SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d07461666c48dbfb528d222225497a4a039fd46f43f8baa2a06d29afa057f31' 
  AND token = 'WeAq8Es944Cx9SuLx/jhPKu/szdT3+LkXtGLXlzWnIc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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