SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '753f95f8496fa61bc564b9910b5eace94d70154f5f5c105ba228d4d26986de3e' 
  AND token = 'IWouGbkypGTyVLILTNcbO8PCpBxcebSAxYMi9g1uSfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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