SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b2d730a66f9d2949371e07e2be29586a84fdb4a8b2dc448579969ec21d25ceaf' 
  AND token = 'Ll6v81tpeUsEGtWQJt8LxMTvtxvdQaK7+OEN17GnvIk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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