SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7bcbd1ee0ab482ef3eed2db8cef1dfcc3415349b71ab94e81a154fb4918855ee' 
  AND token = 'OPscS5IvnRzkEfT5oxvnAC92tx4p9Wci1hkIzNJqEJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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