SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52db96a725b00a84308d54f571cc6b0ac6774dc68183e78e248d390e21ba4bfe' 
  AND token = 'pJycmaj93vOYEz0fCEdqlXQImvopBXxZt/wjTKIiM/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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