SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c0a6df2389f6e0b0cae3d88e6303cdf30e69e0936daab44bc55013cb170f03b8' 
  AND token = '6sDXBLByjb5AW46B/t6cOhFQ+9ctmnrgEOEvAM9ZD4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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