Barbitistes kaltenbachi Harz, 1965

Felix, Rob, Heller, Klaus-Gerhard, Ode, Baudewijn, Rebrina, Fran & Josip Skejo,, 2020, Island mysteries in the spotlight: Barbitistes kaltenbachi and Rhacocleis buchichii, the only bush-cricket species endemic to Croatia (Orthoptera, Tettigoniidae), ZooKeys 936, pp. 25-60 : 25

publication ID	https://dx.doi.org/10.3897/zookeys.936.51599
publication LSID	lsid:zoobank.org:pub:668E08BD-6383-403F-B29C-F47CA7C50E80
persistent identifier	https://treatment.plazi.org/id/8058B0D5-55A8-51A3-8712-29B0758F22F9
treatment provided by	ZooKeys by Pensoft
scientific name	Barbitistes kaltenbachi Harz, 1965
status

Treatment

Barbitistes kaltenbachi Harz, 1965 Figures 1 View Figure 1 , 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7 , 8 View Figure 8

Barbitistes kaltenbachi Harz, 1965: Harz (1965): 443 (description of the species from Brunner von Wattenwyl’s collection, 12 ♂♂ syntypes, and 16 ♀♀ syntypes, depicted in details, measured, based on males and females from Hvar Is., and a female from Trieste) (see Fig. 2 View Figure 2 );

Barbitistes kaltenbachi Harz, 1965: Harz (1969): 75 (included in the key to species of the genus in Europe, depicted in details in figs 224, 237, 242-243, described and measured, cited from Hvar Is., and mentioned from a few mainland localities: Lukovo, Rijeka, Trieste);

Barbitistes kaltenbachi Harz, 1965: Galvagni and Fontana (1993): 204 (comparison with newly described B. vicetinus );

Barbitistes kaltenbachi Harz, 1965: Heller et al. (1998): 25 (listed in the checklist of European Orthoptera );

Barbitistes kaltenbachi Harz, 1965: Massa et al. (2012): 521 (presence in Italy, in the region of Trieste, unlikely);

Barbitistes kaltenbachi Harz, 1965: Warchałowska-Śliwa et al. (2013): 668-669, 671 (reported from Hvar Is., Bogomolje, number and shape of chromosomes determined, as well as sex determination system X0);

Barbitistes kaltenbachi Harz, 1965: Rebrina (2014): 4, 10-11, 14-16, 19, map Karta 1, Photo 1 (distribution in Croatia, Hvar cited as the only confirmed locality, new data from Bogomolje and Sućuraj, E corner of the island of Hvar, presence in Lukovo and Rijeka unlikely, Heller’s findings are the first since the description);

Barbitistes kaltenbachi Harz, 1965: Hollier and Bruckner (2015): 192 (Reported that type series should consist of 12 ♂♂ syntypes and 16 ♀♀ syntypes labelled 'Insel Lesina’ and no specimens are deposited in Natural History Museum in Geneva. Since Harz did not designate a holotype all of the specimens in type series should be considered syntypes. Orthoptera collection in Vienna harbours 31 specimens identifiable as possible syntypes, of which one has been labelled as the holotype, one as allotype, and 16 as paratypes);

Barbitistes kaltenbachi : Chobanov et al. (2016) (assessed as Near Threatened in IUCN Red List);

Barbitistes kaltenbachi : Hochkirch et al. (2016b): 67 (listed among Near Threatened Orthoptera of Europe);

Barbitistes kaltenbachi Harz, 1965: Skejo et al. (2018): 19, 21 (endemic to Croatia, distribution in the country presented, as well as Rob Felix’s photograph from Hum, Vis Is.).

Type material.

Type specimens of B. kaltenbachi are deposited in NMW, Vienna. Harz’s (1965) description is based on 31 syntypes: 12 males (10 from Lesina (Italian for Hvar), 2 from an unknown locality, probably “Dalmatia”), 16 females (12 from Hvar, 1 from Trieste (Italy), 3 with unknown locality) and 3 nymphs from Lesina. A male syntype is erroneously labelled as holotype (Fig. 3 View Figure 3 ).

Material examined.

Croatia • 2♂, 1♀; Vis Is., Mount Hum, Crikvica Sv. Duha; alt. 545 m a.s.l.; 43°02.13'N, 16°06.92'E; 21 Jul. 2011; R. Felix leg.; RFPC • 4♂, 2♀; Hvar Is., near Bogomolje, Likova Glava; 30 May 2006; M. & K.-G. Heller leg.; KGHC CH6738, CH6739, CH6740, CH6751, CH6752, CH6754 • 1♂; same data as for preceding; NBC CH6735 • 3♂, 1♀; Hvar Is., Sucuraj; 30 May 2006; M. & K.-G. Heller leg.; KGHC CH6736, CH6737, CH6755, CH6759.

New record on Vis Island.

Hvar Saw Bush-cricket was found on 20 and 21 July 2011, near the Chapel of St. Spirit (Crikvica Sv. Duha) at Mount Hum, in the southwestern corner of Vis (43°02.13'N, 16°06.92'E, 545 m a.s.l.) (Figs 1 View Figure 1 , 3 View Figure 3 , 4A View Figure 4 ). Hum is the highest mountain on the island, with a peak reaching 587 m a.s.l. The observed specimens represent the first record of B. kaltenbachi on the Island of Vis, and outside of Hvar Is. Four individuals were observed, of which three were collected (see Material examined). Individuals were observed basking in the morning sun on outer leaves of Holm Oak ( Quercus ilex ), at a height of ca. 1.5 meters. Barbitistes was accompanied by Long-tailed Speckled Bush-cricket, Leptophyes laticauda (Frivaldszky, 1868) and Schmidt’s Marbled Bush-cricket, Eupholidoptera schmidti (Fieber, 1861) in the same habitat. The collecting site was inspected for only an hour, and a more comprehensive survey would probably have yielded more sightings.

