SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e2696533dec837edeadc37f93957b86d877ff22f608040a87108c46a0bb20f7' 
  AND token = '9tUcncOBEg4L1gtcEtPoR8SjgYMwFiWGkDEo+i2E9Fg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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