SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0ff30c83bc25ea8df261783fc98202788770b29edd10ea116d07535992792b6' 
  AND token = 'TyMosRtoeVvHTgoIB/q87RsrqjqSifniyjlsggh5pbU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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