SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff8da3e96c1141482f8a0bffea783f350753196732607f3133a30acb0cb9364c' 
  AND token = 'HzGSoO5Tl6wvoNJGpOS+T9lpqV1OPLM6KvpjpXPnMu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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