SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d486d06ec0a9be75d281b5b5ff7b07cd87a949db8f35d50ce7bb1e10df6d361' 
  AND token = 'qzoktjaw52lcvl7u2zXquMzqcHs4g6P8DFM8dxOKqWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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