SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d0f7c5e15aebffcb448ba5c6589c66b51eaa32d60ad212eb97470970bfb81c9' 
  AND token = '/lHACJI/ISwx4dJIsRDfYNhN8eZwmSvt0l/jgMm+XsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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