SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84d86f5f9235ac832bedffe1d2ac1d58b5d405bcfe8983b448935964dc2dfdc0' 
  AND token = 'T6GsOR4WvvhgdnbBvLq+4tNcMe8AU+CfwWCdNZ91H5I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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