SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd901f1eaaf2296931a7b502478cec61716cd5695636a8490122126e7c4401642' 
  AND token = 'acVVIU5ZUmNJS9l7FyUv8lezDAScdFhMKd+Gvj6ZG4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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