SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8908d05701701b5cdd4b1a48316d32607a3ed236d7b9f2fc513461bf6fece1ca' 
  AND token = 'pPCGtPCsvPoTcAsU8dETcnqYJfz53Omex4rdatYPiPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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