SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2becbbd44b341e5a232339ec0e52de3c0964bfe40e6e7260555b5966e9b5d2b0' 
  AND token = 'gYTTUQnED+6LiEmAcHJM7kx8FLbfuYdt8BjigCfwZpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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