SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cd7b3b5f93afbc4585235c8a477634426b7354c043c0559d8b415fa08b3fa92' 
  AND token = 'IRJ8sqzFZkyIz7pVJRvScVvIqqiwETA1ImVZJZUmrC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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