SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd99a32a676ca6c97931a2ee1bd27f08d19549243599ec7a9cdecb401a645b69' 
  AND token = 'nsRKMZe27vmSxueCZXZwL7C46YlzO8uG476g7wah1WE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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