SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5a619f10607c4d35f2d17ceffa21b6e87d272527f5049500b1fef12614cf1ac' 
  AND token = 'aCXXUcUQrhYitEct4fD3EsE1D3nGp0U1cA1EPCkP9Fc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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