SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eda683a677ad7466ee3a796321fa7aca392b50fefad85b21abe5d6551aeaabed' 
  AND token = 'aENxk3m81WFQw9EFnpv0R3HtsjGi+I38vIiJO7CTTTU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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