SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7df26fe21eddf32501fd19a775655c0301a4a50eb63c5646c40d0f86a469838' 
  AND token = '4I4JyMPRVLQq3HXxrIZFLYrD1U/OvnvKzsYt26rSUpE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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