SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '260ec55668fd6f38cbdfe650b2bdbc954f082f0d786ea6ce98554df2e2717474' 
  AND token = 'tZQvJ1OwigC99xu/QiTrqvdycyMoOcyD/o7ysrPS8Yk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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