SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3533623b8bd812fac9140b2587cef8a287f20592dba19968e8812043da7020a5' 
  AND token = '9CQ5kmY6aZ7jOTfRodExaSEfVyqhDLoUXH7ccSyLp68=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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