SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eabdc47d99e293c663b49c20b5950d269e65bf44da3eab5ab3392245182a05eb' 
  AND token = 'GuVJADciMyvb+faYMQZXKgyQ8dGA0chPPGTuDAQdEnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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