SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '629e96f88cb39cc3870bf379318245cb91fc22dbd8f591b8d5a10e5369029c8b' 
  AND token = 'C86zZmuXLQzq7VB9lEx7DtAwUruHXVkQvJC8ddmrUsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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