SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3bc44c01dee75dce3a7454978ae950daff25faad8444b2ed20046f999a8476dc' 
  AND token = 'i21swfsV+eAe3WFbZgByI1gauMW8vD16URG/9eTjEPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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