SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '065539f73accfe368305eeb38021291211e7a28a0dc9df9166db0d972db5d387' 
  AND token = 's8Tn4CPM/OIFzNnFk+xeLLhn7K3Xmqn1D42D/8C4Iew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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