SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1aa406cc6a22010819f976614f0de8dfd34dd685d298ec326d8d4fc484bc68c2' 
  AND token = 'L1TB+v6QyREJL5jLuHAe7SohR/LPkKg6aru51Pv/Bk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00073

JSON explain

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