SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9aacce32dce40214153009bbc5ded621cae38b39bc066f2a019e0528198f1366' 
  AND token = 'X5mUMhR/DsJeBtgp6tAySMrQ7R8Kgj1roVRNdFS4duk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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