SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ff738295cfbb466d1c279bcb2bff4247d3e40e92575bae2738da16d0aec942e' 
  AND token = 'uCcYEu4pYaak9FkpN6nYiFRucCQoKdyrOT6c9/6de0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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