SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '431df62531eb39169ddadabd427e0a1bf676852edfb8b4568501dabd26073996' 
  AND token = 'oKgYsLJiNSljhx6Voc+7R69DGf2BdhBcOhtP44mXW3U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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