Thorax porcellana
In 3 days ~10% in a week ~30%
Thorax porcellana Saussure is a species of epilamprid cockroach occurring in Sri Lanka and India. Both sexes are fully winged, but only the male takes flight, and then rarely and on short flights. Louis M. Roth speculated in 1981 that the arched tegmina found in Phoraspis and Thorax were similar to that of Phlebonotus pallens and would suggest similar maternal care. The Indian entomologist S. Bhoopathy confirmed in 1998 that this ovoviviparous species carries some 30-40 hatchling nymphs for their first two instars in a special recess under the domed forewings on the dorsum of the mother. During their stay of about 7 weeks they drink a pinkish liquid secreted from between the tergites of their mother’s abdomen. They also use their relatively long, sharp, mandibular tooth-like processes to pierce the mother’s cuticle and feed directly on her haemolymph. These 'teeth' are lost after two instars when there is no longer a close association with the mother.
"Immediately after hatching, the first instar nymphs crawled over the abdomen of the mother. The upper surface of her abdomen became markedly depressed into a fairly tight spacious trough or chamber with its sides raised. As the nymphs crawled over her body, she raised up her tegmina, which were large, tough, and dome-shaped, and all the nymphs were accommodated compactly; the tegmina were placed in position so as to conceal all the nymphs and to afford perfect protection.".
Parental care among cockroaches, where offspring are fed on bodily secretions, is not rare, and has been recorded in Perisphaerus, Trichoblatta, Pseudophoraspis, Phlebonotus, Gromphadorhina, Solganea, Cryptocercus and Blattella, whereas biparental care is found only in wood-eating cockroaches - wood is low in nutrients and is made assimilable by micro-organisms in the adult gut. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Bengaluru | 🇮🇳 India |
Rare
Under 5% of wildlife watchers report a Thorax porcellana sighting in Bengaluru on a given day, based on 8 verified sightings from GBIF citizen-science data. It is the 329th most-seen of the 477 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 30%, if each day is a fresh chance.
June and July
In those months about 10% of wildlife watchers report a Thorax porcellana in Bengaluru on a given day, against under 5% in August to May, the lowest months.
Only Bengaluru, in our data
Bengaluru is the only city on Wallace's Line with enough records to rate Thorax porcellana sightings: under 5% of wildlife watchers there report one on a given day.
GBIF citizen-science records
It is estimated from how often the Thorax porcellana is recorded against all the insects logged in Bengaluru (8 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
