SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59c64d39a2e5afc3471af2ae082c251553666db04373c3b0757c815385c7eeaa' 
  AND token = 'vfd+pkAytFazLQyG4ICmMm+qYKqn7inZjKoKmVbMsdw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00183

JSON explain

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