elev. 600 ft), 15.vii.2001, 12 L, D.E. Baumgardner [ TAMU] . El Progreso: Quebrada Las Pericas at Hwy. 17, 11.1 Km W. from jct. with Hwy. CA 9 (N14˚54’54”; W90˚05’52”, elev. 1040 ft) , 12.vii.2001, 7L, 1 reared male subimago, D.E. Baumgardner [ TAMU] . Zacapa: Río Cayo at CA Hwy. 9, 2.3 Km E. Santa Cruz (N15˚00’54”; W89˚39’09”, elev. 830 ft), 14.vii.2001, 4 L, D.E. Baumgardner [ TAMU] . HONDURAS: Choluteca: approx. 16 mi. E. Jicaro-Galan on Pan-American Hwy. , small stream, 10.x.1964, JS Packer, 1L [ CAS] . UNITED STATES: Arizona: Gila Co., East Verde River on Road 406, 10 mi. E. Payson , 19.vii.1970, 3L [ CAS] . New Mexico: Grant Co., Gila R . at Hwy. 15, ca. 7 mi. S GilaNat. Monument (N33°10’46”; W108°12’21”; 5580 ft), 18.v.2004, 1 L, D.E. Baumgardner [ TAMU] .

Figures

FIGURE 32. Leptohyphes ferruginus, larva, abdominal tergites 6–10 (dorsal) [scale bar A].

FIGURES 26–31. Characteristics of adults and larvae of Leptohyphes ferruginus. 26, forewing, female adult [A]. 27, head and prothorax (dorsal) [scale bar C]. 28, head (dorsal) [B]. 29, foreleg [E]. 30, hindleg [D]. 31, hind claw (ventrolateral) [F]. Scale bars (mm): A = 1.5; B = 0.025; C, F = 0.05; D, E = 0.5.