SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '292ca57c705eb040ba4907b60cc078fdef08860569fdccf581749cd25b5f3ab7' 
  AND token = '8lftnWE3XSsXAJQk6XLN5DVXeOGxEGOGSRNY0EyfTi4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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