SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea6bb037d3606bb8ecccf30072ece8d461637f7b5fc99c22fd937356eb51951a' 
  AND token = 'YOQApRF1JmdrSNLRcPuoTanvsr9yOKzYveAUcmqYmVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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