SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25aae6af33576f412014df5cba9c75ed6a8c74d305cd79bf7f39d27567e3dc2e' 
  AND token = '+u1zEk1vK5Cn94GBtdo0mUlkCLwvplFKFJqYKWCCzfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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