Electrocambala ornata, Moritz & Wesener, 2021

Moritz, Leif & Wesener, Thomas, 2021, Electrocambalidae fam. nov., a new family of Cambalidea from Cretaceous Burmese amber (Diplopoda, Spirostreptida), European Journal of Taxonomy 755 (1), pp. 22-46 : 26-30

Electrocambala ornata gen. et sp. nov.

urn:lsid:zoobank.org:act:E66F551F-57A6-4FF6-BD95-C06FD4AD3627

Figs 1–2

Diagnosis

Electrocambala ornata gen. et sp. nov. differs from Electrocambala cretacea gen. et sp. nov. by the presence of net-like ornamentation on the ventral half of the prozonite ( Fig. 1F ), V-shaped striae laterally on the collum ( Fig. 1D ) and the absence of longitudinal ridges on the body rings. Metazonite on ventral half with 7 longitudinal striae. Metazonite from body ring 4 onwards distinctly arched ( Fig. 1A ). Body rings 2–5 narrower than collum and following body rings ( Fig. 1B ). Anterior gonopod coxite more than twice as long as wide, with inner lobe longer than outer lobe, telopodite narrow, as long as coxite. Posterior gonopod simple, as long as anterior gonopod, projecting between inner and outer lobes of anterior gonopod ( Fig. 1G–H ).

Etymology

From the Latin word ʻ ornatus ʼ meaning ʻornamentedʼ in reference to the net-like ornamentation and striae on the body rings of the species. Noun in apposition.

Type material

Holotype MYANMAR • ♂; Kachin State, Hukawng Valley, Mid-Cretaceous Burmese amber inclusion; formerly in the collection of Patrick Müller ( BuB1151 ); ZFMK-MYR7369 .

Paratype MYANMAR • 1 ♀; same collection data as for holotype; formerly in the collection of Patrick Müller ( BuB1142 ); ZFMK MYR7370 .

Other material examined

MYANMAR • 1 ♂; same collection data as for holotype; in the collection of Patrick Müller ( BuB1962 ) • 1 ♀; same collection data as for holotype; in the collection of Patrick Müller ( BuB1825 ) .

Description

HABITUS. At least up to 46 +6 (holotype, ZFMK-MYR7369) body rings ( Fig. 1A ) (ZFMK-MYR7370 = 42 +3; BuB1825 = 40 +4; BuB1962 = 45 +4); body cylindrical, slender, up to at least 14.7 mm long, diameter 0.5 mm, males smaller. Colour light to dark brown, posterior margin of metazonites light grey.

HEAD.As wide as collum and body ring 6 onwards, wider than body ring 2–5 ( Fig. 1B–C ). Labrum and front of head with setae ( Fig. 1D ). 32/21 ommatidia (21 probably an artefact) arranged in circular patch. Incisura lateralis present, closed. Antennae reaching to posterior margin of body ring 4, with 7 antennomeres, covered by setae, 6>3>4=5>1> 2>7, with four apical sensory cones. Antennomeres 5 and 6 broader ( Fig. 1D ). Labrum tridentate. Mandible base divided into small cardo and large stipes ( Fig. 1C–D ). Gnathochilarium with eumentum and promentum, stipes along whole length of gnathochilarium, lamella lingualis not completely separated by promentum, not reaching to eumentum.

TRUNK. Collum only slightly curved, projecting over posterior margin of head ( Fig. 1B–D ). Collum with small triangular process projecting ventrally, reaching to height of upper margin of mandibular base, with 2 striae touching anterior forming a V ( Fig. 1D ). Body rings totally fused from body ring 5 onwards. Anterior four body rings with sternites free from pleuro-tergites. Prozonite separated from metazonite by constriction. Metazonite from body ring 6 onwards distinctly arched and wider than prozonite ( Fig. 1C ). Prozonite ventrally with net-like ornamentation ( Fig. 1F ). Metazonite ventrally with up to 7 longitudinal striae ( Fig. 1F ). Posterior margin of metazonites with 2–3 rows of setae ( Fig. 1D ). Ozopores from body ring 6 onwards lateral on metazonite, at middle height of body ring ( Fig. 1B ). Midbody rings (9) ca 0.7 times as long as diameter.

LEGS. First two leg pairs surrounded by first pleuro-tergite (collum), leg pair 3 surrounded by 2 nd pleurotergite close to 3 rd pleuro-tergite, body rings 3 and 4 seemingly legless, from body ring 5 onwards 2 leg pairs per body ring ( Fig. 1B–C ). Midbody legs with coxa, prefemur, femur, postfemur, tibia, tarsus. Tarsus> prefemur = femur> postfemur> tibia> coxa. Podomeres with few setae. Tarsus with tarsal claw and accessory spine ( Fig. 1E ). Leg pairs 1 and 2 without accessory spine. Coxa of 2 nd leg pair inserts medial of coxa of 1 st leg pair.

POSTERIOR BODY RINGS. Preanal ring without epiproct projecting, with 5 longitudinal lateral grooves and setae.Anal valves with at least 10 marginal setae and up to 8 setae on surface. Subanal scale not projecting over anal valve. Posterior 3–6 body rings legless ( Fig. 1A ).

