SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4225c85886d240d669765f67371317dca322ada24ec78cb891861209944bb437' 
  AND token = '5eeKigm2CEbgKFI/zlYv4XlmA+Ef74gtEPLYot8CeYs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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