SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '312025e813e48768d32a13a91cb79dc6f72f837f66f573340641d49672ab19da' 
  AND token = 'qVEVe3t+2wgyFvJjkkl4ajvoedVJHSrC5OcB0MrTPFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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