SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b20496f772132bff161fb7b0e685082f12d9011a71a290f3caa7e5c78a465833' 
  AND token = 'l+hFQafO9hsJrRyqA6mNzaLfjC5DlYc3JqRjmc7XPmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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