SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e3a9b314a271368c2c30735db794ae2db04fa860f6badfa71776ee885d58f312' 
  AND token = 'hhQqTpZymSsvb2My/I/0cc7Yx5iJ0aHCI3sf9N6j+7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}