SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e5c0be57d5db765fff4fa36d074c39904fc0ee3566f63542650866e7fa91912' 
  AND token = 'V7sQ93wu3wk8ZxGqCnn1GoCXqO0gBE54b559uhlsOp0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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