Typophyllum morrisi, Braun, Holger, 2015

Braun, Holger, 2015, Little walking leaves from southeast Ecuador: biology and taxonomy of Typophyllum species (Orthoptera, Tettigoniidae, Pterochrozinae), Zootaxa 4012 (1), pp. 1-32 : 6-11

Typophyllum morrisi sp. nov.

( Figs. 5 , 6 , 7 )

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:470144

Braun 2002: 66 ( Typophyllum sp. 3, “Bombuscaro-Spaziergehblättlein“), Braun 2008: 220 ( Typophyllum sp. 3).

Etymology. Dedicated to Glenn K. Morris, the pioneer of bioacoustics of neotropical tettigoniids, who documented for the first time songs of some Typophyllum and Mimetica species.

Examined specimens. Male holotype cbt003s04 (sound recording), Río Bombuscaro valley, 1100 m, 19 June 1999; female paratype cbt003s21, Alto Nangaritza, 1260–1350 m, 6–12 April 2009 both leg. H. Braun and deposited in the Museo de La Plata; 18 additional specimens from three sites are currently in the collection of the author: Bombuscaro 1000–1180 m, 13–19 November 1998: male cbt003s01 (recording) and male cbt003s02 (raised from nymph), 19 June 1999: male cbt003s03 (recording) and male cbt003s04 (recording), 20 July 2002: female cbt003s05 and male nymph cbt003s06 (leg. H. Braun); Maralí 860–980 m, 12 January 2009: female cbt003s07, and male cbt003s09 (leg. H. Braun); Alto Nangaritza 1260–1450 m, 6–17 April 2009: female cbt003s10, female cbt003s11, female cbt003s12, male cbt003s13, male cbt003s 14, male cbt003s15, male cbt003s16, male cbt003s17, female cbt003s18, male cbt003s19 (damaged spider victim), and male cbt003s20 (leg. Elicio Tapia & H. Braun). [male cbt003s08 turned out to be a different species, see below Typophyllum sp.]

Notes. There are 8 males and 2 females in the collection of G.K. Morris (inspected 2004/2005) from the Amazon region of Ecuador in Napo Province. According to morphology they could belong to this species as well, but the male calling song is different. Probably they are the same as Typophyllum sp. nr. trapeziforme Morris et al. 1989 , whose song is compared below to the one of T. morrisi . Another male from this area belongs to the collection of the University of Michigan Museum of Zoology, Ann Arbor ( UMMZ): Napo Province, about 8 km south-east of Tena and 2 km south of Ongota, 12 May 1963 leg. T.H. Hubbell & L.E. Peña. This site is at about 500 m and around 300 km north of the type locality of T. morrisi .

Description. As in T. egregium the internal tympanal chamber walls are not expanded beyond the dorsal surface of the fore tibia, but are developed like the external ones. Also, the bases of the hind tibia are not expanded, placing this species like the preceding one into the first group according to Vignon (1925a). Tegmen shapes ( Fig. 5 C) do not correspond sufficiently well to any described males or females. And in males there is a unique modification of the stridulatory area at the base of the left tegmen: the proximal end of the fairly bulky stridulatory vein is dorsally developed as a knob, and directly behind it is a second knob of about the same diameter and as isolated structure being a little bit more conspicuous. The speculum of the right tegmen seems to be fairly stiff and is translucent but not transparent ( Fig. 7 B). In females the tegmina are mostly emarginated in a characteristic fashion at the distal anal margin ( Figs. 6 A, 7D), and only rarely the margin is uniform ( Fig. 7 E). One distinctive trait is shared by both sexes: the hind tibia sports a little below the middle, on the dorsal internal edge, a rounded, often downward-directed and drop-shaped process, of about the same diameter as the tibia ( Fig. 5 B). The prosternum has no spines; mesosterum and metasternum are laterally pointed, but not terminating as distinct spines.

Coloration. Little variation; various shades of brown; most individuals are dark brown ( Fig. 7 ).

Measurementes. Tegmen length in males 13–16 mm and in females 25–28 mm, hind femora in males 12–13.5 mm and in females 18–20 mm, antennae in females at least 50 mm.

Acoustic behaviour. The two males that were recorded produced calls consisting of 3–6 (mostly 4 or 5) pulses ( Fig. 19 C). One individual pulse lasts about 30 ms and they are repeated every 120–130 ms. A five-pulse call lasts 500 ms at 23°C. Mostly two or three calls were produced together, separated by intervals of 400–500 ms. The pulses consist of a sustained and almost pure sine wave. The spectrogram shows a very narrow peak at 20.5 kHz and a faint harmonic at 41 kHz. The males seem to call only sporadically and the unique and easily recognizable song was never heard in the natural habitat while listening with a bat detector at night. The two knobs on the dorsal portion of the left tegmen of males might serve to dampen vibration of this tegmen, which otherwise could cancel out by negative interference the sound radiated by the speculum of the right tegmen, in case both tegmina vibrate out of phase.

For the above-mentioned Typophyllum sp. nr. trapeziforme ( Morris et al. 1989) are described trills of 47–132 pulses with a total duration of 2.5– 7.0 s. The principal carrier frequency is 23.2 kHz. The high duty cycle might be due to captivity (see above T. egregium ; extremely elevated calling activity compared to duty cycles of freshly caught males, and males in natural habitat, also occur in other Ecuadorian katydids—pers. obs.). However, the carrier frequency is slightly higher than described for T. morrisi . So it is currently uncertain whether the lowland population from the Ecuadorian Amazon is truly conspecific.

Mating behaviour. In a cage with three females and one male, was once at night observed the male riding on a female, but this female was found moribund the next day and no copulation occurred.

Distribution. Eastern foothills of eastern Andean cordillera at 850–1450 m in south Ecuador, probably extending down into Amazon region of Ecuador and northern Peru.

Figures

FIGURE 5. Typophyllum morrisi sp. nov.: A. male habitus, left fore femur in lateral view, and head in dorsal view (body length 18 mm including tegmina, slightly obese after longer time in cage feeding on cucumber, after specimens cbt 003 s 03 and – s 04); B. left hind femur with typical medial process (males cbt 003 s 02, - s 04, - s 03); C left tegmen of female (25 mm, cbt 003 s 05), left and right tegmina of two males (13 - 14 mm, cbt 003 s 03, - s 04).

FIGURE 6. Typophyllum morrisi sp. nov.: A. female (cbt 003 s 05): B. female nymph (- s 06).

FIGURE 7. Typophyllum morrisi sp. nov.: A, B. male holotype, lateral and dorsal view (cbt 003 s 04); C. male (cbt 003 s 14); D. female (cbt 003 s 10); E. atypical female with uniform anal margin of tegmina (cbt 003 s 12) (see Fig. 5 C for size difference between tiny male and large female).

FIGURE 19. Oscillograms and linear spectrograms of calling songs of four Typophyllum species: A. T. egregium, complete call (field recording, 9.5 ºC, specimen cbt 002 s 21); B. T. onkiosternum sp. nov., one double pulse of longer sequence (cage, 18 ºC, cbt 004 s 01); C. T. morrisi sp. nov., one pulse and below complete call, here consisting of three pulse groups (cage, 23 ºC, cbt 003 s 01); D. T. erosifolium one pulse and below seven double pulses from continuous calling (cage, 20 ºC, cbt 001 s 01); all recordings made at night.