SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58d02fb14d7fb9be6665a2c856f02e3f63717fa6753ee79506afa9c24d8bdc84' 
  AND token = 'vynjNlyB1Igy6rS4i6FhGq8QK757DXIUJ1kc+Zllj8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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