SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43f61fa95072c59c8b70d06195683c326154b9a66219c1c097ddce2d7c505043' 
  AND token = 'mXzsayG1Uk3SzwsY9coB0ZEW6jR7Yt4ZvHoQwYOXERU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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