SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fbe0f5f5e72aa4272fe3ba6d8ac38173f1dbeae2faca09ae80b13eb849cb5682' 
  AND token = '4OTxQk49dzIJ0I2eHWEAXI7bsfB9JBlLTvyfFnE+M6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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