SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ce70abeaf4407f130a24a6d805dcd1b69840ec8a3f9a6620d389d36eecb22f8' 
  AND token = 'Tbte/lv8cE0AcQi1QozNEFISPxulvffcZUH0ggVfnwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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