SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9681f7de068f4e3686403897059d00e3c0aba14d993e5b9116268d2665f35779' 
  AND token = 'o/xeG5kuuVhe6oTQQ6KE5vy71KKWqCuwejVF226Sjhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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