SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a855ba7d33f9884f0e66d1b2167881a9bcc9ad0edc3d223b4840159b7db667ac' 
  AND token = 'c9nm6q4YYfee90pSDBbmCUrXmAkfuwHD+zAyV1ChqTU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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