SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2eb52e9e8825a1a2ba15f7ff79c4de234ea58e456c0666299560f563493491fe' 
  AND token = 'kjpOEC2DDHHAEenLSLMA+7qE5jrQHKhY3YWa5bbCD/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00069

JSON explain

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