MALE SEXUAL CHARACTERS. Smaller and more slender than females ( Figs 1A , 2A vs Fig. 2B–C ). In male 1 st leg pair present, reduced in size not in segmentation, without tarsal claw. Penis with wide base and curved tip, with short setae ( Fig. 1D ). Anterior (8 th leg) and posterior gonopod (9 th leg) well-developed, on body ring 7 ( Fig. 1B–C ). Anterior gonopod coxite flat with two rounded apical lobes (inner and outer lobe), telopodite as long as inner coxal lobe, inserting at base of coxa, with few setae. Presence of flagellum unknown. Posterior gonopod as long as anterior gonopod, with rounded tip. Apex curved anteriorly, creating an open channel. Anterior surface with possible remnant of seminal groove reaching up to apex ( Fig. 1G–H ).

FEMALE SEXUAL CHARACTERS. Larger and wider than male ( Fig. 2B–C ). First leg pair reduced in length and broadened. Vulva not sufficiently preserved for description.

Remarks

Electrocambala ornata gen. et sp. nov. was discovered in one case (ZFMK MYR7370) in the same amber stone as a specimen of Electrocambala cretacea gen. et sp. nov. described below, showing that both species lived in temporal and geographical sympatry, not unlike recent species of the Cambalopsidae in SE Asia (e.g., Likhitrakarn et al. 2020).

Measurements and taphonomy

ZFMK-MYR7369

AMBER DESCRIPTION.Amber flat, semi-circle, 15.45 × 6.6 × 2.84 mm, polished, yellow, clear transparent.

SYNINCLUSIONS. Soil particles, stellate hairs, plant parts, Acari.

TAPHONOMIC FEATURES. Body curved as in defence ( Fig. 1A ). Defence fluid released from anterior body rings, form transparent dark brown bubbles above ozopores ( Fig. 1B ). Field of ommatidia damaged on left side. Gonopods everted ( Fig. 1B ). Anal-valves open ( Fig. 1A ). Body laterally slightly flattened. Body rings 26–38 damaged on right side and from leg pair 10 onwards right leg missing (artefact from polishing) ( Fig. 1A ).

ZFMK-MYR7370

MEASUREMENTS. 14.5 mm long, 0.5 mm in diameter.

AMBER DESCRIPTION. Amber flat, oval-shaped, 48.3 × 29.5 × 7.4 mm, polished, yellow, reddish transparent.

SYNINCLUSIONS. Soil particles, sporangia of fungi, bark, wood fibre, leaves, Diptera, Coleoptera, Electrocambala cretacea gen. et sp. nov., small brown droplets.

TAPHONOMIC FEATURES. Anterior body coiled as in defence ( Fig. 2C ). Field of ommatidia visible, but single ommatidia not distinguishable. Setation only partially preserved. Legs only partially preserved, mostly decayed ( Fig. 2C ). Vulva visible, but poorly preserved. Surrounded by brownish film.

BuB1825

MEASUREMENTS. 14.7 mm long, 0.5 mm in diameter.

AMBER DESCRIPTION.Amber flat, semi-circle, 18.23 × 9.09 × 4.05 mm, polished, yellow to reddish, clear transparent, with fissures.

SYNINCLUSIONS. Sporangia of fungi, stellate hairs.

TAPHONOMIC FEATURES. Anterior body bent as in defence. Secretion of defence fluid ( Fig. 2B ). Setation not preserved. Legs only partially preserved ( Fig. 2B ). Characters partly obscured by body. Amber with fissure.

BuB1962

MEASUREMENTS. 11.9 mm long, 0.3 mm in diameter.

AMBER DESCRIPTION. Amber cuboid, 12.28 × 5.57 × 3.29 mm, polished, yellow, clear transparent. From larger piece, includes 5 pieces.

SYNINCLUSIONS. Soil particles, sporangia of fungi, stellate hairs, parts of arthropod appendages.

TAPHONOMIC FEATURES. Anterior body bent as in defence ( Fig. 2A ). Head damaged, antennae deformed, legs only partially preserved ( Fig. 2A ), anal valves of preanal ring missing, body rings 9–12 and 21–31 damaged.

Figures

Fig. 1. Electrocambala ornata gen. et sp. nov., holotype, ♂ (ZFMK-MYR7369). A. Habitus, lateral view, photograph. B. Head and anterior body rings, lateral view, photograph. C. Head and anterior body rings, lateral view, volume rendering. D. Head and anterior body rings, lateral view, drawing. E. Tarsus of midbody leg, photograph. F. Midbody ring, photograph. G. Gonopods, frontal view, segmentation. H. Gonopods, lateral view, segmentation. Abbreviations: ag = anterior gonopod; as = accessory spine; at = antennae; cl = claw; co = collum; cx = coxite; L = leg; la = labrum; md = mandible; mz = metazonite; om = ommatidia; pe = penis; pg = posterior gonopod; pz = prozonite; ta = tarsus; te = telopodite.

Fig. 2. Electrocambala ornata gen. et sp. nov., other material, photographs. A. ♂ (BuB1962). B. ♀ (BuB1825). C. Paratype, ♀ (ZFMK MYR7370).