SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5ff355f7f8fe4085a47db8d2c1af41df99d0d3eec8271227f6f47e199ac05933' 
  AND token = 'YCMwInpGKsZcxIun3pgh/HH9nyx5x8tvdQrXJgMrrFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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