SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70c4e5ed9f22cbcb94c80a85b8fdfe36b22774213940ecd049869dd52d61c5a7' 
  AND token = '2OC7rH8PHgTpzKtfDypq5A15P6AaTJP/AeWjyYzfqSw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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