University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln

Center for Systematic Entomology, Gainesville, Insecta Mundi Florida

March 1985

Four undescribed Oligocene craneflies from Florissant, Colorado, (Diptera:Tipulidae)

F. Martin Brown University of Colorado Museum, Boulder, CO

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Brown, F. Martin, "Four undescribed Oligocene craneflies from Florissant, Colorado, (Diptera:Tipulidae)" (1985). Insecta Mundi. 506. https://digitalcommons.unl.edu/insectamundi/506

This Article is brought to you for free and open access by the Center for Systematic Entomology, Gainesville, Florida at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Insecta Mundi by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 98 INSECTA MUNDI Vol. 1, no. 2, March 1985

Four undescribed Oligocene craneflies from F.lorissant, Colorado, (DipteragTipulidae)

F. Martin Brown Research Associate, University of Colorado Museum Boulder, CO.

The following described craneflies were condition. Eyes prominent, about 0.8 in discovered during ongoing research at the diameter, rostrum protruding, palpi not Museum of the University of Colorado in well defined, antennae fragmental, one 1.4 preparation of parts of the Colorado Natural with only 8 segments exposed. Thorax History Inventory. prominently convex in profile 2.7 long, 1.8 These Oligocene shale specimens are deep. .Legs in poor condition. Part of one somewhat difficult to study. This is espec- T3 leg in place: femur 6.6 long, tibia 5.9 ially true of with lightly sclero- long and tarsus represented by a short tized veins. With proper illumination and a fragment. Abdomen 6.5 long and good binocular microscope, the veins often clearly male. Abdominal markings these: on appear as glittering lines on the shale. The each segment posterior edge broadly dark veins often are better seen when the specimen brown with short, broad, long extension form- is placed so the veins are illuminated from ing a broken lateral band; in lateral aspect one end. Sometimes the shale is so rough a strong suggestion of. a broad, dark that this lighting does not improve their mediodorsal stripe. visibility Cell R 1.0 long and 0.3 deep: Rs only 0.45 long. btigma subtriangular wlth broad The help of Dr. George W. Byers of Uni- base on costa and filling apical two-thirds versity of Kansas was immeasurable during of cell R . Sc2 0.2; R 0.4, R 1.8, R4+5 the preparation of this manuscript. He not 2.7. ~edtanbranches, h:21.55, d 1.60, M only verified, or suggested, generic assign- partly covered thus immeasurable, h4 1.5 ani ment but also prepared the illustrations of Ms 4.9. Cubital vein bends toward the poster- venation. Mrs. Grace H. Kemper, as usual, ior margin more and more as wing margin is helped with measurements and processing of approached; Cu and the cubital fold very the manuscript. close and Cu much the stronger; from m-cu to margin 1.2 and from m-cu to basal end of vein 6.0. Tip of 1A 0.9 basad of 'tip of Cu on margin; at margin 2A about 2.6 from 1A; 2A not much more than one-third length of Tipula (nicrapsis) decorata, (Fig. 1) wing (3.4 vs 9.5). Discal cell 0.4 x 0.23; on one wing nearly triangular. Length of The holotype had originally been deter- cell Ml more than half the distance from the mined as Micrapaia paludis Scudder, very bifurcation Ms to the margin in the apex (1.5 similar in important details, by an unknown vs 2.8). In one wing a short stub extends student of fossils in the University Mus- agicad from the discal cell (see drawing). eum. I accepted this.determination until I set upon verification of all of the deter- mined preparatory to a report on Holotype: UCM 29988 and its reverse (30067). them for the Inventory. The specimen is Collected by Wilmette P. Cockerell, probably somewhat better preserved than is Scudder's in 1908, station 14, Florissant Lake Bed type of paludis. Shales, Oligocene. The considerable natural coloration of Two features immediately set decorata the wing that must have occurred in life apart from paludis: the discal cell of the gave rise to the specific name, decorata. latter is qu:drilateral, almost rectangular, The placement of decorata in Hicrapsis probably an atypical* anomaly; in decorata Scudder ignores the quadrate discal cell of it is crudely hexagonal. Only the stigma of the type species of the genus, paludis paludis is colored; in decorata there is Scudder. Otherwise, the specin:en is quite in considerable coloration on the wing, and the keeping with Micrapsis. A quadrate discal stigma is very much darker than the rest of cell occurs among Tipula now and then as an the pattern. The pattern in decorata consists abnormality. The greatest difference from of rather broad marginings of the veins Tipula is the short Rs; which is throughout the wing except the basal part of characteristic of Scudder's Tipulidea. R; a rather large patch from cell R to the This genus too fits into the genus small discal cell; several diffuse pa&ches in Tipula in its current interpretations. In the apical area; no light patches like those fact, Scudder (1894:238) seemed a bit in Tipula carpenteri Alexander appear to be reluctant to erect the new genus, except for present. the short praefurca (Rs). The apparent The following details describe decorata. absence of Sc in Micrapsis probably is an All measurements are in millimeters. illusion. It nay well be hidden beneath the Body length 10; wing length 9.5, wing radius. depth 2.3, wing ratio 4.13. Head in fair Vol. 1, no. 2, March 1985 INSECTA MUNDI

