SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd8dea20c9353798b68ba651d914f3d0a1ffc950cf5c13400ede2b298495212a5' 
  AND token = 'JaDHM4QIvJUKk9ihtPOOcW+6a8NwQn76iDZBQHwrBHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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