SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '143e9a4954902444eb674e459a710e5f9bf4bab26b61870e50d7ac4f64431515' 
  AND token = 'zIne+uTVUh1jnjTXhd9OUzVIRcJuL/Lfj30N6Lmv1mM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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