SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b9c701a055fb6fa511c9e7418ba72209f3ba0022012573989206796a160c2787' 
  AND token = 'vkairYi4mcz6fXiDFNs6JIFWSx/0HRWcYMRQcqO9bPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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