SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccb1a58c1350f72c430db0a8701af09321ba7dbc0974dd2c7c4418b98ef64841' 
  AND token = 'lLGcxytosDDyfbSqEOAiNOTizb4V/HD+OukvxdYM6Ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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