SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0673fc438d8c650c636623fd51ca03d0cd1e880334a7cc6a5be7197c6c1a7cbc' 
  AND token = 'KHBZMw8+GS7/zkBx+JU0OnY8JbishAksgGOqATQ63mQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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