SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41432ed428aa1012a1351a3f625ac6ebbb77a92eff8ae7598d590579f18910e9' 
  AND token = 'lFb4t/YlS+flFzlhcJBbZjQP7VubCnFOA+iC5JizhP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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