SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '82e3413219109d916acf708c639faa312b039b25125d2ebfb57dcdd3a63a4025' 
  AND token = 'PvCVnsHLVkXYVjuromjBAlKIcedcmJseVWN91OSbrz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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