SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e11efe15f96d8b1a80304852963993f7f299a6b16becdbd80299deff6d86425' 
  AND token = 'qT1mYmEIbS5+SfWaagx1qmYO6qozYPVQD5yBCQu4GNA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00103

JSON explain

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