SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '598836e19c153dc4792822c92d2db155c5f65ec2dcf50fdfe0a6bfbbb901ac90' 
  AND token = 'fmuN9w61Hx/L00SXvK6qa/6xPnarWgyyrdQ9A7x0FRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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