SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a444f3d6ce9d6f050cf36126f163433ec69d38c089ebbf50378a2577306be874' 
  AND token = 'sf9+SypSgsrczskF7AaBKcj28vPHgVfNnHHffJpu6Ww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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