Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6bc9e3023d90040b65d74016dd66d63af512206a6ca4ddd1d01bf673b84430cc' 
  AND token = 'bIDmn8f/KxbGX9zDnRKk8bt6f2N37SbE3B9135UXBP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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