SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b0bff98fa22b819080a7f60860ea3fd288c059ff5e652b6c38f356f5dcafad4d' 
  AND token = 'YMhwcRyew2OMLOreuXbyWhet6erngPldtABNzdZ1WD0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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