SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '89ee6fa9d345de73a32e8c5ba973448623b133826cde834fc83c655b2ef61889' 
  AND token = '2HhO5k8LzsZ4K1Q7nvooi15129V00ZVZA8nqRH+3W6Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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