SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcaeb70f0c8d4b2bab894bcfa2f972cafd231bdaf5c21c621f49c69f5219f066' 
  AND token = 'f1bs2lCQ/kvrPDVoYLcvajG9r08CWJaBP9CM3WrLcdA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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