SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa0acb477a280585ec34db37d86b9206ca875ca5f56d4f8bf04b36f72d4daf59' 
  AND token = 'Ut/40/6hYLmiCGnl8RdWieb26nzvc0Sz4WdCuUUNwzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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