SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f809fe495007ecac752b30b6c64ebbf0a37bf1ca3fc2e2bc7bc5764664ba67d3' 
  AND token = 'OCo9PTU+xhGpB3XvmgWzWE6pIk60M1h9oLOV+dVpQmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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