SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e90c6c83f8b7f219421ec26118083d8df1e4f395e57b5a8fd88b01a676a54ae5' 
  AND token = '0cJ7Od9vdr3YEp/5vrQ8AnCvGaJ6auWgMYTTqbGe+so=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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