SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '195ea0cb702e471a0976b5000773eeb7dec588c4863231c9b5b5623bb0ef3cfc' 
  AND token = 'kvxxy7RONzOnEHGfuRF4U0Vs3/dSCQIFKDqtVznTOmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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