SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88ddb2431e99a095b31c98dd5cba5b4097e0afd9cb84f88189de0445bc292ae2' 
  AND token = 'NKcP8QZda3FB92UXctq94O0LGk4PaMhPRQX1CgqSBCI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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