SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aee2005c2dd7b4278440c1f223d456bd2e9266c8544f8c12549387a49a270298' 
  AND token = 'dH1hKrApw8o1qWY3dricuxvP/Xo4TU0Ssf9gKQa3ji8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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