SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4705ac060df615b413227b9b3f88ac430c6349d6a5ccab714fdd1335f55a5538' 
  AND token = 'dh74IGKrLxlWUVeZjYM18vCeOkDR7J/7attYEtR5bGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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