SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9caa5148e60a62a6545e2d6cef1193b10f3828322561bcbc23ce0363768b2dc0' 
  AND token = 'NuE+j2JEoOL8y//GVdY64iDuGhkUiugHKAY1haN+F0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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