Additional information on morphology.

The right tegmen of the female has several rows of stridulatory pegs, in resting position covered by the upper left tegmen. To produce sound, the pegs are probably contacted by the slightly enhanced inner edge or a sclerotised vein on the lower side of the left tegmen.

Distribution.

Harz (1965) originally described B. kaltenbachi from Hvar Is., Trieste (mainland Italy), and an unspecified locality (see Type material). Later, Harz mentions the species from Rijeka and Lukovo in mainland Croatia ( Harz 1969). Massa et al. (2012) point out that the occurrence of B. kaltenbachi in mainland Italy (Trieste) is based solely on a female specimen. Since female specimens of Barbitistes are very hard to identify to species level, because of a high degree of overlap in interspecific characteristics ( Nadig 1987), the record from Trieste is considered unreliable. Furthermore, Harz’s records from mainland Croatia are assumed to be based on females and are therefore regarded as doubtful. Therefore, we consider B. kaltenbachi as being absent from mainland Croatia and endemic to the Dalmatian Islands.

All known records of B. kaltenbachi are shown on the map in Fig. 1 View Figure 1 and presented in Table 1 View Table 1 . The first records of B. kaltenbachi after its description by Harz (1965, 1969) were the ones by KGH in 2006, on Likova Glava, near Bogomolje, and near Sućuraj, both on Hvar Is. (Fig. 1 View Figure 1 , 4B View Figure 4 ). In Warchałowska-Śliwa et al. (2013) and Rebrina (2014) coordinates are provided but after mapping, those appear to be incorrect, and are therefore omitted from Table 1 View Table 1 . The distribution on both Hvar Is. and Vis Is. is probably much wider and the presence of the species on nearby islands such as Brač Is., Korčula Is., as well as neighbouring islets, is also possible.

Habitat.

No published data on the habitat of B. kaltenbachi are available. On Vis Is. the species has been found on bushes and small trees of Holm Oak, in maquis intercepted with scattered patches of grassy vegetation and bare limestone rock (Fig. 4A View Figure 4 ). The habitat on Hvar Is. is similar to that on Vis Is. but lacks rocky outcrops (Fig. 4B View Figure 4 ). Barbitistes is an arbusticolous genus, as its members are usually living in bushes, shrubs and on low trees ( Galvagni and Fontana 1993; Pavićević et al. 2014). Thus, Hvar Saw Bush-cricket inhabits typical Barbitistes -habitat.

Song description.

The male calling song consists of short (up to ca. 10 ms), pulse-like syllables without clearly recognisable impulses (tooth impacts). Syllables are arranged in a stereotyped pattern. One loud syllable, the trigger syllable, assumed to be the marker for female response ( Stumpner and Meyer 2001), is followed by a group of two or three (rarely one or four) ‘softer’ syllables (echeme) (Fig. 5A View Figure 5 ). The trigger syllables are 6 to 16 dB louder than syllables within the echeme (Suppl. material 3: Table S3.1). After a short interval, the same pattern (verse) is repeated again and again (Fig. 5B View Figure 5 ). Periods range from 280-400 ms for the verse (verse repetition rate ca. 3 Hz), 120-160 ms for the post- and pre-trigger periods, to 40-50 ms for the syllables in the echeme (Suppl. material 3: Table S3.2). These sequences of verses are variable in duration but may last more than 30 s (Suppl. material 3: Table S3.3), at least while two males are in acoustic contact. During interactions males seem to prefer singing during the other male’s song pauses, but they are not inhibited. Songs overlap quite often, even for many seconds. In situations of overlap, males typically synchronise the pattern: they produce trigger syllables nearly at the same time (Fig. 5B, C View Figure 5 ). The delay between the trigger syllables of two synchronising males is typically below 20 ms (Fig. 5E View Figure 5 ) and the roles of leader and follower change often. After disturbances males are able to reach synchronicity within a few periods. Quite rarely, males add extra syllables (sensu Stumpner and Meyer 2001), ca. 50 ms after the trigger syllable (Fig. 5D View Figure 5 ). These song structures are known from several other Barbitistes -species and are interpreted as female response mimicking ( Stumpner and Meyer 2001).

Species diagnosis.

Males of Barbitistes kaltenbachi can be distinguished from its Croatian congeners, B. ocskayi Charpentier in Ocskay et al., 1850, B. serricauda (Fabricius, 1794), and B. yersini Brunner von Wattenwyl, 1878 (Fig. 6 View Figure 6 ), by the shape of the cerci (Fig. 7A View Figure 7 ). Male cerci in B. kaltenbachi are thickened in their mid-part. The proximal half of a cercus is in an abrupt but obtuse angle with the distal half, giving the cercus an angular sinuosity, like that of an open elbow. Barbitistes constrictus has nearly identically shaped cerci (Fig. 7B View Figure 7 ). All the other species of the genus have cerci of a different shape, in the absence of a thickened mid-part and in being more gradually curved, showing a smoother sinuosity in the apical part (Figs 7C-H View Figure 7 ), except for B. vicetinus , which has uniquely shaped cerci (Fig. 7F View Figure 7 ).

The song of B. kaltenbachi differs distinctly from the songs of all other Barbitistes -species in the temporal pattern of the syllables (Fig. 8 View Figure 8 ). Definite diagnostic differences between females cannot be given. Females of different species of Barbitistes show many similarities, some exhibiting intermediate characters (see e.g., Nadig 1987). In this paper, the photos of females are of specimens present together with males in the same bush and hence are identified as belonging to B. kaltenbachi . See Suppl. material 1: Table S1 for measurements of specimens in collections and literature data.