SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '437022443c2694075f1123c4801285c816dfc229f7612d7a054eecc39eddc2e6' 
  AND token = '0ggNvmvgmidmb3BqbahHJxmU5+XnAUHFax2RAAcIIFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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