SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d7de2035baa7379d81597c09b26f44c9e72cac265102874ca69e3b8de3e5a23' 
  AND token = 'trfvGfdCKXfidCAZwYcTeJQP2daBWzJS21HJLkGeRAk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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