SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f07245aa8beb861f875968730a2eac28d519064a098e1c4caa2efc7bdf95044d' 
  AND token = 'MyoifQ32GlZ5JWkIjeNp0+OrCgqj9Wj4UJOAypbfZhw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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