SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58674717b109064e5a71bddabbed4cef61a6b07f9c58b46520641822606ac753' 
  AND token = 'K3XKCnyo+Z2KOCbBiB/NiVlZlsJVUvbjDahBQhKND40=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}