Architectonica modesta
- Usual depth33–77 m
- Water temperature26–29 °C
- Best monthsMarch, May, and July
- How commonRare
Photo credit: (c) Cheryl Stinchcomb, some rights reserved (CC BY) · CC BY · iNaturalist
About this species
Architectonica modesta, the giant sundial, is a species of sea snail, a marine gastropod mollusk in the family Architectonicidae, which are known as the staircase shells or sundials.
Text from the Wikipedia article “Architectonica modesta”, licensed CC BY-SA 4.0. Read the article
Where and when
Where it has been recorded
Worldwide
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Best months
Worldwide (open data)
- January: 2 records
- February: 3 records
- March: 8 records
- April: 6 records
- May: 9 records
- June: 6 records
- July: 10 records
- August: 6 records
- September: 2 records
- October: 0 records
- November: 1 records
- December: 2 records
Depth and water temperature
Depth
Mostly recorded at 33–77 m · Deepest record: 77 m
Water temperature
Recorded in surface water of 26–29 °C
Photos
(c) portioid, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) portioid, some rights reserved (CC BY) · CC BY · iNaturalist
Names and classification
Names in 1 more languages
- Japanese
- シロスジグルマ
Other scientific names: Solarium modestum
Similar species
Giant sundialArchitectonica maxima
Clear sundialArchitectonica perspectiva
- Variegated sundial
Heliacus variegatus
Sources and credits
Names and taxonomy: WoRMS (CC BY 4.0) and the GBIF Backbone (CC BY 4.0). Photos: iNaturalist observers, each under the licence shown (CC0, CC BY or CC BY-SA).
- Depth, temperature, months and maps: records from OBIS and GBIF under CC0 or CC BY.
- Descriptions: Wikipedia, licensed CC BY-SA, each linked to its article.
- Conservation status as published by GBIF (IUCN Red List).
- 26 open-data records from 1908 to 2006.
- Species data updated October 26, 2026.
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