SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9c30836ee688438f1fafe8369784dd1e49b968704893fc3812b22fa94acae081' 
  AND token = '9exuW9Awh7fMgFQyDDgBunhyZBupDaqGLQt6fNg3Dy8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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