SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23941ab5987e53c2fa09d41570fb46e539a5caeed773e6bda451810a1ce3efaa' 
  AND token = '4dxWOiNsFSJBCCNdPYN8QuXPFGQW/6kQxlQKz+wzirs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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