SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0dae1e02432239b37a93d77cdf7e42ac4e56ebd7007050b25be3cff872eec74' 
  AND token = 'AptjjxWfQ9eIkfa32kL95lfBOODxMYLpenybuTFP0KA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00068

JSON explain

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