SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96dd5bc9af9280ed00f32979833a8ceb035758b15a4df1ad5ffae021403cac5a' 
  AND token = 'WMkxb57UgrPgKFhS8RIBGWJJrB8EorItw8m4uA4gG08=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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