Eristalinus megacephalus
In 3 days ~10% in a week ~20%
Eristalinus megacephalus is a species of hoverfly. Eristalinus megacephalus has a black abdomen and golden horizontal stripes larger in males. It has a black thorax, legs with black tips, transparent, flexible wings, a large head and golden compound eyes with pale purple spots. Being about 8–11 mm long, it is a good pollinator, and uses Batesian mimicry to look like hymenopteran bees and scare away predators. Its appearance is also similar to bee flies (family Bombyliidae). The species is listed in 2: 63 of Rossi's publication Mantissa insectorum. There are no subspecies. It is the rarest species of the genus Eristalinus, and is common but not abundant.
The species's flight period is from May to October, and is most plentiful from June to July. E. megacephalus can be found in most countries, including South Africa, Egypt, Sri Lanka, China, Taiwan, India, Java, Guam, Southern Spain, Turkey, North Africa, Iran, and coastal parts of Italy.
Eristalinus quinquelineatus Eristalinus taeniops Eristalinus sepulchralis Eristalinus fuscicornis Eristalinus barclayi Eristalinus seychellarum Eristalinus aeneus Media... Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Camargue | 🇫🇷 France |
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Mumbai | 🇮🇳 India | |
| 2 | Kuala Lumpur | 🇲🇾 Malaysia | |
| 3 | Guangzhou | 🇨🇳 China | |
| 4 | Hong Kong | 🇨🇳 China | |
| 5 | Singapore | 🇸🇬 Singapore |
Rare
Under 5% of wildlife watchers report a Big-Headed Lagoon Fly sighting in Hong Kong on a given day, based on 5 verified sightings from GBIF citizen-science data. It is the 1005th most-seen of the 1125 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
October
In that month about 10% of wildlife watchers report a Big-Headed Lagoon Fly in Hong Kong on a given day, against under 5% in November to September, the lowest months. That is one of Hong Kong's driest months, with about 50 mm of rain against 280 mm in June.
Between 2 and 5 pm
Across all the parks we cover, that three-hour window holds the most Big-Headed Lagoon Fly sightings with a recorded time, and about 9 in 10 of them come between 6 am and 6 pm: it is a daytime animal.
4th of 5
Of the 5 cities where we can rate Big-Headed Lagoon Fly sightings, Hong Kong ranks 4th at under 5%. The best odds are in Mumbai (India, about 10%), Kuala Lumpur (Malaysia, under 5%) and Guangzhou (China, under 5%).
GBIF citizen-science records
It is estimated from how often the Big-Headed Lagoon Fly is recorded against all the insects logged in Hong Kong (5 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.
