SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45bcb646b85be41870053ceeb06c2b250c65fc6645b5079cda0b4fe749e282d4' 
  AND token = 'C6CPBrDqpFycorFxm2QhuJg/WpSlMjR4wffWHo7TCYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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