SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1740e0a80710a21d0eb00c8c3be5c4a03d95eb8e9e0a40b29d7944e5d8b5f113' 
  AND token = 'weDCRddPq3NLTTYWjagbR2RDafHXAls/+OruyMmjp6k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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