SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0bdc3aee5c23cfe707bda0698ab6796b56b4e3fd5998de332879db8a9f4e267c' 
  AND token = 'pcQhDnHaP+o748prp5vFU1bowkrI6WBj/jD7na/PKrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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