SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f4e6e00fef935e6559339f66d58eebd0aecb8a7cc2d93eed7f840a2d0093eda4' 
  AND token = 'ckROOwfRKCensQpqPOz0cZZ/ZlDd8bM8dhY29/BD+ZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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