Ectemnia cerberus, (ENDERLEIN, 1921)

ECTEMNIA CERBERUS ( ENDERLEIN, 1921) View in CoL

Female holotype ( Figs 1G View Figure 1 , 4 View Figure 4 ) in good condition, embedded in a rectangular piece of amber measuring 2.0-cm long × 1.5-cm wide.

Description: This species was originally described by Enderlein (1921) and later redescribed by Crosskey (1994). This latter account, in combination with higher quality images of the holotype than were previously available, is of sufficient detail and quality to make comparisons with all other amber inclusions in this study.

Comments: First described as N. cerberus by Enderlein (1921), this species was later reassigned to Simulium s.l. Latreille by Smart (1945) and thence to Ectemnia by Crosskey (1994). Crosskey (1994) provided 12 character states in support of the placement of cerberus in Ectemnia , including (1) large body size; (2) head with exceptionally narrow frons, bulbous clypeus and short proboscis; (3) unusually broad and flattened paratergites; (4) anepisternal membranes bare; (5) wing with intermixed hair- and spine-like macrotrichia on costa; (6) Rs unforked; (7) R 1 with hair-like macrotrichia only; (8) Sc with setae ventrally; (9) ventral pads of tarsomere 4 extremely large; (10) female tarsal claw with markedly elongate subbasal tooth; (11) hind basitarsus with small but definite calcipala; and (12) abdomen with well-developed seventh sternite. Special comment is warranted about the size of Ectemnia , which Crosskey (1994) considers to include the world’s largest simuliid. In fact, that distinction belongs to Gigantodax bolivianus Enderlein , whose wing length ranges from 7.0 to 7.4 mm ( Wygodzinsky & Coscarón, 1989) – considerably longer than that of the cerberus holotype (c. 4.5 mm) and other large-sized extant simuliids, such as members of Simulium subgenus Trichodagmia (4.6 mm or less) and Ectemnia (c. 4.0 mm or less) ( Fig. 5 View Figure 5 ). Therefore, large size alone cannot be considered a reliable indicator of taxonomic affinity. The other characters cited by Crosskey are equally problematical in that they are variously shared with members of other simuliid genera. Adler et al. (2004) gave ten character states in support of the monophyly of extant Ectemnia , of which only two are present in adults: (1) cibarium of female with one to 11 setae on anteroventral margin and (2) ventral plate of male at least 2.5 times wider than long in ventral view. Unfortunately, evaluation of these character states requires dissection and cannot be evaluated in fossils.

Material examined: Two images of the E. cerberus holotype courtesy of Dr Christian Neumann, Museum für Naturkunde der Humboldt Universität, Berlin, Germany .

ECTEMNIA LITHUANICA YANKOVSKY & BERNOTIENE, 2005 View in CoL

Female holotype ( Figs 1H View Figure 1 , 6 View Figure 6 ) in good condition, embedded in a subtriangular piece of amber measuring 1.6- cm long × 0.85-cm wide.

absence of a pedisulcus) is a plesiomorphic character state shared by the great majority of simuliid genera ( Adler et al., 2004). Accordingly, this character state cannot be considered diagnostic of Ectemnia or any other genus. Finally, the wide frons and apparent absence of a calcipala excludes lithuanica from Ectemnia , as currently defined. In summary, there is no evidence of a close relationship between lithuanica and the giant black flies considered in this study. Not yet having the opportunity to study the actual holotype of lithuanica , we prefer not to speculate on its generic assignment nor its status relative to other nominal species of Baltic or Rovno amber simuliid. Therefore, we here consider lithuanica to be an incertae sedis member of the tribe Simuliini , pending further study.

Material examined: Three images of the E. lithuanica holotype courtesy of Dr Sergey Aibulatov , Zoological Institute, Russian Academy of Sciences, St Petersburg, Russia .

Description: Examination of new, higher quality images of the E. lithuanica holotype reveals that Yankovsky & Bernotiene (2005) considerably overestimated certain aspects of body size. For example, their estimated wing length of 8.0 mm was clearly based on an optical illusion created by a bubble or crack in the amber when the inclusion is oriented in lateral view (cf. their figs 1B, 2). In contrast, the dorsal view reveals that the wing length of lithuanica is well within the normal size range for simuliids, with a maximum length of just 2.5 mm ( Fig. 6B View Figure 6 ). Similarly, our estimate for overall body length (c. 3.3 mm) based on new images is significantly shorter than the 5.5 mm estimated by Yankovsky and Bernotiene. We found no other major incongruences between the original description and the new images, but note that details of the legs were inadequately captured and could not be evaluated.

Comments: The holotype of lithuanica was originally assigned to the genus Ectemnia based on its ‘very large’ body size and absence of pedisulcus ( Yankovsky & Bernotiene, 2005). However, as indicated above, Yankovsky and Bernotiene markedly overestimated both wing and body length, undermining their main criterion for assigning lithuanica to Ectemnia . In fact, lithuanica is significantly smaller than any other giant simuliid considered in this study, as can be seen in Fig. 1 View Figure 1 , wherein lithuanica ( Fig. 1H View Figure 1 ) is shown to scale relative to the other inclusions ( Fig. 1A–G View Figure 1 ). The other feature mentioned by Yankovsky and Bernotiene (i.e.

DESCRIPTION OF SIX NEW INCLUSIONS OF GIANT BALTIC AMBER BLACK FLIES