SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd066f7c70a650e4d593ddbbefcf3858b9a9055f42c8a57f2f37418293dfa9172' 
  AND token = 'w/Rf5sbDAagz8WAvpmVhVFl1A1aKHjZw5A8XobChRUQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}