SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0d28658955f808119a9e007a0255fbf6a1b9666090e3b162e3bd3db9230d7056' 
  AND token = 'YbBelmsR3lSDlcmfFktTfWUJtVLL8hYG2sXGd58ZlGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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