SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '83a0ae5c8b1fcda8a367a4c46dea33f45eb9e72f443313b87f0960fd563a9b65' 
  AND token = 'NDnnzt/G81SHmaBe/Kq1bqzQvd62hjW07thwo+U5xNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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