SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3a29eaa6c82ac092bdd8956ac6591a52687f63d6ecf7fa7f97e1482603d9065b' 
  AND token = 'W0DSheKCYHNRrHlfEtUPjS16eyuoRexO9gcMbLFwXIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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