Choroterpes (Dilatognathus) major ( Ulmer 1939 )

Kluge, Nikita J., 2014, Indonesian species of Dilatognathus Kluge 2012 (Ephemeroptera, Leptophlebiidae, Choroterpes s. l.) and species-specific sexual dimorphism in development of maxilla, Zootaxa 3786 (1) : -

Choroterpes (Dilatognathus) major ( Ulmer 1939)

( Figs 27 , 33 )

= Choroterpides major Ulmer 1939

= Dilatognathus/g(1) sp.1: Kluge 2012

Material. INDONESIA, JAVA, Cibodas (= Tjibodas), pool under waterfall at southern side of golf field, 6– 11.VIII. 2009, coll. N. Kluge & L. Sheyko: 25 larvae: 2 L/S♂, 1 L n♂, 6 L n♀, 2 L n- 1♂, 5 L n-1♀, 2 L n-2♀, 3 L n-3♀, 4 L n- 4 ♀.

Additional descriptions. Larva. Described by Ulmer (1939). CUTICULAR COLORATION: Cuticle of head, pronotum and mesonotum brown, with diffusive markings; cuticle of legs and abdomen light brownish, nearly unicolorous, without contrasting markings.

HYPODERMAL COLORATION: General color dark blackish-brown. Head and thorax with dark maculae; labrum and exposed areas of mandibles dark brown; palps and other mouth parts ocher. Each leg with coxa, trochanter, femur and tibia dark brown; tarsus and extreme apex of tibia ocher ( Fig. 33 ). Abdominal terga nearly entirely dark brown, with pair of small submedian blanks adjacent to anterior margin; abdominal sterna ocher with brown, variable. Tergalii dark brown; dorsal lamella darker, with main trachea of the same color and side tracheae nearly invisible; ventral lamella lighter, with main trachea of the same color and side tracheae poorly visible.

SHAPE AND SETATION. Maxilla without dentiseta at least beginning from instar L n-4; with maxillary tusk at least beginning from instar L n-4; without ventro-apical flange beginning from instar L n-3. At least female maxilla of penpen-pen-penultimolarva (L n-4) with well-expressed maxillary tusk; ventro-apical flange small (similar to pen-penpenultimolava of Ch. bogori : Fig. 20 ). In next instars (from L n-3 to L n) ventro-apical flange not expressed, and maxillary tusk becomes progressively longer at each instar. Three vestiges of pectinate setae present in all instars. Other characters as in Ch. (D.) cataractae ( Kluge 2012) . In contrast to Ch. (D.) bogori , tergalii II–VII with apical processes small and thread-like ( Fig. 27 ).

Subimago (extracted from mature larva). CUTICULAR COLORATION: Cuticle of thorax at most light with brown sclerites; mesonotum at most brown; most part of medioscutum and submedioscutum brown, posterior scutal protuberance brown (as in Fig. 38 ). Wings brown.

HYPODERMAL COLORATION: General color dark blackish-brown. Femora entirely dark brown; tibiae dark brown with light apex; fore tarsus dark brown with light articulations; middle and hind tarsi light, shaded with brown. Abdominal terga and sterna brown with small paired blanks.

TEXTURE: On each leg 1st tarsomere (shortened and fused with tibia) covered by microtrichiae of the same shape as microtrichiae on tibia; 2nd–5th tarsomeres covered by pointed microlepides.

Imago, male. Described by Ulmer (1939). Not examined.

Imago, female. Unknown.

Dimension. Length of ultimolarva 7–9 mm.

Distribution. Java; reported also from Sumatra ( Ulmer 1939).

Habitat. All larvae examined by me, were collected in a single place, under waterfall which falls from the forest in national park. We did not find larvae of this species in other places, including neighboring waterfalls in the national park and the botanic garden. The place of larval inhabitance was so small, that we were unable to collect enough specimens to rear imagoes. In this respect Ch. (D.) major markedly differs from Ch. (D.) bogori , whose larvae inhabit polluted rivers.

Figures

FIGURES 19 – 28. Choroterpes (Dilatognathus) spp. 19 – 24, Ch. (D.) bogori: 19 and 20, apex of maxilla in pen-penpenultimate larval instar (ventral view; tusk, ventro-apical flange and vestiges of pectinate ventral setae are shown, other setae not shown): 19, male; 20, female; 21 and 21, genitals of male imago, ventral view (holotype); 23, tergalius III (second existent); 24, middle part of anterior margin of labrum, ventral view. 25 – 26, genitals and enlarged penis of Choroterpides exiguus (Eaton 1884 [Thraulus]) (from Eaton 1884: Pl. 13, Fig. 20 * 2). 27, Choroterpes (Dilatognathus) major, tergalius III (second existent). 28, Choroterpes (Dilatognathus) minor, the same.

FIGURES 29 – 33. Choroterpes (Dilatognathus) spp. 29, Ch. (D.) bogori, abdomen of male imago, spread on slide (holotype); 30, Ch. (D.) cataractae, the same (holotype); 31, Ch. (D.) bogori, hind leg of male imago (holotype); 32, Ch. (D.) cataractae, the same (holotype); 33, Ch. (D.) major, hind leg of mature larva with developing subimaginal leg.

FIGURES 34 – 39. Choroterpes (Dilatognathus) spp. 34 – 37, median part of postrior margin of abdominal tergum of ultimolarva: 34 – 35, Ch. (D.) bogori; 36 – 37, Ch. (D.) cataractae; 34 and 36, tergum II; 35 and 37, tergum VII. 38 – 39, Ch. (D.) bogori: 38, exuviae of right half of subimaginal mesonotum; 39, egg.