SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ed5f7db373d6257f70b90659bf37b819986ecebe3d18a6b5488879bf655482f' 
  AND token = 'UFcwWNFrHtlU01JzOxrCrk0ksjJ2wLPbAYlQKujnGik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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