SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '692626277d567b095843b418d2325ee9398819b088f3651b131abe77bd38c786' 
  AND token = 'sXbtNf9BpVKkMdg2X/HIKxa04KhH9qFmYPeBEUi5U54=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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