SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c7182d9225ded9901eaf1451e90ec76e99d754c372128bb8baebfc3355c2798' 
  AND token = 'w7yqTOTigz6Q4fy2SGJe8xzyMU3ScMGzRUUfwZLC8/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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