SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0adb149654a619b8b6780c6a7195342b327e9d32454b53cf94107c8af455b045' 
  AND token = 'CtOMz6yYXVJKjYikbnLEnr8qaEGeBfaNEVwigfrwLj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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