SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afaf062c2988704963ec1d79c5211fbbc91353301517103686564b6234b32317' 
  AND token = 'hJwu6vUlpiAur0WFtBSXLJiZHqIQcRVbwVga9qr09z8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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