SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e390faabfadfaa45956625da517a64e8689cb56bfe4120b631707537fc12c7b' 
  AND token = '3jhClG2b0hfyCcoWzMzMWHzSeFssFulOVHg+9SghvHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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