SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10bd2c909d580103563caec4cf0af2913fd84624eb126c032d7fc2e945ee29fe' 
  AND token = '1CinrmdzZd+nx8M/23KrQWt52xYpuNmbH4iiQvpdnaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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