SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d62321eb8a4259eab2f14803a32ebe3e8beb61616a641972aebe541f9a20dfc' 
  AND token = 'w/n2Ll5RKzzsthgt5hzyEnO5yLFPZ1kbf+vr17eiaIM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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