SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2c04ecbfb5f877357ff76b1de2d11416302d5cde2d2e2e961ced9a4a1c3c4c0e' 
  AND token = 'TzgB8rVaN4an+fC1hJsCUqK19fP7j78PNRjQXY7GVw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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