SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '672f7c01d278d7d4f87473e5913f1642c7c19145085e765616de8f674d35cb8d' 
  AND token = 'MWQuRK//EOJ1pcpRYo2I/MeZ9usZ425ohwIHCZe9sQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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