SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a4a5afed4e82058117eb5295690e179d2182a7dc3d952e24ae54dbd901d0161' 
  AND token = 'cewseBIqrOnTXsngBmxg4oUvQUaJ6axKPCpEOjbuRU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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