SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bffdbeabe59f0a847fb954ba07e2b5696e723049dbf01c5a47b25c26fa179850' 
  AND token = '7RJvOxWbRh95/2EP9lwowgTghrQeLwQViDqBK5nuYz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}