SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3312176b097597890762208ec16ee161c881f9885d8cb1167502d3bbc82deff4' 
  AND token = 'QdpGAgXznp5vHjvN1K13awQa95Q+JS72DLpFJYZd9qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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