Tipulidae: Limoniinae lighter is a broad margining patch on m-cu; another vaguely on Ms about its midpoint. Limonia (Dicranomyia) rohwer i, n. sp. (Fig. There may be narrow marginings on most 2.) veins. The fossil is a male in fair condition. The veins are best seen with flat All measurnents in millimeters. illunination (fiber-optic ring light) and Body length: 7.4 , incomplete, probably was magnification of 30-40 Ciianieters. Only the about 8.5 at most. Head appendages not stigma is colored. All aimensions are in clear. Thorax moderately convex; abdomen niillineters. represented by six segments, apex lost, sex Body: 5.5 long, segnentation and unknown. Legs appear short for a tipulid and genitalia visible; thorax moderately convex; in too poor condition to be neasured or head small, more or less globular, mouth described. parts not well preserved, only two or thrce Wing: 7.7 long and 2.5 wide, about 3.1 basal seonents of one antenna remaining. times as long as wide. Anterior apical area Legs slender and long, no pronounced illcrease difficult to interpret. Sc stands free of R. in diameter at any joints, each successive Cross vein between then, not found. Sc segment of less diameter: Leg T femur 4.7 terminates in margin above where R3 springs lcng, tibia 4.6 long, tarsus 5% long but from R,. R1 0.4 long, R2 about 0.8, R claws invisible: Leg T3, femur 5.3 long, 2.1; np+? 2.65 long and the strongest brand tibia 6.6 lonq, tarsus 3.5 lonq, but of radluJ In this specimen. Fiedian branches: Wing: 5.0 long, 1.25 wide, length M1+ 1.9; K1 from fork to margin four times the width. Stubby cross vein each2 1.2; K3 y:r:than 1.9 with marginal (Scl ?) connects Sc with R near origin of tip buried in stone; even more of M4 R~. Sc continues to costal margin above buried, the visible bit about 1.0 long; m- mlddle of cell RJ. There are three radial cu 0.45 long but marginal width of fifth and three medlan branches. Cu has a posterior cell (M4) cannot be neasured. Cu pronounced turn toward the hind margin at m- about 5.3 long with outermost 0.9 cu. Cubital fold ends just beyond m-CU. detlected toward hind margin. Cubital fold Anal veins undecipherable. seen in traces close to Cu as far as m-cu. Vein measurements are these: R1+ 0.12 1A meets margin 0.3 (?) basad of tip of Cu; long; R3 4, 0.9 long; Rg, 1.2 long; %; plus 2A reaches margin 2.7 farther basad, very Mlt2, 1.b long. Marginal parts of rest of gently curved. velns obscured. estimated 1.0 long Cell R1 2.1 long with Rs (Scudder's and M 1.2 lonC2 Cu extends about 0.5 praefurca) 1.5 long. Origin of R beyondt$-cu: R~ (Scudder's praefurca) 0.6 perpendicularly 0.9 from Cu. Greatest deptR long. of cell R1 is 0.4. Discal cell difficult to Measurements related to cells are see but appears to measure 0.9 long and 0.4 these; cell R1 1.12 long and 0.3 deep; wide. Thus stalk of second posterior cell discal cell 0.6 long and 0.25 deep; cell ( ) about 1.0 long. M3+4 (nominally fifth posterior) about twice ~oiotype: UCN 4920, collected by T. D. A. as wide at margin as m-cu is long (0.7 vs Cockerel1 at Florissant, Teller County, 0.32.) Colorado, in the Oligocene Lake Bed Shales. Holotype; a male, UCM 30017 collected by Cockerell's precise station for this fossil George N. Rohwer at Cockerel1 (U of Colo) pit is not known. 17 probably in 1908. The species is named Named for Theodore Dru Allison for him. Cockerell, second only to Samuel Hubbard Scudder as an explorer of the insect fossils Dicranota cockerelli, n.sp. (Fig. 4.) of Florissant. Byers' comment (in m):"I am inclined to think this specimen is a Dicranota, Gnophomyia (Idiognophomyia?) seiverti, n.sp. something near D. flaveola (Osten-Sacken) (Fig. 3) ...Too bad we can't check details such as If this insect were flying today, its little hairs on the eyes. I actually tried capture would cause no consternation. It is this." Thus Dicranota is used with reserva- so- like niodern species of Gnophomyia that tion. The venation is not all that it could thcre appears no question about the antiqcity be , but what is preserved does not deny the of that genus. The apparent absence of generic placement. In fact, it is better cross-veins between Sc and R above cell R preserved than it at first appears to be. the general shape of tte wing and of t?: The specimen is obviously unlike anything discal cell, ar.,cng other features, sugcjests that has been named from Florissant. What the subgeneric assignment made above. appear to be only three visible veins in the Probably a female, with wings in fairly wing resolve into almost a full complement good condition. :.Iost of the head appendages when viewed at 40x magnification with ring are missing and only one leg is con~lete lighting. Most of the veins appear to be enough to neasure. Wings slightly over lap- colorless but glisten. ping and the apical margins still narrowly In addition to the stigma there are covered by shale. It would be too risky to several patches on the wing as intense in try to scale this off. color as the stigma. These are: a large one In addition to the moderately large on origin of R4+5 extending broadly along stigma, there are narrow marginings along the cross vein r-m to base of the discal most of the veins in the radial and medial cell; a small one on origin of R,. Much fields. There a:-;Jears to ue a rather large 100 INSECTA MUNDI Vol. 1, no. 2, March 1985

