SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afb58c406f36e5899b5ad26cc61221f37e238cfaa8e8dcbe93433c0363db4d69' 
  AND token = 'DC07FWFCLn6AcRFJDCZIfpZnqZI8fvkjpWCEiX8c8ZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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