SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5dceeeeac201a8967d957752f684543b9c120fcd52c74113435050c09730082' 
  AND token = 'YaKcDE0m8wbpH8vCc5KxvJivhB8Yt1KEesMOelDbluo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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