SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0080eb9df2d4f6742b2387aaef9a7496d55ea79994fae2fded56746cabf301af' 
  AND token = 'FNVkJ4LE7rko4QrjNsUrv6esJmQ4bpWzHnPmyMkBr8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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