SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf65a50d2568874b751cf20b4c3cb12040f6a41380df3fbeec6e0783fb9f2d7b' 
  AND token = 'zD2NkYv2Lk/4GsHvY9hASjCLwxpxWg6pmq4PPTsQ4uw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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