SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1be0d1a67df53cef9d5eae2aec43902adf9aadeed3a3509ea92f813e9f8b9f05' 
  AND token = 'XwhNtoGjf5GIPOjCeKSANOpsPGy9L4vnfaismmpnjvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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