SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ec52eb6fc1b82cd74607f9f1064953491401fc5d23b2c2ef4d44d2c7941aa03' 
  AND token = 'qyrukhIKkQFuiO7HiicSzfsKtgADl6ocs6VKGLWhdIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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