SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '385943febda3bfc3c01b9fb8aa226ca30d51ff9444c235299b61d43809c41279' 
  AND token = '9hJARcFwEj+EIgvALFANFva1QnKoG65x/kEJwulQYjI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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