SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d4938da3ba81ae46381255838984b24f8d4b6d003b130bb4dabdf6ff88ad6d0' 
  AND token = 'wD4CVFIt7w+jPnajNDOngUPDd4J/sndmmOZE7W+PmdI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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