SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1885793a0f083762967ee3fb2175960a481650fc395268349d72f47a41ba55df' 
  AND token = 'QCLgqf3HJjpr+Drw6TxTq6aQI/jVRyyN8QlK4YuRGMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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