Anchiale maculata (Olivier, 1792)

Anchiale maculata (Olivier, 1792) View in CoL

( Fig. 3-5, 15 K-L)

Material examined

- 1 ♀: Indonesien: Molukken, Prov. Maluku Utara, Morotai Id., VIII.2011 [coll. FH, No. 0828–7] ;

- 22 ♂, 18 ♀, 1 ♀ (penultimate instar), 4 eggs: Indonesia, Morotai Island, North Maluku Regency, Daeo Majiko village , XI.-XII.2012 [coll. FH, No's 0828–26 to 67 & E5] ;

- 1 ♂, eggs: ex Zucht: F. Hennemann 2020, F2-Gen., Herkunft: Morotai Id., Daeo village [coll. FH, No. 0828–68 & E6];

- 10 ♀, Indonesia, Morotai Island, North Maluku Regency, Daeo Majiko village , XI.-XII.2012 [coll. IMQC] .

Comments. – A discussion of the intraspecific variability of the different island populations of this widely distributed species along with illustrations of specimens from various islands was presented by Hennemann et al. (2015). The numerous citations of this species may be looked up in Otte & Brock (2005: 45) or online at the Phasmida Species File (http://phasmida.speciesfile.org). Due to the wide geographic distributiona, it is not surprising, that a considerable range of morphological and chromatic variability can be observed in A. maculata with several variations consistently unique to certain localities or islands. Consequently, Hennemann et al. (2015: 21) suggested A. maculata as delimited currently to represent a superspecies that is in the process of allopatric speciation, a hypothesis which however needs scrutiny by a molecular approach i. e. DNA-barcoding of the numerous island populations from throughout the geography of Wallacea.

While previously few specimens from the island of Morotai were known, a large series of specimens is now available and allows a survey of the morphological variability of this island population. Comparison to populations from other islands of the same ecoregion that is formed by the northern Maluku islands, i. e. Halmahera, Bacan or Obi was conducted and did not reveal any consistent, significant morphological differences or trends. The only character that is more or less pronounced in ♀ of the Morotai population and not observed in specimens from any other localities are the posteromedian swellings of abdominal terga VII-IX ( Fig. 5 A-B). Regarding size, the series at hand comprises almost the entire known size range of A. maculata (see measurements given below). While ♂ are very constant in colour, ♀ vary from dark green with a brownish wash over various shades of ochre and brown to dark brown. Greenish specimens appear to be more commonly encountered than in other island populations and have so far only been recorded from the islands of Halmahera and Bacan (Hennemann, et al., 2015: 22). A few specimens have most of the dorsal surface of the mesonotum and abdominal terga as well as the tegmina and costal region of the alae contrasting white ( Fig. 4B) and occasionally only a faint whitish posteromedian marking is observed on the tegmina. The almost black anal fan stated to be distinct for Morotai ♀ by Hennemann et al. (2015: 22) is rather an individual trait of the concerned specimen, as can be seen by the series now available. Actually, the colour of the anal fan varies and the greater number of specimens has it with distinct transparent mottling and rather average for A. maculata . As for other populations (see Hennemann et al., 2015: 23, Fig. 25-30) the eggs of the Morotai population differ notably from those originating from other islands. From the known eggs of A. maculata populations they are most similar to those from Halmahera and Bacan, which however is not surprising due to the geographical vicinity. They however differ from both by the larger capitulum and more prominently rugulose and verrucose central lateral portions of the capsule ( Fig. 16 K-L).

Body lengths (excluding cerci): ♀ 165.0-194.0 mm, ♂ 110.0-122.0 mm. Length of alae of ♀ 63.0-76.0 mm.

Culture stock of A. maculata has been introduced to Europe from the islands of Halmahera and Bacan in 2012 but both stocks were lost after only a few generations. Stock from Morotai has been imported by M. Ortiz ( France) in 2020 is now being successfully reared in captivity and breeding is not particularly difficult in large well-ventilated cages with fairly high humidity achieved by a daily spray of water. Bramble ( Rubus spp. , Rosaceae ), oak ( Quercus robur , Fagaceae ) and salal ( Gaultheria shallon , Ericaceae ) are well-accepted as alternative food plants. Males are very active and capable of active flight over considerable distances and both sexes frequently flash their wings when disturbed with ♂ often walking around with their wings held open for several minutes after the disturbance. Females produce an average of 4- 5 eggs per day per ♀, which are flicked away singularly by an abrupt movement of the abdomen. Incubation takes some 4-5 months if stored in moist conditions and at temperatures of 22-26°. At the same temperatures ♂ reach maturity after about 4-5 months while ♀ usually take a month longer.

Eggs ( Fig. 16 K-L). – A description of the eggs of the Morotai population appears helpful for future delimitation of the diverse egg morphology of the various island populations.

Capsule 1.2x longer than high and 1.5-1.6x longer than wide, compressed laterally, elliptical in cross-section, approximately lens-shaped and surrounded by a prominent dorso-ventral keel. Capsule surface minutely but densely granulose. Lateral surfaces with two shallow impressions anteriorly and the central portion are convex and prominently rugulose and verrucose. From the lateral aspect the dorsal and ventral surfaces have a rounded indention just below the dorsal margin. Polar area protruded into an irregular and obtusely verrucose swelling and with a distinct indention anteriorly near micropylar cup and posteriorly. Micropylar plate long, slender, roughly parallel-sided and running along entire dorsal surface of egg, posterior end reaching to polar area, weakly widened and with a small micropylar cup. Surface of micropylar plate strongly bulgy and irregularly verrucose. Anterior margin of capsule somewhat swollen. Operculum ovoid to weakly rhomboidal, flat but with the outer margin slightly raised and minutely pitted. Capitulum large, knob-like with four prominent lateral impressions; distinctly stalked. General colouration rather plain dark greyish to orangey brown, the A. ♀ dorsal view [FH, No. 0828-34]. B. ♀ dorsal view [FH, No. 0828-29]. C. ♂ dorsolateral view [FH, No. 0828-63]. D. Live captive reared ♂. impressed portions somewhat darker in colour than raised parts. Capitulum greyish buff.

Measurements [mm]:

- Length (including capitulum) 4.7- 4.9,

- Length 4.5 -4.6,

- Width 3.0- 3.1,

- Height 4.3-4.4,

- Length of micropylar plate 4.6 -4.7.

Distribution. – The distributional range of A. maculata comprises almost the whole of Wallacea, from Peleng in the west and Morotai in the north towards the Kei Islands in the southeast. A detailed summary of known records was provided by Hennemann et al. (2015: 25).