SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4958638f30822938773b437a191027a91ddac33253e9ecbb11149d294ace13fe' 
  AND token = 'NBbsAVpzsPf3CwvMKHY/zJuNbzLNRUhwAAl+oHSRqKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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