SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5eda2c7944a67758d1f1e24db2c10585f2a53a69d9874837a8d712b849e4697e' 
  AND token = '35oOltKG9BEAYmbUYtWC4g/iYTKo/2VDpTLubZ/c50w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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