SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1b9b5efc11330276eec47badb78ca4544f4e2a7c17f12963933f1a17483b258' 
  AND token = 'bMTDl5+s5SEI+NZU7OMH1JQBbFym69OBZcS8pvKpKVE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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