SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c7711ec63b06e7fd6e29b6ee26273001def776944f46dfcde1660f6df25b3a6' 
  AND token = 'vOiim0Kl9S4wmLG1BglJED0QKeOerWNyq+uBdOVFJsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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