SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de1b7e8b3635833eff174a3a10bdb840525ad404183e94ad17d858dfa20255fc' 
  AND token = 'skOSqBuifayW+D46wgM9i+1B5d79MsEW74GLunKrpzU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}