SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2e6381520b3a5ec96afd1b300fe86f6261e8f609383cdf29cc9d523cc00c755c' 
  AND token = 'fXnVKTb/yDzDAUzufZnpCUc3PIg5KVZHLYT0Bm/gI7A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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