SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cf81968eed492e2b861d124f7acef90eb8159cf3f42a1aa8313de790688bd13' 
  AND token = 'edSewj+Ae5bfb3calAwdvPFShysquuU7cQNwKBT8NWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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