SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '262828eded63efc75aae4514335ecbbc8c5270a6017e7bb479b55a943d8eb7d5' 
  AND token = 'q74njZyCx7fHlQkH8xm8eE7l0nX3M5MvVeVNnUh3DYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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