SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '04f1ceccf127d6e0597f329a53c2f5caf0da6f6e212ba20c87d8705456cc7205' 
  AND token = '+6RRvvj/ON4lVt/YzL9vPpvOxg2KRY8Np6mijZsVijo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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