SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db072c798dcbcd7d3bb52086db7dad12352473395b18e0cbc4d2822a3201dd67' 
  AND token = 'qvUQQlrnZOHrrDrHkT+IfXn/uyom+mYLpZpqEINktWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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