SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a30c419b5913490b0989c7fff8815bedd229f7c9f8cf7fefc6dda49d42e74b9c' 
  AND token = 'V7Zz5yOEUsSZzKx83ST4stiC4i7wDV2dYFUiQKROArc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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