SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4132abb4a6887bd5b1302d1e35aafa594fa3335c63f52118e9802e72c987f1c2' 
  AND token = 'cges+lPdRe15xu23qXGO02yvkw0bVpsHzZwBjlrW+OM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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