apical dusky patch that follows the contour of the apex co Ii4. The full extent of this patch is hidden by shale that covers the ape;: of one win9 cocpletely and nar~inallyon the other. There may be some diffuse patches in the niddle and basal parts of the wing, but these are very vague and may not really exist, All measurments in millimeters. Body: 6.7 long in a straight line, probably around 7 if straightened. Head small and globular; eyes very large, possibly holoptic; nouth parts confused; antennae absent beyond basal three or four segments, 6.4 remaining. Thorax somewhat crushed, probably not strong- ly convex. Abdomen rather stout but only last f,our segments including genitalia visible. Only leg T on left side measurable, a fragment of ano$her fenur present. T3 feeur 4.9; tibia 4.4 est.; three tarsomeres clear, measuring 1.85, 0.9 and 0.4 from tibia outward; only 0.3 of fourth segment partly visible, claws invisible. Wing; about 7 long, extreme apical margin concealed, width 2.35, about 3 times as long as wide. Venation very much like that figured by Alexander in Curran (1934), Tipulidae P1. IV, f. 43, differing only in minor features. Sc joins C at level of middle cell R1. A tiny cross-vein (Sc2?) ties Sc to R1 about 1.75 beyond origin of R,. Radial branches measure: R1+2 1.1; R3 2.3; R4 2.8; R~ 2.9 (all measurements approximate because of attempt to estimate position of wing margin.) Median branches measure: 2.9; M 1.6; M4, 1.7 ; and the median :i!:fi 3.2. 2; measures approximately 3.4 from base to m- cu, and 1.15 from there to wing margin. 1A appears to meet wing margin 0.6 basad of Cu and 2A 0.8 basad of 1A. Cell R1 2.3 long and 0.3 deep at its deepest. Origin of Rs is 0.7 perpendicular- ly from Cu; Rs (Scudder's praefurca) 2.1 long. Discal cell 0.9 long and 0.4 at its widest. Cross vein m-cu meets discal cell Figurn 1. Holotype, Tlpul. lfiorg.l#) &~rat., n.rp. G~avingby just apicad base of discal cell. George Bysra. UOL No. 2988 Holotype: a female, UCM 30066, collected by Seivert A. Rohwer at Cockerel1 (U of Colo.) station 17, probably in 1908. The fossil is figure 2. Holotype, Li.Dnia (Mcnnolpria) mhd, n.rp. B-oting by named for him. The greatest differences seen between Bmm. UOl No. 30017 the venation of Gnophomyia tristissima, the type of the genus, and seiverti are the I3 ye3. Holotype, (hopholyi. (Idiognophollyla ? ) aieverti, n.sp. terminations of the two anal veins being mwing by *orgo -I-, uw 30066. closer than usual, the somewhat straighter branches of the radial vein, and a more slender cell R1. klgure h. Holotype, acnnot. ( r.:.), cockerelli, n.8p. &Nbg by George By.n. UQI lr920.