SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3036d1774e6afac64ee5b96d01824a1e51f964041328ed8f273812bd208fc27' 
  AND token = 'cEe9OONMPzXCt7buOvb6YcUG6zC5Ctc2NGwUHVPYqHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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