SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41cd320fe71eaff1549195d174e2441c0ba4cee4480a5112eefe74c42fb22d94' 
  AND token = 'o+wHZRdXbbffVsNEyQdBDPncPqogmCVbrOA1bAsjLH8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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